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/*
* Copyright (C) 2006 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.widget;
import android.annotation.ColorInt;
import android.annotation.DrawableRes;
import android.annotation.NonNull;
import android.annotation.TestApi;
import android.compat.annotation.UnsupportedAppUsage;
import android.content.Context;
import android.content.Intent;
import android.content.res.Configuration;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.TransitionDrawable;
import android.os.Build;
import android.os.Bundle;
import android.os.Debug;
import android.os.Handler;
import android.os.Parcel;
import android.os.Parcelable;
import android.os.StrictMode;
import android.os.Trace;
import android.text.Editable;
import android.text.InputType;
import android.text.TextUtils;
import android.text.TextWatcher;
import android.util.AttributeSet;
import android.util.Log;
import android.util.LongSparseArray;
import android.util.SparseArray;
import android.util.SparseBooleanArray;
import android.util.StateSet;
import android.view.ActionMode;
import android.view.ContextMenu.ContextMenuInfo;
import android.view.Gravity;
import android.view.HapticFeedbackConstants;
import android.view.InputDevice;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.PointerIcon;
import android.view.VelocityTracker;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewDebug;
import android.view.ViewGroup;
import android.view.ViewHierarchyEncoder;
import android.view.ViewParent;
import android.view.ViewTreeObserver;
import android.view.accessibility.AccessibilityEvent;
import android.view.accessibility.AccessibilityManager;
import android.view.accessibility.AccessibilityNodeInfo;
import android.view.accessibility.AccessibilityNodeInfo.AccessibilityAction;
import android.view.accessibility.AccessibilityNodeInfo.CollectionInfo;
import android.view.animation.Interpolator;
import android.view.animation.LinearInterpolator;
import android.view.inputmethod.BaseInputConnection;
import android.view.inputmethod.CompletionInfo;
import android.view.inputmethod.CorrectionInfo;
import android.view.inputmethod.EditorInfo;
import android.view.inputmethod.ExtractedText;
import android.view.inputmethod.ExtractedTextRequest;
import android.view.inputmethod.InputConnection;
import android.view.inputmethod.InputContentInfo;
import android.view.inputmethod.InputMethodManager;
import android.view.inputmethod.SurroundingText;
import android.view.inspector.InspectableProperty;
import android.view.inspector.InspectableProperty.EnumEntry;
import android.widget.RemoteViews.InteractionHandler;
import com.android.internal.R;
import com.android.internal.annotations.VisibleForTesting;
import java.util.ArrayList;
import java.util.List;
/**
* Base class that can be used to implement virtualized lists of items. A list does
* not have a spatial definition here. For instance, subclasses of this class can
* display the content of the list in a grid, in a carousel, as stack, etc.
*
* @attr ref android.R.styleable#AbsListView_listSelector
* @attr ref android.R.styleable#AbsListView_drawSelectorOnTop
* @attr ref android.R.styleable#AbsListView_stackFromBottom
* @attr ref android.R.styleable#AbsListView_scrollingCache
* @attr ref android.R.styleable#AbsListView_textFilterEnabled
* @attr ref android.R.styleable#AbsListView_transcriptMode
* @attr ref android.R.styleable#AbsListView_cacheColorHint
* @attr ref android.R.styleable#AbsListView_fastScrollEnabled
* @attr ref android.R.styleable#AbsListView_smoothScrollbar
* @attr ref android.R.styleable#AbsListView_choiceMode
*/
public abstract class AbsListView extends AdapterView implements TextWatcher,
ViewTreeObserver.OnGlobalLayoutListener, Filter.FilterListener,
ViewTreeObserver.OnTouchModeChangeListener,
RemoteViewsAdapter.RemoteAdapterConnectionCallback {
@SuppressWarnings("UnusedDeclaration")
private static final String TAG = "AbsListView";
/**
* Disables the transcript mode.
*
* @see #setTranscriptMode(int)
*/
public static final int TRANSCRIPT_MODE_DISABLED = 0;
/**
* The list will automatically scroll to the bottom when a data set change
* notification is received and only if the last item is already visible
* on screen.
*
* @see #setTranscriptMode(int)
*/
public static final int TRANSCRIPT_MODE_NORMAL = 1;
/**
* The list will automatically scroll to the bottom, no matter what items
* are currently visible.
*
* @see #setTranscriptMode(int)
*/
public static final int TRANSCRIPT_MODE_ALWAYS_SCROLL = 2;
/**
* Indicates that we are not in the middle of a touch gesture
*/
static final int TOUCH_MODE_REST = -1;
/**
* Indicates we just received the touch event and we are waiting to see if the it is a tap or a
* scroll gesture.
*/
static final int TOUCH_MODE_DOWN = 0;
/**
* Indicates the touch has been recognized as a tap and we are now waiting to see if the touch
* is a longpress
*/
static final int TOUCH_MODE_TAP = 1;
/**
* Indicates we have waited for everything we can wait for, but the user's finger is still down
*/
static final int TOUCH_MODE_DONE_WAITING = 2;
/**
* Indicates the touch gesture is a scroll
*/
static final int TOUCH_MODE_SCROLL = 3;
/**
* Indicates the view is in the process of being flung
*/
static final int TOUCH_MODE_FLING = 4;
/**
* Indicates the touch gesture is an overscroll - a scroll beyond the beginning or end.
*/
static final int TOUCH_MODE_OVERSCROLL = 5;
/**
* Indicates the view is being flung outside of normal content bounds
* and will spring back.
*/
static final int TOUCH_MODE_OVERFLING = 6;
/**
* Regular layout - usually an unsolicited layout from the view system
*/
static final int LAYOUT_NORMAL = 0;
/**
* Show the first item
*/
static final int LAYOUT_FORCE_TOP = 1;
/**
* Force the selected item to be on somewhere on the screen
*/
static final int LAYOUT_SET_SELECTION = 2;
/**
* Show the last item
*/
static final int LAYOUT_FORCE_BOTTOM = 3;
/**
* Make a mSelectedItem appear in a specific location and build the rest of
* the views from there. The top is specified by mSpecificTop.
*/
static final int LAYOUT_SPECIFIC = 4;
/**
* Layout to sync as a result of a data change. Restore mSyncPosition to have its top
* at mSpecificTop
*/
static final int LAYOUT_SYNC = 5;
/**
* Layout as a result of using the navigation keys
*/
static final int LAYOUT_MOVE_SELECTION = 6;
/**
* Normal list that does not indicate choices
*/
public static final int CHOICE_MODE_NONE = 0;
/**
* The list allows up to one choice
*/
public static final int CHOICE_MODE_SINGLE = 1;
/**
* The list allows multiple choices
*/
public static final int CHOICE_MODE_MULTIPLE = 2;
/**
* The list allows multiple choices in a modal selection mode
*/
public static final int CHOICE_MODE_MULTIPLE_MODAL = 3;
/**
* The thread that created this view.
*/
private final Thread mOwnerThread;
/**
* Controls if/how the user may choose/check items in the list
*/
int mChoiceMode = CHOICE_MODE_NONE;
/**
* Controls CHOICE_MODE_MULTIPLE_MODAL. null when inactive.
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
ActionMode mChoiceActionMode;
/**
* Wrapper for the multiple choice mode callback; AbsListView needs to perform
* a few extra actions around what application code does.
*/
MultiChoiceModeWrapper mMultiChoiceModeCallback;
/**
* Running count of how many items are currently checked
*/
int mCheckedItemCount;
/**
* Running state of which positions are currently checked
*/
SparseBooleanArray mCheckStates;
/**
* Running state of which IDs are currently checked.
* If there is a value for a given key, the checked state for that ID is true
* and the value holds the last known position in the adapter for that id.
*/
LongSparseArray mCheckedIdStates;
/**
* Controls how the next layout will happen
*/
@UnsupportedAppUsage
int mLayoutMode = LAYOUT_NORMAL;
/**
* Should be used by subclasses to listen to changes in the dataset
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
AdapterDataSetObserver mDataSetObserver;
/**
* The adapter containing the data to be displayed by this view
*/
@UnsupportedAppUsage
ListAdapter mAdapter;
/**
* The remote adapter containing the data to be displayed by this view to be set
*/
private RemoteViewsAdapter mRemoteAdapter;
/**
* If mAdapter != null, whenever this is true the adapter has stable IDs.
*/
boolean mAdapterHasStableIds;
/**
* This flag indicates the a full notify is required when the RemoteViewsAdapter connects
*/
private boolean mDeferNotifyDataSetChanged = false;
/**
* Indicates whether the list selector should be drawn on top of the children or behind
*/
boolean mDrawSelectorOnTop = false;
/**
* The drawable used to draw the selector
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023)
Drawable mSelector;
/**
* The current position of the selector in the list.
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P)
int mSelectorPosition = INVALID_POSITION;
/**
* Defines the selector's location and dimension at drawing time
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P)
Rect mSelectorRect = new Rect();
/**
* The data set used to store unused views that should be reused during the next layout
* to avoid creating new ones
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 123769398)
final RecycleBin mRecycler = new RecycleBin();
/**
* The selection's left padding
*/
int mSelectionLeftPadding = 0;
/**
* The selection's top padding
*/
@UnsupportedAppUsage
int mSelectionTopPadding = 0;
/**
* The selection's right padding
*/
int mSelectionRightPadding = 0;
/**
* The selection's bottom padding
*/
@UnsupportedAppUsage
int mSelectionBottomPadding = 0;
/**
* This view's padding
*/
Rect mListPadding = new Rect();
/**
* Subclasses must retain their measure spec from onMeasure() into this member
*/
int mWidthMeasureSpec = 0;
/**
* The top scroll indicator
*/
View mScrollUp;
/**
* The down scroll indicator
*/
View mScrollDown;
/**
* When the view is scrolling, this flag is set to true to indicate subclasses that
* the drawing cache was enabled on the children
*/
boolean mCachingStarted;
boolean mCachingActive;
/**
* The position of the view that received the down motion event
*/
@UnsupportedAppUsage
int mMotionPosition;
/**
* The offset to the top of the mMotionPosition view when the down motion event was received
*/
int mMotionViewOriginalTop;
/**
* The desired offset to the top of the mMotionPosition view after a scroll
*/
int mMotionViewNewTop;
/**
* The X value associated with the the down motion event
*/
int mMotionX;
/**
* The Y value associated with the the down motion event
*/
@UnsupportedAppUsage
int mMotionY;
/**
* One of TOUCH_MODE_REST, TOUCH_MODE_DOWN, TOUCH_MODE_TAP, TOUCH_MODE_SCROLL, or
* TOUCH_MODE_DONE_WAITING
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 123769413)
int mTouchMode = TOUCH_MODE_REST;
/**
* Y value from on the previous motion event (if any)
*/
int mLastY;
/**
* How far the finger moved before we started scrolling
*/
int mMotionCorrection;
/**
* Determines speed during touch scrolling
*/
@UnsupportedAppUsage
private VelocityTracker mVelocityTracker;
/**
* Handles one frame of a fling
*
* To interrupt a fling early you should use smoothScrollBy(0,0) instead
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P)
private FlingRunnable mFlingRunnable;
/**
* Handles scrolling between positions within the list.
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
AbsPositionScroller mPositionScroller;
/**
* The offset in pixels form the top of the AdapterView to the top
* of the currently selected view. Used to save and restore state.
*/
int mSelectedTop = 0;
/**
* Indicates whether the list is stacked from the bottom edge or
* the top edge.
*/
boolean mStackFromBottom;
/**
* When set to true, the list automatically discards the children's
* bitmap cache after scrolling.
*/
boolean mScrollingCacheEnabled;
/**
* Whether or not to enable the fast scroll feature on this list
*/
boolean mFastScrollEnabled;
/**
* Whether or not to always show the fast scroll feature on this list
*/
boolean mFastScrollAlwaysVisible;
/**
* Optional callback to notify client when scroll position has changed
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 123769353)
private OnScrollListener mOnScrollListener;
/**
* Keeps track of our accessory window
*/
@UnsupportedAppUsage
PopupWindow mPopup;
/**
* Used with type filter window
*/
EditText mTextFilter;
/**
* Indicates whether to use pixels-based or position-based scrollbar
* properties.
*/
private boolean mSmoothScrollbarEnabled = true;
/**
* Indicates that this view supports filtering
*/
private boolean mTextFilterEnabled;
/**
* Indicates that this view is currently displaying a filtered view of the data
*/
private boolean mFiltered;
/**
* Rectangle used for hit testing children
*/
private Rect mTouchFrame;
/**
* The position to resurrect the selected position to.
*/
int mResurrectToPosition = INVALID_POSITION;
@UnsupportedAppUsage
private ContextMenuInfo mContextMenuInfo = null;
/**
* Maximum distance to record overscroll
*/
int mOverscrollMax;
/**
* Content height divided by this is the overscroll limit.
*/
static final int OVERSCROLL_LIMIT_DIVISOR = 3;
/**
* How many positions in either direction we will search to try to
* find a checked item with a stable ID that moved position across
* a data set change. If the item isn't found it will be unselected.
*/
private static final int CHECK_POSITION_SEARCH_DISTANCE = 20;
/**
* Used to request a layout when we changed touch mode
*/
private static final int TOUCH_MODE_UNKNOWN = -1;
private static final int TOUCH_MODE_ON = 0;
private static final int TOUCH_MODE_OFF = 1;
private int mLastTouchMode = TOUCH_MODE_UNKNOWN;
private static final boolean PROFILE_SCROLLING = false;
private boolean mScrollProfilingStarted = false;
private static final boolean PROFILE_FLINGING = false;
private boolean mFlingProfilingStarted = false;
/**
* The StrictMode "critical time span" objects to catch animation
* stutters. Non-null when a time-sensitive animation is
* in-flight. Must call finish() on them when done animating.
* These are no-ops on user builds.
*/
private StrictMode.Span mScrollStrictSpan = null;
private StrictMode.Span mFlingStrictSpan = null;
/**
* The last CheckForLongPress runnable we posted, if any
*/
@UnsupportedAppUsage
private CheckForLongPress mPendingCheckForLongPress;
/**
* The last CheckForTap runnable we posted, if any
*/
@UnsupportedAppUsage
private CheckForTap mPendingCheckForTap;
/**
* The last CheckForKeyLongPress runnable we posted, if any
*/
private CheckForKeyLongPress mPendingCheckForKeyLongPress;
/**
* Acts upon click
*/
private AbsListView.PerformClick mPerformClick;
/**
* Delayed action for touch mode.
*/
private Runnable mTouchModeReset;
/**
* Whether the most recent touch event stream resulted in a successful
* long-press action. This is reset on TOUCH_DOWN.
*/
private boolean mHasPerformedLongPress;
/**
* This view is in transcript mode -- it shows the bottom of the list when the data
* changes
*/
private int mTranscriptMode;
/**
* Indicates that this list is always drawn on top of a solid, single-color, opaque
* background
*/
private int mCacheColorHint;
/**
* The select child's view (from the adapter's getView) is enabled.
*/
@UnsupportedAppUsage
private boolean mIsChildViewEnabled;
/**
* The cached drawable state for the selector. Accounts for child enabled
* state, but otherwise identical to the view's own drawable state.
*/
private int[] mSelectorState;
/**
* The last scroll state reported to clients through {@link OnScrollListener}.
*/
private int mLastScrollState = OnScrollListener.SCROLL_STATE_IDLE;
/**
* Helper object that renders and controls the fast scroll thumb.
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 123768941)
private FastScroller mFastScroll;
/**
* Temporary holder for fast scroller style until a FastScroller object
* is created.
*/
private int mFastScrollStyle;
private boolean mGlobalLayoutListenerAddedFilter;
@UnsupportedAppUsage
private int mTouchSlop;
private float mDensityScale;
private float mVerticalScrollFactor;
private InputConnection mDefInputConnection;
private InputConnectionWrapper mPublicInputConnection;
private Runnable mClearScrollingCache;
Runnable mPositionScrollAfterLayout;
private int mMinimumVelocity;
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 124051740)
private int mMaximumVelocity;
private float mVelocityScale = 1.0f;
final boolean[] mIsScrap = new boolean[1];
private final int[] mScrollOffset = new int[2];
private final int[] mScrollConsumed = new int[2];
private final float[] mTmpPoint = new float[2];
// Used for offsetting MotionEvents that we feed to the VelocityTracker.
// In the future it would be nice to be able to give this to the VelocityTracker
// directly, or alternatively put a VT into absolute-positioning mode that only
// reads the raw screen-coordinate x/y values.
private int mNestedYOffset = 0;
// True when the popup should be hidden because of a call to
// dispatchDisplayHint()
private boolean mPopupHidden;
/**
* ID of the active pointer. This is used to retain consistency during
* drags/flings if multiple pointers are used.
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023)
private int mActivePointerId = INVALID_POINTER;
/**
* Sentinel value for no current active pointer.
* Used by {@link #mActivePointerId}.
*/
private static final int INVALID_POINTER = -1;
/**
* Maximum distance to overscroll by during edge effects
*/
@UnsupportedAppUsage
int mOverscrollDistance;
/**
* Maximum distance to overfling during edge effects
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 123769379)
int mOverflingDistance;
// These two EdgeGlows are always set and used together.
// Checking one for null is as good as checking both.
/**
* Tracks the state of the top edge glow.
*
* Even though this field is practically final, we cannot make it final because there are apps
* setting it via reflection and they need to keep working until they target Q.
* @hide
*/
@NonNull
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 123769408)
@VisibleForTesting
public EdgeEffect mEdgeGlowTop;
/**
* Tracks the state of the bottom edge glow.
*
* Even though this field is practically final, we cannot make it final because there are apps
* setting it via reflection and they need to keep working until they target Q.
* @hide
*/
@NonNull
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 123768444)
@VisibleForTesting
public EdgeEffect mEdgeGlowBottom;
/**
* An estimate of how many pixels are between the top of the list and
* the top of the first position in the adapter, based on the last time
* we saw it. Used to hint where to draw edge glows.
*/
private int mFirstPositionDistanceGuess;
/**
* An estimate of how many pixels are between the bottom of the list and
* the bottom of the last position in the adapter, based on the last time
* we saw it. Used to hint where to draw edge glows.
*/
private int mLastPositionDistanceGuess;
/**
* Used for determining when to cancel out of overscroll.
*/
private int mDirection = 0;
/**
* Tracked on measurement in transcript mode. Makes sure that we can still pin to
* the bottom correctly on resizes.
*/
private boolean mForceTranscriptScroll;
/**
* Used for interacting with list items from an accessibility service.
*/
private ListItemAccessibilityDelegate mAccessibilityDelegate;
/**
* Track the item count from the last time we handled a data change.
*/
private int mLastHandledItemCount;
/**
* Used for smooth scrolling at a consistent rate
*/
static final Interpolator sLinearInterpolator = new LinearInterpolator();
/**
* The saved state that we will be restoring from when we next sync.
* Kept here so that if we happen to be asked to save our state before
* the sync happens, we can return this existing data rather than losing
* it.
*/
private SavedState mPendingSync;
/**
* Whether the view is in the process of detaching from its window.
*/
private boolean mIsDetaching;
/**
* Interface definition for a callback to be invoked when the list or grid
* has been scrolled.
*/
public interface OnScrollListener {
/**
* The view is not scrolling. Note navigating the list using the trackball counts as
* being in the idle state since these transitions are not animated.
*/
public static int SCROLL_STATE_IDLE = 0;
/**
* The user is scrolling using touch, and their finger is still on the screen
*/
public static int SCROLL_STATE_TOUCH_SCROLL = 1;
/**
* The user had previously been scrolling using touch and had performed a fling. The
* animation is now coasting to a stop
*/
public static int SCROLL_STATE_FLING = 2;
/**
* Callback method to be invoked while the list view or grid view is being scrolled. If the
* view is being scrolled, this method will be called before the next frame of the scroll is
* rendered. In particular, it will be called before any calls to
* {@link Adapter#getView(int, View, ViewGroup)}.
*
* @param view The view whose scroll state is being reported
*
* @param scrollState The current scroll state. One of
* {@link #SCROLL_STATE_TOUCH_SCROLL} or {@link #SCROLL_STATE_IDLE}.
*/
public void onScrollStateChanged(AbsListView view, int scrollState);
/**
* Callback method to be invoked when the list or grid has been scrolled. This will be
* called after the scroll has completed
* @param view The view whose scroll state is being reported
* @param firstVisibleItem the index of the first visible cell (ignore if
* visibleItemCount == 0)
* @param visibleItemCount the number of visible cells
* @param totalItemCount the number of items in the list adapter
*/
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount,
int totalItemCount);
}
/**
* The top-level view of a list item can implement this interface to allow
* itself to modify the bounds of the selection shown for that item.
*/
public interface SelectionBoundsAdjuster {
/**
* Called to allow the list item to adjust the bounds shown for
* its selection.
*
* @param bounds On call, this contains the bounds the list has
* selected for the item (that is the bounds of the entire view). The
* values can be modified as desired.
*/
public void adjustListItemSelectionBounds(Rect bounds);
}
public AbsListView(Context context) {
super(context);
mEdgeGlowBottom = new EdgeEffect(context);
mEdgeGlowTop = new EdgeEffect(context);
initAbsListView();
mOwnerThread = Thread.currentThread();
setVerticalScrollBarEnabled(true);
TypedArray a = context.obtainStyledAttributes(R.styleable.View);
initializeScrollbarsInternal(a);
a.recycle();
}
public AbsListView(Context context, AttributeSet attrs) {
this(context, attrs, com.android.internal.R.attr.absListViewStyle);
}
public AbsListView(Context context, AttributeSet attrs, int defStyleAttr) {
this(context, attrs, defStyleAttr, 0);
}
public AbsListView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
mEdgeGlowBottom = new EdgeEffect(context, attrs);
mEdgeGlowTop = new EdgeEffect(context, attrs);
initAbsListView();
mOwnerThread = Thread.currentThread();
final TypedArray a = context.obtainStyledAttributes(
attrs, R.styleable.AbsListView, defStyleAttr, defStyleRes);
saveAttributeDataForStyleable(context, R.styleable.AbsListView, attrs, a, defStyleAttr,
defStyleRes);
final Drawable selector = a.getDrawable(R.styleable.AbsListView_listSelector);
if (selector != null) {
setSelector(selector);
}
mDrawSelectorOnTop = a.getBoolean(R.styleable.AbsListView_drawSelectorOnTop, false);
setStackFromBottom(a.getBoolean(
R.styleable.AbsListView_stackFromBottom, false));
setScrollingCacheEnabled(a.getBoolean(
R.styleable.AbsListView_scrollingCache, true));
setTextFilterEnabled(a.getBoolean(
R.styleable.AbsListView_textFilterEnabled, false));
setTranscriptMode(a.getInt(
R.styleable.AbsListView_transcriptMode, TRANSCRIPT_MODE_DISABLED));
setCacheColorHint(a.getColor(
R.styleable.AbsListView_cacheColorHint, 0));
setSmoothScrollbarEnabled(a.getBoolean(
R.styleable.AbsListView_smoothScrollbar, true));
setChoiceMode(a.getInt(
R.styleable.AbsListView_choiceMode, CHOICE_MODE_NONE));
setFastScrollEnabled(a.getBoolean(
R.styleable.AbsListView_fastScrollEnabled, false));
setFastScrollStyle(a.getResourceId(
R.styleable.AbsListView_fastScrollStyle, 0));
setFastScrollAlwaysVisible(a.getBoolean(
R.styleable.AbsListView_fastScrollAlwaysVisible, false));
a.recycle();
if (context.getResources().getConfiguration().uiMode == Configuration.UI_MODE_TYPE_WATCH) {
setRevealOnFocusHint(false);
}
}
private void initAbsListView() {
// Setting focusable in touch mode will set the focusable property to true
setClickable(true);
setFocusableInTouchMode(true);
setWillNotDraw(false);
setAlwaysDrawnWithCacheEnabled(false);
setScrollingCacheEnabled(true);
final ViewConfiguration configuration = ViewConfiguration.get(mContext);
mTouchSlop = configuration.getScaledTouchSlop();
mVerticalScrollFactor = configuration.getScaledVerticalScrollFactor();
mMinimumVelocity = configuration.getScaledMinimumFlingVelocity();
mMaximumVelocity = configuration.getScaledMaximumFlingVelocity();
mOverscrollDistance = configuration.getScaledOverscrollDistance();
mOverflingDistance = configuration.getScaledOverflingDistance();
mDensityScale = getContext().getResources().getDisplayMetrics().density;
}
/**
* {@inheritDoc}
*/
@Override
public void setAdapter(ListAdapter adapter) {
if (adapter != null) {
mAdapterHasStableIds = mAdapter.hasStableIds();
if (mChoiceMode != CHOICE_MODE_NONE && mAdapterHasStableIds &&
mCheckedIdStates == null) {
mCheckedIdStates = new LongSparseArray();
}
}
clearChoices();
}
/**
* Returns the number of items currently selected. This will only be valid
* if the choice mode is not {@link #CHOICE_MODE_NONE} (default).
*
* To determine the specific items that are currently selected, use one of
* the getChecked*
methods.
*
* @return The number of items currently selected
*
* @see #getCheckedItemPosition()
* @see #getCheckedItemPositions()
* @see #getCheckedItemIds()
*/
public int getCheckedItemCount() {
return mCheckedItemCount;
}
/**
* Returns the checked state of the specified position. The result is only
* valid if the choice mode has been set to {@link #CHOICE_MODE_SINGLE}
* or {@link #CHOICE_MODE_MULTIPLE}.
*
* @param position The item whose checked state to return
* @return The item's checked state or false
if choice mode
* is invalid
*
* @see #setChoiceMode(int)
*/
public boolean isItemChecked(int position) {
if (mChoiceMode != CHOICE_MODE_NONE && mCheckStates != null) {
return mCheckStates.get(position);
}
return false;
}
/**
* Returns the currently checked item. The result is only valid if the choice
* mode has been set to {@link #CHOICE_MODE_SINGLE}.
*
* @return The position of the currently checked item or
* {@link #INVALID_POSITION} if nothing is selected
*
* @see #setChoiceMode(int)
*/
public int getCheckedItemPosition() {
if (mChoiceMode == CHOICE_MODE_SINGLE && mCheckStates != null && mCheckStates.size() == 1) {
return mCheckStates.keyAt(0);
}
return INVALID_POSITION;
}
/**
* Returns the set of checked items in the list. The result is only valid if
* the choice mode has not been set to {@link #CHOICE_MODE_NONE}.
*
* @return A SparseBooleanArray which will return true for each call to
* get(int position) where position is a checked position in the
* list and false otherwise, or null
if the choice
* mode is set to {@link #CHOICE_MODE_NONE}.
*/
public SparseBooleanArray getCheckedItemPositions() {
if (mChoiceMode != CHOICE_MODE_NONE) {
return mCheckStates;
}
return null;
}
/**
* Returns the set of checked items ids. The result is only valid if the
* choice mode has not been set to {@link #CHOICE_MODE_NONE} and the adapter
* has stable IDs. ({@link ListAdapter#hasStableIds()} == {@code true})
*
* @return A new array which contains the id of each checked item in the
* list.
*/
public long[] getCheckedItemIds() {
if (mChoiceMode == CHOICE_MODE_NONE || mCheckedIdStates == null || mAdapter == null) {
return new long[0];
}
final LongSparseArray idStates = mCheckedIdStates;
final int count = idStates.size();
final long[] ids = new long[count];
for (int i = 0; i < count; i++) {
ids[i] = idStates.keyAt(i);
}
return ids;
}
/**
* Clear any choices previously set
*/
public void clearChoices() {
if (mCheckStates != null) {
mCheckStates.clear();
}
if (mCheckedIdStates != null) {
mCheckedIdStates.clear();
}
mCheckedItemCount = 0;
}
/**
* Sets the checked state of the specified position. The is only valid if
* the choice mode has been set to {@link #CHOICE_MODE_SINGLE} or
* {@link #CHOICE_MODE_MULTIPLE}.
*
* @param position The item whose checked state is to be checked
* @param value The new checked state for the item
*/
public void setItemChecked(int position, boolean value) {
if (mChoiceMode == CHOICE_MODE_NONE) {
return;
}
// Start selection mode if needed. We don't need to if we're unchecking something.
if (value && mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode == null) {
if (mMultiChoiceModeCallback == null ||
!mMultiChoiceModeCallback.hasWrappedCallback()) {
throw new IllegalStateException("AbsListView: attempted to start selection mode " +
"for CHOICE_MODE_MULTIPLE_MODAL but no choice mode callback was " +
"supplied. Call setMultiChoiceModeListener to set a callback.");
}
mChoiceActionMode = startActionMode(mMultiChoiceModeCallback);
}
final boolean itemCheckChanged;
if (mChoiceMode == CHOICE_MODE_MULTIPLE || mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL) {
boolean oldValue = mCheckStates.get(position);
mCheckStates.put(position, value);
if (mCheckedIdStates != null && mAdapter.hasStableIds()) {
if (value) {
mCheckedIdStates.put(mAdapter.getItemId(position), position);
} else {
mCheckedIdStates.delete(mAdapter.getItemId(position));
}
}
itemCheckChanged = oldValue != value;
if (itemCheckChanged) {
if (value) {
mCheckedItemCount++;
} else {
mCheckedItemCount--;
}
}
if (mChoiceActionMode != null) {
final long id = mAdapter.getItemId(position);
mMultiChoiceModeCallback.onItemCheckedStateChanged(mChoiceActionMode,
position, id, value);
}
} else {
boolean updateIds = mCheckedIdStates != null && mAdapter.hasStableIds();
// Clear all values if we're checking something, or unchecking the currently
// selected item
itemCheckChanged = isItemChecked(position) != value;
if (value || isItemChecked(position)) {
mCheckStates.clear();
if (updateIds) {
mCheckedIdStates.clear();
}
}
// this may end up selecting the value we just cleared but this way
// we ensure length of mCheckStates is 1, a fact getCheckedItemPosition relies on
if (value) {
mCheckStates.put(position, true);
if (updateIds) {
mCheckedIdStates.put(mAdapter.getItemId(position), position);
}
mCheckedItemCount = 1;
} else if (mCheckStates.size() == 0 || !mCheckStates.valueAt(0)) {
mCheckedItemCount = 0;
}
}
// Do not generate a data change while we are in the layout phase or data has not changed
if (!mInLayout && !mBlockLayoutRequests && itemCheckChanged) {
mDataChanged = true;
rememberSyncState();
requestLayout();
}
}
@Override
public boolean performItemClick(View view, int position, long id) {
boolean handled = false;
boolean dispatchItemClick = true;
if (mChoiceMode != CHOICE_MODE_NONE) {
handled = true;
boolean checkedStateChanged = false;
if (mChoiceMode == CHOICE_MODE_MULTIPLE ||
(mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode != null)) {
boolean checked = !mCheckStates.get(position, false);
mCheckStates.put(position, checked);
if (mCheckedIdStates != null && mAdapter.hasStableIds()) {
if (checked) {
mCheckedIdStates.put(mAdapter.getItemId(position), position);
} else {
mCheckedIdStates.delete(mAdapter.getItemId(position));
}
}
if (checked) {
mCheckedItemCount++;
} else {
mCheckedItemCount--;
}
if (mChoiceActionMode != null) {
mMultiChoiceModeCallback.onItemCheckedStateChanged(mChoiceActionMode,
position, id, checked);
dispatchItemClick = false;
}
checkedStateChanged = true;
} else if (mChoiceMode == CHOICE_MODE_SINGLE) {
boolean checked = !mCheckStates.get(position, false);
if (checked) {
mCheckStates.clear();
mCheckStates.put(position, true);
if (mCheckedIdStates != null && mAdapter.hasStableIds()) {
mCheckedIdStates.clear();
mCheckedIdStates.put(mAdapter.getItemId(position), position);
}
mCheckedItemCount = 1;
} else if (mCheckStates.size() == 0 || !mCheckStates.valueAt(0)) {
mCheckedItemCount = 0;
}
checkedStateChanged = true;
}
if (checkedStateChanged) {
updateOnScreenCheckedViews();
}
}
if (dispatchItemClick) {
handled |= super.performItemClick(view, position, id);
}
return handled;
}
/**
* Perform a quick, in-place update of the checked or activated state
* on all visible item views. This should only be called when a valid
* choice mode is active.
*/
private void updateOnScreenCheckedViews() {
final int firstPos = mFirstPosition;
final int count = getChildCount();
final boolean useActivated = getContext().getApplicationInfo().targetSdkVersion
>= android.os.Build.VERSION_CODES.HONEYCOMB;
for (int i = 0; i < count; i++) {
final View child = getChildAt(i);
final int position = firstPos + i;
if (child instanceof Checkable) {
((Checkable) child).setChecked(mCheckStates.get(position));
} else if (useActivated) {
child.setActivated(mCheckStates.get(position));
}
}
}
/**
* @see #setChoiceMode(int)
*
* @return The current choice mode
*/
@InspectableProperty(enumMapping = {
@EnumEntry(value = CHOICE_MODE_NONE, name = "none"),
@EnumEntry(value = CHOICE_MODE_SINGLE, name = "singleChoice"),
@InspectableProperty.EnumEntry(value = CHOICE_MODE_MULTIPLE, name = "multipleChoice"),
@EnumEntry(value = CHOICE_MODE_MULTIPLE_MODAL, name = "multipleChoiceModal")
})
public int getChoiceMode() {
return mChoiceMode;
}
/**
* Defines the choice behavior for the List. By default, Lists do not have any choice behavior
* ({@link #CHOICE_MODE_NONE}). By setting the choiceMode to {@link #CHOICE_MODE_SINGLE}, the
* List allows up to one item to be in a chosen state. By setting the choiceMode to
* {@link #CHOICE_MODE_MULTIPLE}, the list allows any number of items to be chosen.
*
* @param choiceMode One of {@link #CHOICE_MODE_NONE}, {@link #CHOICE_MODE_SINGLE}, or
* {@link #CHOICE_MODE_MULTIPLE}
*/
public void setChoiceMode(int choiceMode) {
mChoiceMode = choiceMode;
if (mChoiceActionMode != null) {
mChoiceActionMode.finish();
mChoiceActionMode = null;
}
if (mChoiceMode != CHOICE_MODE_NONE) {
if (mCheckStates == null) {
mCheckStates = new SparseBooleanArray(0);
}
if (mCheckedIdStates == null && mAdapter != null && mAdapter.hasStableIds()) {
mCheckedIdStates = new LongSparseArray(0);
}
// Modal multi-choice mode only has choices when the mode is active. Clear them.
if (mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL) {
clearChoices();
setLongClickable(true);
}
}
}
/**
* Set a {@link MultiChoiceModeListener} that will manage the lifecycle of the
* selection {@link ActionMode}. Only used when the choice mode is set to
* {@link #CHOICE_MODE_MULTIPLE_MODAL}.
*
* @param listener Listener that will manage the selection mode
*
* @see #setChoiceMode(int)
*/
public void setMultiChoiceModeListener(MultiChoiceModeListener listener) {
if (mMultiChoiceModeCallback == null) {
mMultiChoiceModeCallback = new MultiChoiceModeWrapper();
}
mMultiChoiceModeCallback.setWrapped(listener);
}
/**
* @return true if all list content currently fits within the view boundaries
*/
private boolean contentFits() {
final int childCount = getChildCount();
if (childCount == 0) return true;
if (childCount != mItemCount) return false;
return getChildAt(0).getTop() >= mListPadding.top &&
getChildAt(childCount - 1).getBottom() <= getHeight() - mListPadding.bottom;
}
/**
* Specifies whether fast scrolling is enabled or disabled.
*
* When fast scrolling is enabled, the user can quickly scroll through lists
* by dragging the fast scroll thumb.
*
* If the adapter backing this list implements {@link SectionIndexer}, the
* fast scroller will display section header previews as the user scrolls.
* Additionally, the user will be able to quickly jump between sections by
* tapping along the length of the scroll bar.
*
* @see SectionIndexer
* @see #isFastScrollEnabled()
* @param enabled true to enable fast scrolling, false otherwise
*/
public void setFastScrollEnabled(final boolean enabled) {
if (mFastScrollEnabled != enabled) {
mFastScrollEnabled = enabled;
if (isOwnerThread()) {
setFastScrollerEnabledUiThread(enabled);
} else {
post(new Runnable() {
@Override
public void run() {
setFastScrollerEnabledUiThread(enabled);
}
});
}
}
}
private void setFastScrollerEnabledUiThread(boolean enabled) {
if (mFastScroll != null) {
mFastScroll.setEnabled(enabled);
} else if (enabled) {
mFastScroll = new FastScroller(this, mFastScrollStyle);
mFastScroll.setEnabled(true);
}
resolvePadding();
if (mFastScroll != null) {
mFastScroll.updateLayout();
}
}
/**
* Specifies the style of the fast scroller decorations.
*
* @param styleResId style resource containing fast scroller properties
* @see android.R.styleable#FastScroll
*/
public void setFastScrollStyle(int styleResId) {
if (mFastScroll == null) {
mFastScrollStyle = styleResId;
} else {
mFastScroll.setStyle(styleResId);
}
}
/**
* Set whether or not the fast scroller should always be shown in place of
* the standard scroll bars. This will enable fast scrolling if it is not
* already enabled.
*
* Fast scrollers shown in this way will not fade out and will be a
* permanent fixture within the list. This is best combined with an inset
* scroll bar style to ensure the scroll bar does not overlap content.
*
* @param alwaysShow true if the fast scroller should always be displayed,
* false otherwise
* @see #setScrollBarStyle(int)
* @see #setFastScrollEnabled(boolean)
*/
public void setFastScrollAlwaysVisible(final boolean alwaysShow) {
if (mFastScrollAlwaysVisible != alwaysShow) {
if (alwaysShow && !mFastScrollEnabled) {
setFastScrollEnabled(true);
}
mFastScrollAlwaysVisible = alwaysShow;
if (isOwnerThread()) {
setFastScrollerAlwaysVisibleUiThread(alwaysShow);
} else {
post(new Runnable() {
@Override
public void run() {
setFastScrollerAlwaysVisibleUiThread(alwaysShow);
}
});
}
}
}
private void setFastScrollerAlwaysVisibleUiThread(boolean alwaysShow) {
if (mFastScroll != null) {
mFastScroll.setAlwaysShow(alwaysShow);
}
}
/**
* @return whether the current thread is the one that created the view
*/
private boolean isOwnerThread() {
return mOwnerThread == Thread.currentThread();
}
/**
* Returns true if the fast scroller is set to always show on this view.
*
* @return true if the fast scroller will always show
* @see #setFastScrollAlwaysVisible(boolean)
*/
public boolean isFastScrollAlwaysVisible() {
if (mFastScroll == null) {
return mFastScrollEnabled && mFastScrollAlwaysVisible;
} else {
return mFastScroll.isEnabled() && mFastScroll.isAlwaysShowEnabled();
}
}
@Override
public int getVerticalScrollbarWidth() {
if (mFastScroll != null && mFastScroll.isEnabled()) {
return Math.max(super.getVerticalScrollbarWidth(), mFastScroll.getWidth());
}
return super.getVerticalScrollbarWidth();
}
/**
* Returns true if the fast scroller is enabled.
*
* @see #setFastScrollEnabled(boolean)
* @return true if fast scroll is enabled, false otherwise
*/
@ViewDebug.ExportedProperty
@InspectableProperty
public boolean isFastScrollEnabled() {
if (mFastScroll == null) {
return mFastScrollEnabled;
} else {
return mFastScroll.isEnabled();
}
}
@Override
public void setVerticalScrollbarPosition(int position) {
super.setVerticalScrollbarPosition(position);
if (mFastScroll != null) {
mFastScroll.setScrollbarPosition(position);
}
}
@Override
public void setScrollBarStyle(int style) {
super.setScrollBarStyle(style);
if (mFastScroll != null) {
mFastScroll.setScrollBarStyle(style);
}
}
/**
* If fast scroll is enabled, then don't draw the vertical scrollbar.
* @hide
*/
@Override
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
protected boolean isVerticalScrollBarHidden() {
return isFastScrollEnabled();
}
/**
* When smooth scrollbar is enabled, the position and size of the scrollbar thumb
* is computed based on the number of visible pixels in the visible items. This
* however assumes that all list items have the same height. If you use a list in
* which items have different heights, the scrollbar will change appearance as the
* user scrolls through the list. To avoid this issue, you need to disable this
* property.
*
* When smooth scrollbar is disabled, the position and size of the scrollbar thumb
* is based solely on the number of items in the adapter and the position of the
* visible items inside the adapter. This provides a stable scrollbar as the user
* navigates through a list of items with varying heights.
*
* @param enabled Whether or not to enable smooth scrollbar.
*
* @see #setSmoothScrollbarEnabled(boolean)
* @attr ref android.R.styleable#AbsListView_smoothScrollbar
*/
public void setSmoothScrollbarEnabled(boolean enabled) {
mSmoothScrollbarEnabled = enabled;
}
/**
* Returns the current state of the fast scroll feature.
*
* @return True if smooth scrollbar is enabled is enabled, false otherwise.
*
* @see #setSmoothScrollbarEnabled(boolean)
*/
@ViewDebug.ExportedProperty
@InspectableProperty(name = "smoothScrollbar")
public boolean isSmoothScrollbarEnabled() {
return mSmoothScrollbarEnabled;
}
/**
* Set the listener that will receive notifications every time the list scrolls.
*
* @param l the scroll listener
*/
public void setOnScrollListener(OnScrollListener l) {
mOnScrollListener = l;
invokeOnItemScrollListener();
}
/**
* Notify our scroll listener (if there is one) of a change in scroll state
*/
@UnsupportedAppUsage
void invokeOnItemScrollListener() {
if (mFastScroll != null) {
mFastScroll.onScroll(mFirstPosition, getChildCount(), mItemCount);
}
if (mOnScrollListener != null) {
mOnScrollListener.onScroll(this, mFirstPosition, getChildCount(), mItemCount);
}
// placeholder values, View's implementation does not use these.
onScrollChanged(0, 0, 0, 0);
}
/**
* A TYPE_VIEW_SCROLLED event should be sent whenever a scroll happens, even if the
* mFirstPosition and the child count have not changed.
*/
@Override
public CharSequence getAccessibilityClassName() {
return AbsListView.class.getName();
}
/** @hide */
@Override
public void onInitializeAccessibilityNodeInfoInternal(AccessibilityNodeInfo info) {
super.onInitializeAccessibilityNodeInfoInternal(info);
if (isEnabled()) {
if (canScrollUp()) {
info.addAction(AccessibilityAction.ACTION_SCROLL_BACKWARD);
info.addAction(AccessibilityAction.ACTION_SCROLL_UP);
info.setScrollable(true);
}
if (canScrollDown()) {
info.addAction(AccessibilityAction.ACTION_SCROLL_FORWARD);
info.addAction(AccessibilityAction.ACTION_SCROLL_DOWN);
info.setScrollable(true);
}
}
info.removeAction(AccessibilityAction.ACTION_CLICK);
info.setClickable(false);
}
int getSelectionModeForAccessibility() {
final int choiceMode = getChoiceMode();
switch (choiceMode) {
case CHOICE_MODE_NONE:
return CollectionInfo.SELECTION_MODE_NONE;
case CHOICE_MODE_SINGLE:
return CollectionInfo.SELECTION_MODE_SINGLE;
case CHOICE_MODE_MULTIPLE:
case CHOICE_MODE_MULTIPLE_MODAL:
return CollectionInfo.SELECTION_MODE_MULTIPLE;
default:
return CollectionInfo.SELECTION_MODE_NONE;
}
}
/** @hide */
@Override
public boolean performAccessibilityActionInternal(int action, Bundle arguments) {
if (super.performAccessibilityActionInternal(action, arguments)) {
return true;
}
switch (action) {
case AccessibilityNodeInfo.ACTION_SCROLL_FORWARD:
case R.id.accessibilityActionScrollDown: {
if (isEnabled() && canScrollDown()) {
final int viewportHeight = getHeight() - mListPadding.top - mListPadding.bottom;
smoothScrollBy(viewportHeight, PositionScroller.SCROLL_DURATION);
return true;
}
} return false;
case AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD:
case R.id.accessibilityActionScrollUp: {
if (isEnabled() && canScrollUp()) {
final int viewportHeight = getHeight() - mListPadding.top - mListPadding.bottom;
smoothScrollBy(-viewportHeight, PositionScroller.SCROLL_DURATION);
return true;
}
} return false;
}
return false;
}
/**
* Indicates whether the children's drawing cache is used during a scroll.
* By default, the drawing cache is enabled but this will consume more memory.
*
* @return true if the scrolling cache is enabled, false otherwise
*
* @see #setScrollingCacheEnabled(boolean)
* @see View#setDrawingCacheEnabled(boolean)
*/
@ViewDebug.ExportedProperty
@InspectableProperty(name = "scrollingCache")
public boolean isScrollingCacheEnabled() {
return mScrollingCacheEnabled;
}
/**
* Enables or disables the children's drawing cache during a scroll.
* By default, the drawing cache is enabled but this will use more memory.
*
* When the scrolling cache is enabled, the caches are kept after the
* first scrolling. You can manually clear the cache by calling
* {@link android.view.ViewGroup#setChildrenDrawingCacheEnabled(boolean)}.
*
* @param enabled true to enable the scroll cache, false otherwise
*
* @see #isScrollingCacheEnabled()
* @see View#setDrawingCacheEnabled(boolean)
*/
public void setScrollingCacheEnabled(boolean enabled) {
if (mScrollingCacheEnabled && !enabled) {
clearScrollingCache();
}
mScrollingCacheEnabled = enabled;
}
/**
* Enables or disables the type filter window. If enabled, typing when
* this view has focus will filter the children to match the users input.
* Note that the {@link Adapter} used by this view must implement the
* {@link Filterable} interface.
*
* @param textFilterEnabled true to enable type filtering, false otherwise
*
* @see Filterable
*/
public void setTextFilterEnabled(boolean textFilterEnabled) {
mTextFilterEnabled = textFilterEnabled;
}
/**
* Indicates whether type filtering is enabled for this view
*
* @return true if type filtering is enabled, false otherwise
*
* @see #setTextFilterEnabled(boolean)
* @see Filterable
*/
@ViewDebug.ExportedProperty
@InspectableProperty
public boolean isTextFilterEnabled() {
return mTextFilterEnabled;
}
@Override
public void getFocusedRect(Rect r) {
View view = getSelectedView();
if (view != null && view.getParent() == this) {
// the focused rectangle of the selected view offset into the
// coordinate space of this view.
view.getFocusedRect(r);
offsetDescendantRectToMyCoords(view, r);
} else {
// otherwise, just the norm
super.getFocusedRect(r);
}
}
private void useDefaultSelector() {
setSelector(getContext().getDrawable(
com.android.internal.R.drawable.list_selector_background));
}
/**
* Indicates whether the content of this view is pinned to, or stacked from,
* the bottom edge.
*
* @return true if the content is stacked from the bottom edge, false otherwise
*/
@ViewDebug.ExportedProperty
@InspectableProperty
public boolean isStackFromBottom() {
return mStackFromBottom;
}
/**
* When stack from bottom is set to true, the list fills its content starting from
* the bottom of the view.
*
* @param stackFromBottom true to pin the view's content to the bottom edge,
* false to pin the view's content to the top edge
*/
public void setStackFromBottom(boolean stackFromBottom) {
if (mStackFromBottom != stackFromBottom) {
mStackFromBottom = stackFromBottom;
requestLayoutIfNecessary();
}
}
void requestLayoutIfNecessary() {
if (getChildCount() > 0) {
resetList();
requestLayout();
invalidate();
}
}
static class SavedState extends BaseSavedState {
long selectedId;
@UnsupportedAppUsage
long firstId;
@UnsupportedAppUsage
int viewTop;
int position;
int height;
String filter;
boolean inActionMode;
int checkedItemCount;
SparseBooleanArray checkState;
LongSparseArray checkIdState;
/**
* Constructor called from {@link AbsListView#onSaveInstanceState()}
*/
SavedState(Parcelable superState) {
super(superState);
}
/**
* Constructor called from {@link #CREATOR}
*/
private SavedState(Parcel in) {
super(in);
selectedId = in.readLong();
firstId = in.readLong();
viewTop = in.readInt();
position = in.readInt();
height = in.readInt();
filter = in.readString();
inActionMode = in.readByte() != 0;
checkedItemCount = in.readInt();
checkState = in.readSparseBooleanArray();
final int N = in.readInt();
if (N > 0) {
checkIdState = new LongSparseArray();
for (int i=0; i CREATOR
= new Parcelable.Creator() {
@Override
public SavedState createFromParcel(Parcel in) {
return new SavedState(in);
}
@Override
public SavedState[] newArray(int size) {
return new SavedState[size];
}
};
}
@Override
public Parcelable onSaveInstanceState() {
/*
* This doesn't really make sense as the place to dismiss the
* popups, but there don't seem to be any other useful hooks
* that happen early enough to keep from getting complaints
* about having leaked the window.
*/
dismissPopup();
Parcelable superState = super.onSaveInstanceState();
SavedState ss = new SavedState(superState);
if (mPendingSync != null) {
// Just keep what we last restored.
ss.selectedId = mPendingSync.selectedId;
ss.firstId = mPendingSync.firstId;
ss.viewTop = mPendingSync.viewTop;
ss.position = mPendingSync.position;
ss.height = mPendingSync.height;
ss.filter = mPendingSync.filter;
ss.inActionMode = mPendingSync.inActionMode;
ss.checkedItemCount = mPendingSync.checkedItemCount;
ss.checkState = mPendingSync.checkState;
ss.checkIdState = mPendingSync.checkIdState;
return ss;
}
boolean haveChildren = getChildCount() > 0 && mItemCount > 0;
long selectedId = getSelectedItemId();
ss.selectedId = selectedId;
ss.height = getHeight();
if (selectedId >= 0) {
// Remember the selection
ss.viewTop = mSelectedTop;
ss.position = getSelectedItemPosition();
ss.firstId = INVALID_POSITION;
} else {
if (haveChildren && mFirstPosition > 0) {
// Remember the position of the first child.
// We only do this if we are not currently at the top of
// the list, for two reasons:
// (1) The list may be in the process of becoming empty, in
// which case mItemCount may not be 0, but if we try to
// ask for any information about position 0 we will crash.
// (2) Being "at the top" seems like a special case, anyway,
// and the user wouldn't expect to end up somewhere else when
// they revisit the list even if its content has changed.
View v = getChildAt(0);
ss.viewTop = v.getTop();
int firstPos = mFirstPosition;
if (firstPos >= mItemCount) {
firstPos = mItemCount - 1;
}
ss.position = firstPos;
ss.firstId = mAdapter.getItemId(firstPos);
} else {
ss.viewTop = 0;
ss.firstId = INVALID_POSITION;
ss.position = 0;
}
}
ss.filter = null;
if (mFiltered) {
final EditText textFilter = mTextFilter;
if (textFilter != null) {
Editable filterText = textFilter.getText();
if (filterText != null) {
ss.filter = filterText.toString();
}
}
}
ss.inActionMode = mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode != null;
if (mCheckStates != null) {
ss.checkState = mCheckStates.clone();
}
if (mCheckedIdStates != null) {
final LongSparseArray idState = new LongSparseArray();
final int count = mCheckedIdStates.size();
for (int i = 0; i < count; i++) {
idState.put(mCheckedIdStates.keyAt(i), mCheckedIdStates.valueAt(i));
}
ss.checkIdState = idState;
}
ss.checkedItemCount = mCheckedItemCount;
if (mRemoteAdapter != null) {
mRemoteAdapter.saveRemoteViewsCache();
}
return ss;
}
@Override
public void onRestoreInstanceState(Parcelable state) {
SavedState ss = (SavedState) state;
super.onRestoreInstanceState(ss.getSuperState());
mDataChanged = true;
mSyncHeight = ss.height;
if (ss.selectedId >= 0) {
mNeedSync = true;
mPendingSync = ss;
mSyncRowId = ss.selectedId;
mSyncPosition = ss.position;
mSpecificTop = ss.viewTop;
mSyncMode = SYNC_SELECTED_POSITION;
} else if (ss.firstId >= 0) {
setSelectedPositionInt(INVALID_POSITION);
// Do this before setting mNeedSync since setNextSelectedPosition looks at mNeedSync
setNextSelectedPositionInt(INVALID_POSITION);
mSelectorPosition = INVALID_POSITION;
mNeedSync = true;
mPendingSync = ss;
mSyncRowId = ss.firstId;
mSyncPosition = ss.position;
mSpecificTop = ss.viewTop;
mSyncMode = SYNC_FIRST_POSITION;
}
setFilterText(ss.filter);
if (ss.checkState != null) {
mCheckStates = ss.checkState;
}
if (ss.checkIdState != null) {
mCheckedIdStates = ss.checkIdState;
}
mCheckedItemCount = ss.checkedItemCount;
if (ss.inActionMode && mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL &&
mMultiChoiceModeCallback != null) {
mChoiceActionMode = startActionMode(mMultiChoiceModeCallback);
}
requestLayout();
}
private boolean acceptFilter() {
return mTextFilterEnabled && getAdapter() instanceof Filterable &&
((Filterable) getAdapter()).getFilter() != null;
}
/**
* Sets the initial value for the text filter.
* @param filterText The text to use for the filter.
*
* @see #setTextFilterEnabled
*/
public void setFilterText(String filterText) {
// TODO: Should we check for acceptFilter()?
if (mTextFilterEnabled && !TextUtils.isEmpty(filterText)) {
createTextFilter(false);
// This is going to call our listener onTextChanged, but we might not
// be ready to bring up a window yet
mTextFilter.setText(filterText);
mTextFilter.setSelection(filterText.length());
if (mAdapter instanceof Filterable) {
// if mPopup is non-null, then onTextChanged will do the filtering
if (mPopup == null) {
Filter f = ((Filterable) mAdapter).getFilter();
f.filter(filterText);
}
// Set filtered to true so we will display the filter window when our main
// window is ready
mFiltered = true;
mDataSetObserver.clearSavedState();
}
}
}
/**
* Returns the list's text filter, if available.
* @return the list's text filter or null if filtering isn't enabled
*/
public CharSequence getTextFilter() {
if (mTextFilterEnabled && mTextFilter != null) {
return mTextFilter.getText();
}
return null;
}
@Override
protected void onFocusChanged(boolean gainFocus, int direction, Rect previouslyFocusedRect) {
super.onFocusChanged(gainFocus, direction, previouslyFocusedRect);
if (gainFocus && mSelectedPosition < 0 && !isInTouchMode()) {
if (!isAttachedToWindow() && mAdapter != null) {
// Data may have changed while we were detached and it's valid
// to change focus while detached. Refresh so we don't die.
mDataChanged = true;
mOldItemCount = mItemCount;
mItemCount = mAdapter.getCount();
}
resurrectSelection();
}
}
@Override
public void requestLayout() {
if (!mBlockLayoutRequests && !mInLayout) {
super.requestLayout();
}
}
/**
* The list is empty. Clear everything out.
*/
void resetList() {
removeAllViewsInLayout();
mFirstPosition = 0;
mDataChanged = false;
mPositionScrollAfterLayout = null;
mNeedSync = false;
mPendingSync = null;
mOldSelectedPosition = INVALID_POSITION;
mOldSelectedRowId = INVALID_ROW_ID;
setSelectedPositionInt(INVALID_POSITION);
setNextSelectedPositionInt(INVALID_POSITION);
mSelectedTop = 0;
mSelectorPosition = INVALID_POSITION;
mSelectorRect.setEmpty();
invalidate();
}
@Override
protected int computeVerticalScrollExtent() {
final int count = getChildCount();
if (count > 0) {
if (mSmoothScrollbarEnabled) {
int extent = count * 100;
View view = getChildAt(0);
final int top = view.getTop();
int height = view.getHeight();
if (height > 0) {
extent += (top * 100) / height;
}
view = getChildAt(count - 1);
final int bottom = view.getBottom();
height = view.getHeight();
if (height > 0) {
extent -= ((bottom - getHeight()) * 100) / height;
}
return extent;
} else {
return 1;
}
}
return 0;
}
@Override
protected int computeVerticalScrollOffset() {
final int firstPosition = mFirstPosition;
final int childCount = getChildCount();
if (firstPosition >= 0 && childCount > 0) {
if (mSmoothScrollbarEnabled) {
final View view = getChildAt(0);
final int top = view.getTop();
int height = view.getHeight();
if (height > 0) {
return Math.max(firstPosition * 100 - (top * 100) / height +
(int)((float)mScrollY / getHeight() * mItemCount * 100), 0);
}
} else {
int index;
final int count = mItemCount;
if (firstPosition == 0) {
index = 0;
} else if (firstPosition + childCount == count) {
index = count;
} else {
index = firstPosition + childCount / 2;
}
return (int) (firstPosition + childCount * (index / (float) count));
}
}
return 0;
}
@Override
protected int computeVerticalScrollRange() {
int result;
if (mSmoothScrollbarEnabled) {
result = Math.max(mItemCount * 100, 0);
if (mScrollY != 0) {
// Compensate for overscroll
result += Math.abs((int) ((float) mScrollY / getHeight() * mItemCount * 100));
}
} else {
result = mItemCount;
}
return result;
}
@Override
protected float getTopFadingEdgeStrength() {
final int count = getChildCount();
final float fadeEdge = super.getTopFadingEdgeStrength();
if (count == 0) {
return fadeEdge;
} else {
if (mFirstPosition > 0) {
return 1.0f;
}
final int top = getChildAt(0).getTop();
final float fadeLength = getVerticalFadingEdgeLength();
return top < mPaddingTop ? -(top - mPaddingTop) / fadeLength : fadeEdge;
}
}
@Override
protected float getBottomFadingEdgeStrength() {
final int count = getChildCount();
final float fadeEdge = super.getBottomFadingEdgeStrength();
if (count == 0) {
return fadeEdge;
} else {
if (mFirstPosition + count - 1 < mItemCount - 1) {
return 1.0f;
}
final int bottom = getChildAt(count - 1).getBottom();
final int height = getHeight();
final float fadeLength = getVerticalFadingEdgeLength();
return bottom > height - mPaddingBottom ?
(bottom - height + mPaddingBottom) / fadeLength : fadeEdge;
}
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
if (mSelector == null) {
useDefaultSelector();
}
final Rect listPadding = mListPadding;
listPadding.left = mSelectionLeftPadding + mPaddingLeft;
listPadding.top = mSelectionTopPadding + mPaddingTop;
listPadding.right = mSelectionRightPadding + mPaddingRight;
listPadding.bottom = mSelectionBottomPadding + mPaddingBottom;
// Check if our previous measured size was at a point where we should scroll later.
if (mTranscriptMode == TRANSCRIPT_MODE_NORMAL) {
final int childCount = getChildCount();
final int listBottom = getHeight() - getPaddingBottom();
final View lastChild = getChildAt(childCount - 1);
final int lastBottom = lastChild != null ? lastChild.getBottom() : listBottom;
mForceTranscriptScroll = mFirstPosition + childCount >= mLastHandledItemCount &&
lastBottom <= listBottom;
}
}
/**
* Subclasses should NOT override this method but
* {@link #layoutChildren()} instead.
*/
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
super.onLayout(changed, l, t, r, b);
mInLayout = true;
final int childCount = getChildCount();
if (changed) {
for (int i = 0; i < childCount; i++) {
getChildAt(i).forceLayout();
}
mRecycler.markChildrenDirty();
}
layoutChildren();
mOverscrollMax = (b - t) / OVERSCROLL_LIMIT_DIVISOR;
// TODO: Move somewhere sane. This doesn't belong in onLayout().
if (mFastScroll != null) {
mFastScroll.onItemCountChanged(getChildCount(), mItemCount);
}
mInLayout = false;
}
/**
* @hide
*/
@Override
protected boolean setFrame(int left, int top, int right, int bottom) {
final boolean changed = super.setFrame(left, top, right, bottom);
if (changed) {
// Reposition the popup when the frame has changed. This includes
// translating the widget, not just changing its dimension. The
// filter popup needs to follow the widget.
final boolean visible = getWindowVisibility() == View.VISIBLE;
if (mFiltered && visible && mPopup != null && mPopup.isShowing()) {
positionPopup();
}
}
return changed;
}
/**
* Subclasses must override this method to layout their children.
*/
protected void layoutChildren() {
}
/**
* @param focusedView view that holds accessibility focus
* @return direct child that contains accessibility focus, or null if no
* child contains accessibility focus
*/
View getAccessibilityFocusedChild(View focusedView) {
ViewParent viewParent = focusedView.getParent();
while ((viewParent instanceof View) && (viewParent != this)) {
focusedView = (View) viewParent;
viewParent = viewParent.getParent();
}
if (!(viewParent instanceof View)) {
return null;
}
return focusedView;
}
void updateScrollIndicators() {
if (mScrollUp != null) {
mScrollUp.setVisibility(canScrollUp() ? View.VISIBLE : View.INVISIBLE);
}
if (mScrollDown != null) {
mScrollDown.setVisibility(canScrollDown() ? View.VISIBLE : View.INVISIBLE);
}
}
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
private boolean canScrollUp() {
boolean canScrollUp;
// 0th element is not visible
canScrollUp = mFirstPosition > 0;
// ... Or top of 0th element is not visible
if (!canScrollUp) {
if (getChildCount() > 0) {
View child = getChildAt(0);
canScrollUp = child.getTop() < mListPadding.top;
}
}
return canScrollUp;
}
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
private boolean canScrollDown() {
boolean canScrollDown;
int count = getChildCount();
// Last item is not visible
canScrollDown = (mFirstPosition + count) < mItemCount;
// ... Or bottom of the last element is not visible
if (!canScrollDown && count > 0) {
View child = getChildAt(count - 1);
canScrollDown = child.getBottom() > mBottom - mListPadding.bottom;
}
return canScrollDown;
}
@Override
@ViewDebug.ExportedProperty
public View getSelectedView() {
if (mItemCount > 0 && mSelectedPosition >= 0) {
return getChildAt(mSelectedPosition - mFirstPosition);
} else {
return null;
}
}
/**
* List padding is the maximum of the normal view's padding and the padding of the selector.
*
* @see android.view.View#getPaddingTop()
* @see #getSelector()
*
* @return The top list padding.
*/
public int getListPaddingTop() {
return mListPadding.top;
}
/**
* List padding is the maximum of the normal view's padding and the padding of the selector.
*
* @see android.view.View#getPaddingBottom()
* @see #getSelector()
*
* @return The bottom list padding.
*/
public int getListPaddingBottom() {
return mListPadding.bottom;
}
/**
* List padding is the maximum of the normal view's padding and the padding of the selector.
*
* @see android.view.View#getPaddingLeft()
* @see #getSelector()
*
* @return The left list padding.
*/
public int getListPaddingLeft() {
return mListPadding.left;
}
/**
* List padding is the maximum of the normal view's padding and the padding of the selector.
*
* @see android.view.View#getPaddingRight()
* @see #getSelector()
*
* @return The right list padding.
*/
public int getListPaddingRight() {
return mListPadding.right;
}
/**
* Gets a view and have it show the data associated with the specified
* position. This is called when we have already discovered that the view
* is not available for reuse in the recycle bin. The only choices left are
* converting an old view or making a new one.
*
* @param position the position to display
* @param outMetadata an array of at least 1 boolean where the first entry
* will be set {@code true} if the view is currently
* attached to the window, {@code false} otherwise (e.g.
* newly-inflated or remained scrap for multiple layout
* passes)
*
* @return A view displaying the data associated with the specified position
*/
View obtainView(int position, boolean[] outMetadata) {
Trace.traceBegin(Trace.TRACE_TAG_VIEW, "obtainView");
outMetadata[0] = false;
// Check whether we have a transient state view. Attempt to re-bind the
// data and discard the view if we fail.
final View transientView = mRecycler.getTransientStateView(position);
if (transientView != null) {
final LayoutParams params = (LayoutParams) transientView.getLayoutParams();
// If the view type hasn't changed, attempt to re-bind the data.
if (params.viewType == mAdapter.getItemViewType(position)) {
final View updatedView = mAdapter.getView(position, transientView, this);
// If we failed to re-bind the data, scrap the obtained view.
if (updatedView != transientView) {
setItemViewLayoutParams(updatedView, position);
mRecycler.addScrapView(updatedView, position);
}
}
outMetadata[0] = true;
// Finish the temporary detach started in addScrapView().
transientView.dispatchFinishTemporaryDetach();
return transientView;
}
final View scrapView = mRecycler.getScrapView(position);
final View child = mAdapter.getView(position, scrapView, this);
if (scrapView != null) {
if (child != scrapView) {
// Failed to re-bind the data, return scrap to the heap.
mRecycler.addScrapView(scrapView, position);
} else if (child.isTemporarilyDetached()) {
outMetadata[0] = true;
// Finish the temporary detach started in addScrapView().
child.dispatchFinishTemporaryDetach();
}
}
if (mCacheColorHint != 0) {
child.setDrawingCacheBackgroundColor(mCacheColorHint);
}
if (child.getImportantForAccessibility() == IMPORTANT_FOR_ACCESSIBILITY_AUTO) {
child.setImportantForAccessibility(IMPORTANT_FOR_ACCESSIBILITY_YES);
}
setItemViewLayoutParams(child, position);
if (AccessibilityManager.getInstance(mContext).isEnabled()) {
if (mAccessibilityDelegate == null) {
mAccessibilityDelegate = new ListItemAccessibilityDelegate();
}
if (child.getAccessibilityDelegate() == null) {
child.setAccessibilityDelegate(mAccessibilityDelegate);
}
}
Trace.traceEnd(Trace.TRACE_TAG_VIEW);
return child;
}
private void setItemViewLayoutParams(View child, int position) {
final ViewGroup.LayoutParams vlp = child.getLayoutParams();
LayoutParams lp;
if (vlp == null) {
lp = (LayoutParams) generateDefaultLayoutParams();
} else if (!checkLayoutParams(vlp)) {
lp = (LayoutParams) generateLayoutParams(vlp);
} else {
lp = (LayoutParams) vlp;
}
if (mAdapterHasStableIds) {
lp.itemId = mAdapter.getItemId(position);
}
lp.viewType = mAdapter.getItemViewType(position);
lp.isEnabled = mAdapter.isEnabled(position);
if (lp != vlp) {
child.setLayoutParams(lp);
}
}
class ListItemAccessibilityDelegate extends AccessibilityDelegate {
@Override
public void onInitializeAccessibilityNodeInfo(View host, AccessibilityNodeInfo info) {
super.onInitializeAccessibilityNodeInfo(host, info);
final int position = getPositionForView(host);
onInitializeAccessibilityNodeInfoForItem(host, position, info);
}
@Override
public boolean performAccessibilityAction(View host, int action, Bundle arguments) {
if (super.performAccessibilityAction(host, action, arguments)) {
return true;
}
final int position = getPositionForView(host);
if (position == INVALID_POSITION || mAdapter == null) {
// Cannot perform actions on invalid items.
return false;
}
if (position >= mAdapter.getCount()) {
// The position is no longer valid, likely due to a data set
// change. We could fail here for all data set changes, since
// there is a chance that the data bound to the view may no
// longer exist at the same position within the adapter, but
// it's more consistent with the standard touch interaction to
// click at whatever may have moved into that position.
return false;
}
final boolean isItemEnabled;
final ViewGroup.LayoutParams lp = host.getLayoutParams();
if (lp instanceof AbsListView.LayoutParams) {
isItemEnabled = ((AbsListView.LayoutParams) lp).isEnabled;
} else {
isItemEnabled = false;
}
if (!isEnabled() || !isItemEnabled) {
// Cannot perform actions on disabled items.
return false;
}
switch (action) {
case AccessibilityNodeInfo.ACTION_CLEAR_SELECTION: {
if (getSelectedItemPosition() == position) {
setSelection(INVALID_POSITION);
return true;
}
} return false;
case AccessibilityNodeInfo.ACTION_SELECT: {
if (getSelectedItemPosition() != position) {
setSelection(position);
return true;
}
} return false;
case AccessibilityNodeInfo.ACTION_CLICK: {
if (isItemClickable(host)) {
final long id = getItemIdAtPosition(position);
return performItemClick(host, position, id);
}
} return false;
case AccessibilityNodeInfo.ACTION_LONG_CLICK: {
if (isLongClickable()) {
final long id = getItemIdAtPosition(position);
return performLongPress(host, position, id);
}
} return false;
}
return false;
}
}
/**
* Initializes an {@link AccessibilityNodeInfo} with information about a
* particular item in the list.
*
* @param view View representing the list item.
* @param position Position of the list item within the adapter.
* @param info Node info to populate.
*/
public void onInitializeAccessibilityNodeInfoForItem(
View view, int position, AccessibilityNodeInfo info) {
if (position == INVALID_POSITION) {
// The item doesn't exist, so there's not much we can do here.
return;
}
boolean isItemEnabled = view.isEnabled() && isEnabled();
final ViewGroup.LayoutParams lp = view.getLayoutParams();
if (lp instanceof AbsListView.LayoutParams) {
isItemEnabled &= ((AbsListView.LayoutParams) lp).isEnabled;
}
info.setEnabled(isItemEnabled);
if (position == getSelectedItemPosition()) {
info.setSelected(true);
addAccessibilityActionIfEnabled(info, isItemEnabled,
AccessibilityAction.ACTION_CLEAR_SELECTION);
} else {
addAccessibilityActionIfEnabled(info, isItemEnabled,
AccessibilityAction.ACTION_SELECT);
}
if (isItemClickable(view)) {
addAccessibilityActionIfEnabled(info, isItemEnabled, AccessibilityAction.ACTION_CLICK);
// A disabled item is a separator which should not be clickable.
info.setClickable(isItemEnabled);
}
if (isLongClickable()) {
addAccessibilityActionIfEnabled(info, isItemEnabled,
AccessibilityAction.ACTION_LONG_CLICK);
info.setLongClickable(true);
}
}
private void addAccessibilityActionIfEnabled(AccessibilityNodeInfo info, boolean enabled,
AccessibilityAction action) {
if (enabled) {
info.addAction(action);
}
}
private boolean isItemClickable(View view) {
return !view.hasExplicitFocusable();
}
/**
* Positions the selector in a way that mimics touch.
*/
void positionSelectorLikeTouch(int position, View sel, float x, float y) {
positionSelector(position, sel, true, x, y);
}
/**
* Positions the selector in a way that mimics keyboard focus.
*/
void positionSelectorLikeFocus(int position, View sel) {
if (mSelector != null && mSelectorPosition != position && position != INVALID_POSITION) {
final Rect bounds = mSelectorRect;
final float x = bounds.exactCenterX();
final float y = bounds.exactCenterY();
positionSelector(position, sel, true, x, y);
} else {
positionSelector(position, sel);
}
}
void positionSelector(int position, View sel) {
positionSelector(position, sel, false, -1, -1);
}
@UnsupportedAppUsage
private void positionSelector(int position, View sel, boolean manageHotspot, float x, float y) {
final boolean positionChanged = position != mSelectorPosition;
if (position != INVALID_POSITION) {
mSelectorPosition = position;
}
final Rect selectorRect = mSelectorRect;
selectorRect.set(sel.getLeft(), sel.getTop(), sel.getRight(), sel.getBottom());
if (sel instanceof SelectionBoundsAdjuster) {
((SelectionBoundsAdjuster)sel).adjustListItemSelectionBounds(selectorRect);
}
// Adjust for selection padding.
selectorRect.left -= mSelectionLeftPadding;
selectorRect.top -= mSelectionTopPadding;
selectorRect.right += mSelectionRightPadding;
selectorRect.bottom += mSelectionBottomPadding;
// Update the child enabled state prior to updating the selector.
final boolean isChildViewEnabled = sel.isEnabled();
if (mIsChildViewEnabled != isChildViewEnabled) {
mIsChildViewEnabled = isChildViewEnabled;
}
// Update the selector drawable's state and position.
final Drawable selector = mSelector;
if (selector != null) {
if (positionChanged) {
// Wipe out the current selector state so that we can start
// over in the new position with a fresh state.
selector.setVisible(false, false);
selector.setState(StateSet.NOTHING);
}
selector.setBounds(selectorRect);
if (positionChanged) {
if (getVisibility() == VISIBLE) {
selector.setVisible(true, false);
}
updateSelectorState();
}
if (manageHotspot) {
selector.setHotspot(x, y);
}
}
}
@Override
protected void dispatchDraw(Canvas canvas) {
int saveCount = 0;
final boolean clipToPadding = (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK;
if (clipToPadding) {
saveCount = canvas.save();
final int scrollX = mScrollX;
final int scrollY = mScrollY;
canvas.clipRect(scrollX + mPaddingLeft, scrollY + mPaddingTop,
scrollX + mRight - mLeft - mPaddingRight,
scrollY + mBottom - mTop - mPaddingBottom);
mGroupFlags &= ~CLIP_TO_PADDING_MASK;
}
final boolean drawSelectorOnTop = mDrawSelectorOnTop;
if (!drawSelectorOnTop) {
drawSelector(canvas);
}
super.dispatchDraw(canvas);
if (drawSelectorOnTop) {
drawSelector(canvas);
}
if (clipToPadding) {
canvas.restoreToCount(saveCount);
mGroupFlags |= CLIP_TO_PADDING_MASK;
}
}
@Override
protected boolean isPaddingOffsetRequired() {
return (mGroupFlags & CLIP_TO_PADDING_MASK) != CLIP_TO_PADDING_MASK;
}
@Override
protected int getLeftPaddingOffset() {
return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : -mPaddingLeft;
}
@Override
protected int getTopPaddingOffset() {
return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : -mPaddingTop;
}
@Override
protected int getRightPaddingOffset() {
return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : mPaddingRight;
}
@Override
protected int getBottomPaddingOffset() {
return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : mPaddingBottom;
}
/**
* @hide
*/
@Override
protected void internalSetPadding(int left, int top, int right, int bottom) {
super.internalSetPadding(left, top, right, bottom);
if (isLayoutRequested()) {
handleBoundsChange();
}
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
handleBoundsChange();
if (mFastScroll != null) {
mFastScroll.onSizeChanged(w, h, oldw, oldh);
}
}
/**
* Called when bounds of the AbsListView are changed. AbsListView marks data set as changed
* and force layouts all children that don't have exact measure specs.
*
* This invalidation is necessary, otherwise, AbsListView may think the children are valid and
* fail to relayout them properly to accommodate for new bounds.
*/
void handleBoundsChange() {
if (mInLayout) {
return;
}
final int childCount = getChildCount();
if (childCount > 0) {
mDataChanged = true;
rememberSyncState();
for (int i = 0; i < childCount; i++) {
final View child = getChildAt(i);
final ViewGroup.LayoutParams lp = child.getLayoutParams();
// force layout child unless it has exact specs
if (lp == null || lp.width < 1 || lp.height < 1) {
child.forceLayout();
}
}
}
}
/**
* @return True if the current touch mode requires that we draw the selector in the pressed
* state.
*/
boolean touchModeDrawsInPressedState() {
// FIXME use isPressed for this
switch (mTouchMode) {
case TOUCH_MODE_TAP:
case TOUCH_MODE_DONE_WAITING:
return true;
default:
return false;
}
}
/**
* Indicates whether this view is in a state where the selector should be drawn. This will
* happen if we have focus but are not in touch mode, or we are in the middle of displaying
* the pressed state for an item.
*
* @return True if the selector should be shown
*/
boolean shouldShowSelector() {
return (isFocused() && !isInTouchMode()) || (touchModeDrawsInPressedState() && isPressed());
}
private void drawSelector(Canvas canvas) {
if (shouldDrawSelector()) {
final Drawable selector = mSelector;
selector.setBounds(mSelectorRect);
selector.draw(canvas);
}
}
/**
* @hide
*/
@TestApi
public final boolean shouldDrawSelector() {
return !mSelectorRect.isEmpty();
}
/**
* Controls whether the selection highlight drawable should be drawn on top of the item or
* behind it.
*
* @param onTop If true, the selector will be drawn on the item it is highlighting. The default
* is false.
*
* @attr ref android.R.styleable#AbsListView_drawSelectorOnTop
*/
public void setDrawSelectorOnTop(boolean onTop) {
mDrawSelectorOnTop = onTop;
}
/**
* Returns whether the selection highlight drawable should be drawn on top of the item or
* behind it.
*
* @return true if selector is drawn on top, false otherwise
* @attr ref android.R.styleable#AbsListView_drawSelectorOnTop
*/
@InspectableProperty
public boolean isDrawSelectorOnTop() {
return mDrawSelectorOnTop;
}
/**
* Set a Drawable that should be used to highlight the currently selected item.
*
* @param resID A Drawable resource to use as the selection highlight.
*
* @attr ref android.R.styleable#AbsListView_listSelector
*/
public void setSelector(@DrawableRes int resID) {
setSelector(getContext().getDrawable(resID));
}
public void setSelector(Drawable sel) {
if (mSelector != null) {
mSelector.setCallback(null);
unscheduleDrawable(mSelector);
}
mSelector = sel;
Rect padding = new Rect();
sel.getPadding(padding);
mSelectionLeftPadding = padding.left;
mSelectionTopPadding = padding.top;
mSelectionRightPadding = padding.right;
mSelectionBottomPadding = padding.bottom;
sel.setCallback(this);
updateSelectorState();
}
/**
* Returns the selector {@link android.graphics.drawable.Drawable} that is used to draw the
* selection in the list.
*
* @return the drawable used to display the selector
*/
@InspectableProperty(name = "listSelector")
public Drawable getSelector() {
return mSelector;
}
/**
* Sets the selector state to "pressed" and posts a CheckForKeyLongPress to see if
* this is a long press.
*/
void keyPressed() {
if (!isEnabled() || !isClickable()) {
return;
}
Drawable selector = mSelector;
Rect selectorRect = mSelectorRect;
if (selector != null && (isFocused() || touchModeDrawsInPressedState())
&& !selectorRect.isEmpty()) {
final View v = getChildAt(mSelectedPosition - mFirstPosition);
if (v != null) {
if (v.hasExplicitFocusable()) return;
v.setPressed(true);
}
setPressed(true);
final boolean longClickable = isLongClickable();
Drawable d = selector.getCurrent();
if (d != null && d instanceof TransitionDrawable) {
if (longClickable) {
((TransitionDrawable) d).startTransition(
ViewConfiguration.getLongPressTimeout());
} else {
((TransitionDrawable) d).resetTransition();
}
}
if (longClickable && !mDataChanged) {
if (mPendingCheckForKeyLongPress == null) {
mPendingCheckForKeyLongPress = new CheckForKeyLongPress();
}
mPendingCheckForKeyLongPress.rememberWindowAttachCount();
postDelayed(mPendingCheckForKeyLongPress, ViewConfiguration.getLongPressTimeout());
}
}
}
public void setScrollIndicators(View up, View down) {
mScrollUp = up;
mScrollDown = down;
}
@UnsupportedAppUsage
void updateSelectorState() {
final Drawable selector = mSelector;
if (selector != null && selector.isStateful()) {
if (shouldShowSelector()) {
if (selector.setState(getDrawableStateForSelector())) {
invalidateDrawable(selector);
}
} else {
selector.setState(StateSet.NOTHING);
}
}
}
@Override
protected void drawableStateChanged() {
super.drawableStateChanged();
updateSelectorState();
}
private int[] getDrawableStateForSelector() {
// If the child view is enabled then do the default behavior.
if (mIsChildViewEnabled) {
// Common case
return super.getDrawableState();
}
// The selector uses this View's drawable state. The selected child view
// is disabled, so we need to remove the enabled state from the drawable
// states.
final int enabledState = ENABLED_STATE_SET[0];
// If we don't have any extra space, it will return one of the static
// state arrays, and clearing the enabled state on those arrays is a
// bad thing! If we specify we need extra space, it will create+copy
// into a new array that is safely mutable.
final int[] state = onCreateDrawableState(1);
int enabledPos = -1;
for (int i = state.length - 1; i >= 0; i--) {
if (state[i] == enabledState) {
enabledPos = i;
break;
}
}
// Remove the enabled state
if (enabledPos >= 0) {
System.arraycopy(state, enabledPos + 1, state, enabledPos,
state.length - enabledPos - 1);
}
return state;
}
@Override
public boolean verifyDrawable(@NonNull Drawable dr) {
return mSelector == dr || super.verifyDrawable(dr);
}
@Override
public void jumpDrawablesToCurrentState() {
super.jumpDrawablesToCurrentState();
if (mSelector != null) mSelector.jumpToCurrentState();
}
@Override
protected void onAttachedToWindow() {
super.onAttachedToWindow();
final ViewTreeObserver treeObserver = getViewTreeObserver();
treeObserver.addOnTouchModeChangeListener(this);
if (mTextFilterEnabled && mPopup != null && !mGlobalLayoutListenerAddedFilter) {
treeObserver.addOnGlobalLayoutListener(this);
}
if (mAdapter != null && mDataSetObserver == null) {
mDataSetObserver = new AdapterDataSetObserver();
mAdapter.registerDataSetObserver(mDataSetObserver);
// Data may have changed while we were detached. Refresh.
mDataChanged = true;
mOldItemCount = mItemCount;
mItemCount = mAdapter.getCount();
}
}
@Override
protected void onDetachedFromWindow() {
super.onDetachedFromWindow();
mIsDetaching = true;
// Dismiss the popup in case onSaveInstanceState() was not invoked
dismissPopup();
// Detach any view left in the scrap heap
mRecycler.clear();
final ViewTreeObserver treeObserver = getViewTreeObserver();
treeObserver.removeOnTouchModeChangeListener(this);
if (mTextFilterEnabled && mPopup != null) {
treeObserver.removeOnGlobalLayoutListener(this);
mGlobalLayoutListenerAddedFilter = false;
}
if (mAdapter != null && mDataSetObserver != null) {
mAdapter.unregisterDataSetObserver(mDataSetObserver);
mDataSetObserver = null;
}
if (mScrollStrictSpan != null) {
mScrollStrictSpan.finish();
mScrollStrictSpan = null;
}
if (mFlingStrictSpan != null) {
mFlingStrictSpan.finish();
mFlingStrictSpan = null;
}
if (mFlingRunnable != null) {
removeCallbacks(mFlingRunnable);
}
if (mPositionScroller != null) {
mPositionScroller.stop();
}
if (mClearScrollingCache != null) {
removeCallbacks(mClearScrollingCache);
}
if (mPerformClick != null) {
removeCallbacks(mPerformClick);
}
if (mTouchModeReset != null) {
removeCallbacks(mTouchModeReset);
mTouchModeReset.run();
}
mIsDetaching = false;
}
@Override
public void onWindowFocusChanged(boolean hasWindowFocus) {
super.onWindowFocusChanged(hasWindowFocus);
final int touchMode = isInTouchMode() ? TOUCH_MODE_ON : TOUCH_MODE_OFF;
if (!hasWindowFocus) {
setChildrenDrawingCacheEnabled(false);
if (mFlingRunnable != null) {
removeCallbacks(mFlingRunnable);
// let the fling runnable report its new state which
// should be idle
mFlingRunnable.mSuppressIdleStateChangeCall = false;
mFlingRunnable.endFling();
if (mPositionScroller != null) {
mPositionScroller.stop();
}
if (mScrollY != 0) {
mScrollY = 0;
invalidateParentCaches();
finishGlows();
invalidate();
}
}
// Always hide the type filter
dismissPopup();
if (touchMode == TOUCH_MODE_OFF) {
// Remember the last selected element
mResurrectToPosition = mSelectedPosition;
}
} else {
if (mFiltered && !mPopupHidden) {
// Show the type filter only if a filter is in effect
showPopup();
}
// If we changed touch mode since the last time we had focus
if (touchMode != mLastTouchMode && mLastTouchMode != TOUCH_MODE_UNKNOWN) {
// If we come back in trackball mode, we bring the selection back
if (touchMode == TOUCH_MODE_OFF) {
// This will trigger a layout
resurrectSelection();
// If we come back in touch mode, then we want to hide the selector
} else {
hideSelector();
mLayoutMode = LAYOUT_NORMAL;
layoutChildren();
}
}
}
mLastTouchMode = touchMode;
}
@Override
public void onRtlPropertiesChanged(int layoutDirection) {
super.onRtlPropertiesChanged(layoutDirection);
if (mFastScroll != null) {
mFastScroll.setScrollbarPosition(getVerticalScrollbarPosition());
}
}
/**
* Creates the ContextMenuInfo returned from {@link #getContextMenuInfo()}. This
* methods knows the view, position and ID of the item that received the
* long press.
*
* @param view The view that received the long press.
* @param position The position of the item that received the long press.
* @param id The ID of the item that received the long press.
* @return The extra information that should be returned by
* {@link #getContextMenuInfo()}.
*/
ContextMenuInfo createContextMenuInfo(View view, int position, long id) {
return new AdapterContextMenuInfo(view, position, id);
}
@Override
public void onCancelPendingInputEvents() {
super.onCancelPendingInputEvents();
if (mPerformClick != null) {
removeCallbacks(mPerformClick);
}
if (mPendingCheckForTap != null) {
removeCallbacks(mPendingCheckForTap);
}
if (mPendingCheckForLongPress != null) {
removeCallbacks(mPendingCheckForLongPress);
}
if (mPendingCheckForKeyLongPress != null) {
removeCallbacks(mPendingCheckForKeyLongPress);
}
}
/**
* A base class for Runnables that will check that their view is still attached to
* the original window as when the Runnable was created.
*
*/
private class WindowRunnnable {
private int mOriginalAttachCount;
public void rememberWindowAttachCount() {
mOriginalAttachCount = getWindowAttachCount();
}
public boolean sameWindow() {
return getWindowAttachCount() == mOriginalAttachCount;
}
}
private class PerformClick extends WindowRunnnable implements Runnable {
int mClickMotionPosition;
@Override
public void run() {
// The data has changed since we posted this action in the event queue,
// bail out before bad things happen
if (mDataChanged) return;
final ListAdapter adapter = mAdapter;
final int motionPosition = mClickMotionPosition;
if (adapter != null && mItemCount > 0 &&
motionPosition != INVALID_POSITION &&
motionPosition < adapter.getCount() && sameWindow() &&
adapter.isEnabled(motionPosition)) {
final View view = getChildAt(motionPosition - mFirstPosition);
// If there is no view, something bad happened (the view scrolled off the
// screen, etc.) and we should cancel the click
if (view != null) {
performItemClick(view, motionPosition, adapter.getItemId(motionPosition));
}
}
}
}
private class CheckForLongPress extends WindowRunnnable implements Runnable {
private static final int INVALID_COORD = -1;
private float mX = INVALID_COORD;
private float mY = INVALID_COORD;
private void setCoords(float x, float y) {
mX = x;
mY = y;
}
@Override
public void run() {
final int motionPosition = mMotionPosition;
final View child = getChildAt(motionPosition - mFirstPosition);
if (child != null) {
final int longPressPosition = mMotionPosition;
final long longPressId = mAdapter.getItemId(mMotionPosition);
boolean handled = false;
if (sameWindow() && !mDataChanged) {
if (mX != INVALID_COORD && mY != INVALID_COORD) {
handled = performLongPress(child, longPressPosition, longPressId, mX, mY);
} else {
handled = performLongPress(child, longPressPosition, longPressId);
}
}
if (handled) {
mHasPerformedLongPress = true;
mTouchMode = TOUCH_MODE_REST;
setPressed(false);
child.setPressed(false);
} else {
mTouchMode = TOUCH_MODE_DONE_WAITING;
}
}
}
}
private class CheckForKeyLongPress extends WindowRunnnable implements Runnable {
@Override
public void run() {
if (isPressed() && mSelectedPosition >= 0) {
int index = mSelectedPosition - mFirstPosition;
View v = getChildAt(index);
if (!mDataChanged) {
boolean handled = false;
if (sameWindow()) {
handled = performLongPress(v, mSelectedPosition, mSelectedRowId);
}
if (handled) {
setPressed(false);
v.setPressed(false);
}
} else {
setPressed(false);
if (v != null) v.setPressed(false);
}
}
}
}
private boolean performStylusButtonPressAction(MotionEvent ev) {
if (mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode == null) {
final View child = getChildAt(mMotionPosition - mFirstPosition);
if (child != null) {
final int longPressPosition = mMotionPosition;
final long longPressId = mAdapter.getItemId(mMotionPosition);
if (performLongPress(child, longPressPosition, longPressId)) {
mTouchMode = TOUCH_MODE_REST;
setPressed(false);
child.setPressed(false);
return true;
}
}
}
return false;
}
@UnsupportedAppUsage
boolean performLongPress(final View child,
final int longPressPosition, final long longPressId) {
return performLongPress(
child,
longPressPosition,
longPressId,
CheckForLongPress.INVALID_COORD,
CheckForLongPress.INVALID_COORD);
}
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
boolean performLongPress(final View child,
final int longPressPosition, final long longPressId, float x, float y) {
// CHOICE_MODE_MULTIPLE_MODAL takes over long press.
if (mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL) {
if (mChoiceActionMode == null &&
(mChoiceActionMode = startActionMode(mMultiChoiceModeCallback)) != null) {
setItemChecked(longPressPosition, true);
performHapticFeedback(HapticFeedbackConstants.LONG_PRESS);
}
return true;
}
boolean handled = false;
if (mOnItemLongClickListener != null) {
handled = mOnItemLongClickListener.onItemLongClick(AbsListView.this, child,
longPressPosition, longPressId);
}
if (!handled) {
mContextMenuInfo = createContextMenuInfo(child, longPressPosition, longPressId);
if (x != CheckForLongPress.INVALID_COORD && y != CheckForLongPress.INVALID_COORD) {
handled = super.showContextMenuForChild(AbsListView.this, x, y);
} else {
handled = super.showContextMenuForChild(AbsListView.this);
}
}
if (handled) {
performHapticFeedback(HapticFeedbackConstants.LONG_PRESS);
}
return handled;
}
@Override
protected ContextMenuInfo getContextMenuInfo() {
return mContextMenuInfo;
}
@Override
public boolean showContextMenu() {
return showContextMenuInternal(0, 0, false);
}
@Override
public boolean showContextMenu(float x, float y) {
return showContextMenuInternal(x, y, true);
}
private boolean showContextMenuInternal(float x, float y, boolean useOffsets) {
final int position = pointToPosition((int)x, (int)y);
if (position != INVALID_POSITION) {
final long id = mAdapter.getItemId(position);
View child = getChildAt(position - mFirstPosition);
if (child != null) {
mContextMenuInfo = createContextMenuInfo(child, position, id);
if (useOffsets) {
return super.showContextMenuForChild(this, x, y);
} else {
return super.showContextMenuForChild(this);
}
}
}
if (useOffsets) {
return super.showContextMenu(x, y);
} else {
return super.showContextMenu();
}
}
@Override
public boolean showContextMenuForChild(View originalView) {
if (isShowingContextMenuWithCoords()) {
return false;
}
return showContextMenuForChildInternal(originalView, 0, 0, false);
}
@Override
public boolean showContextMenuForChild(View originalView, float x, float y) {
return showContextMenuForChildInternal(originalView,x, y, true);
}
private boolean showContextMenuForChildInternal(View originalView, float x, float y,
boolean useOffsets) {
final int longPressPosition = getPositionForView(originalView);
if (longPressPosition < 0) {
return false;
}
final long longPressId = mAdapter.getItemId(longPressPosition);
boolean handled = false;
if (mOnItemLongClickListener != null) {
handled = mOnItemLongClickListener.onItemLongClick(this, originalView,
longPressPosition, longPressId);
}
if (!handled) {
final View child = getChildAt(longPressPosition - mFirstPosition);
mContextMenuInfo = createContextMenuInfo(child, longPressPosition, longPressId);
if (useOffsets) {
handled = super.showContextMenuForChild(originalView, x, y);
} else {
handled = super.showContextMenuForChild(originalView);
}
}
return handled;
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
return false;
}
@Override
public boolean onKeyUp(int keyCode, KeyEvent event) {
if (KeyEvent.isConfirmKey(keyCode)) {
if (!isEnabled()) {
return true;
}
if (isClickable() && isPressed() &&
mSelectedPosition >= 0 && mAdapter != null &&
mSelectedPosition < mAdapter.getCount()) {
final View view = getChildAt(mSelectedPosition - mFirstPosition);
if (view != null) {
performItemClick(view, mSelectedPosition, mSelectedRowId);
view.setPressed(false);
}
setPressed(false);
return true;
}
}
return super.onKeyUp(keyCode, event);
}
@Override
protected void dispatchSetPressed(boolean pressed) {
// Don't dispatch setPressed to our children. We call setPressed on ourselves to
// get the selector in the right state, but we don't want to press each child.
}
@Override
public void dispatchDrawableHotspotChanged(float x, float y) {
// Don't dispatch hotspot changes to children. We'll manually handle
// calling drawableHotspotChanged on the correct child.
}
/**
* Maps a point to a position in the list.
*
* @param x X in local coordinate
* @param y Y in local coordinate
* @return The position of the item which contains the specified point, or
* {@link #INVALID_POSITION} if the point does not intersect an item.
*/
public int pointToPosition(int x, int y) {
Rect frame = mTouchFrame;
if (frame == null) {
mTouchFrame = new Rect();
frame = mTouchFrame;
}
final int count = getChildCount();
for (int i = count - 1; i >= 0; i--) {
final View child = getChildAt(i);
if (child.getVisibility() == View.VISIBLE) {
child.getHitRect(frame);
if (frame.contains(x, y)) {
return mFirstPosition + i;
}
}
}
return INVALID_POSITION;
}
/**
* Maps a point to a the rowId of the item which intersects that point.
*
* @param x X in local coordinate
* @param y Y in local coordinate
* @return The rowId of the item which contains the specified point, or {@link #INVALID_ROW_ID}
* if the point does not intersect an item.
*/
public long pointToRowId(int x, int y) {
int position = pointToPosition(x, y);
if (position >= 0) {
return mAdapter.getItemId(position);
}
return INVALID_ROW_ID;
}
private final class CheckForTap implements Runnable {
float x;
float y;
@Override
public void run() {
if (mTouchMode == TOUCH_MODE_DOWN) {
mTouchMode = TOUCH_MODE_TAP;
final View child = getChildAt(mMotionPosition - mFirstPosition);
if (child != null && !child.hasExplicitFocusable()) {
mLayoutMode = LAYOUT_NORMAL;
if (!mDataChanged) {
final float[] point = mTmpPoint;
point[0] = x;
point[1] = y;
transformPointToViewLocal(point, child);
child.drawableHotspotChanged(point[0], point[1]);
child.setPressed(true);
setPressed(true);
layoutChildren();
positionSelector(mMotionPosition, child);
refreshDrawableState();
final int longPressTimeout = ViewConfiguration.getLongPressTimeout();
final boolean longClickable = isLongClickable();
if (mSelector != null) {
final Drawable d = mSelector.getCurrent();
if (d != null && d instanceof TransitionDrawable) {
if (longClickable) {
((TransitionDrawable) d).startTransition(longPressTimeout);
} else {
((TransitionDrawable) d).resetTransition();
}
}
mSelector.setHotspot(x, y);
}
if (longClickable) {
if (mPendingCheckForLongPress == null) {
mPendingCheckForLongPress = new CheckForLongPress();
}
mPendingCheckForLongPress.setCoords(x, y);
mPendingCheckForLongPress.rememberWindowAttachCount();
postDelayed(mPendingCheckForLongPress, longPressTimeout);
} else {
mTouchMode = TOUCH_MODE_DONE_WAITING;
}
} else {
mTouchMode = TOUCH_MODE_DONE_WAITING;
}
}
}
}
}
private boolean startScrollIfNeeded(int x, int y, MotionEvent vtev) {
// Check if we have moved far enough that it looks more like a
// scroll than a tap
final int deltaY = y - mMotionY;
final int distance = Math.abs(deltaY);
final boolean overscroll = mScrollY != 0;
if ((overscroll || distance > mTouchSlop) &&
(getNestedScrollAxes() & SCROLL_AXIS_VERTICAL) == 0) {
createScrollingCache();
if (overscroll) {
mTouchMode = TOUCH_MODE_OVERSCROLL;
mMotionCorrection = 0;
} else {
mTouchMode = TOUCH_MODE_SCROLL;
mMotionCorrection = deltaY > 0 ? mTouchSlop : -mTouchSlop;
}
removeCallbacks(mPendingCheckForLongPress);
setPressed(false);
final View motionView = getChildAt(mMotionPosition - mFirstPosition);
if (motionView != null) {
motionView.setPressed(false);
}
reportScrollStateChange(OnScrollListener.SCROLL_STATE_TOUCH_SCROLL);
// Time to start stealing events! Once we've stolen them, don't let anyone
// steal from us
final ViewParent parent = getParent();
if (parent != null) {
parent.requestDisallowInterceptTouchEvent(true);
}
scrollIfNeeded(x, y, vtev);
return true;
}
return false;
}
private void scrollIfNeeded(int x, int y, MotionEvent vtev) {
int rawDeltaY = y - mMotionY;
int scrollOffsetCorrection = 0;
if (mLastY == Integer.MIN_VALUE) {
rawDeltaY -= mMotionCorrection;
}
int incrementalDeltaY = mLastY != Integer.MIN_VALUE ? y - mLastY : rawDeltaY;
// First allow releasing existing overscroll effect:
incrementalDeltaY = releaseGlow(incrementalDeltaY, x);
if (dispatchNestedPreScroll(0, -incrementalDeltaY, mScrollConsumed, mScrollOffset)) {
rawDeltaY += mScrollConsumed[1];
scrollOffsetCorrection = -mScrollOffset[1];
incrementalDeltaY += mScrollConsumed[1];
if (vtev != null) {
vtev.offsetLocation(0, mScrollOffset[1]);
mNestedYOffset += mScrollOffset[1];
}
}
final int deltaY = rawDeltaY;
int lastYCorrection = 0;
if (mTouchMode == TOUCH_MODE_SCROLL) {
if (PROFILE_SCROLLING) {
if (!mScrollProfilingStarted) {
Debug.startMethodTracing("AbsListViewScroll");
mScrollProfilingStarted = true;
}
}
if (mScrollStrictSpan == null) {
// If it's non-null, we're already in a scroll.
mScrollStrictSpan = StrictMode.enterCriticalSpan("AbsListView-scroll");
}
if (y != mLastY) {
// We may be here after stopping a fling and continuing to scroll.
// If so, we haven't disallowed intercepting touch events yet.
// Make sure that we do so in case we're in a parent that can intercept.
if ((mGroupFlags & FLAG_DISALLOW_INTERCEPT) == 0 &&
Math.abs(rawDeltaY) > mTouchSlop) {
final ViewParent parent = getParent();
if (parent != null) {
parent.requestDisallowInterceptTouchEvent(true);
}
}
final int motionIndex;
if (mMotionPosition >= 0) {
motionIndex = mMotionPosition - mFirstPosition;
} else {
// If we don't have a motion position that we can reliably track,
// pick something in the middle to make a best guess at things below.
motionIndex = getChildCount() / 2;
}
int motionViewPrevTop = 0;
View motionView = this.getChildAt(motionIndex);
if (motionView != null) {
motionViewPrevTop = motionView.getTop();
}
// No need to do all this work if we're not going to move anyway
boolean atEdge = false;
if (incrementalDeltaY != 0) {
atEdge = trackMotionScroll(deltaY, incrementalDeltaY);
}
// Check to see if we have bumped into the scroll limit
motionView = this.getChildAt(motionIndex);
if (motionView != null) {
// Check if the top of the motion view is where it is
// supposed to be
final int motionViewRealTop = motionView.getTop();
if (atEdge) {
// Apply overscroll
int overscroll = -incrementalDeltaY -
(motionViewRealTop - motionViewPrevTop);
if (dispatchNestedScroll(0, overscroll - incrementalDeltaY, 0, overscroll,
mScrollOffset)) {
lastYCorrection -= mScrollOffset[1];
if (vtev != null) {
vtev.offsetLocation(0, mScrollOffset[1]);
mNestedYOffset += mScrollOffset[1];
}
} else {
final boolean atOverscrollEdge = overScrollBy(0, overscroll,
0, mScrollY, 0, 0, 0, mOverscrollDistance, true);
if (atOverscrollEdge && mVelocityTracker != null) {
// Don't allow overfling if we're at the edge
mVelocityTracker.clear();
}
final int overscrollMode = getOverScrollMode();
if (overscrollMode == OVER_SCROLL_ALWAYS ||
(overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS &&
!contentFits())) {
if (!atOverscrollEdge) {
mDirection = 0; // Reset when entering overscroll.
mTouchMode = TOUCH_MODE_OVERSCROLL;
}
if (incrementalDeltaY > 0) {
mEdgeGlowTop.onPullDistance((float) -overscroll / getHeight(),
(float) x / getWidth());
if (!mEdgeGlowBottom.isFinished()) {
mEdgeGlowBottom.onRelease();
}
invalidateEdgeEffects();
} else if (incrementalDeltaY < 0) {
mEdgeGlowBottom.onPullDistance((float) overscroll / getHeight(),
1.f - (float) x / getWidth());
if (!mEdgeGlowTop.isFinished()) {
mEdgeGlowTop.onRelease();
}
invalidateEdgeEffects();
}
}
}
}
mMotionY = y + lastYCorrection + scrollOffsetCorrection;
}
mLastY = y + lastYCorrection + scrollOffsetCorrection;
}
} else if (mTouchMode == TOUCH_MODE_OVERSCROLL) {
if (y != mLastY) {
final int oldScroll = mScrollY;
final int newScroll = oldScroll - incrementalDeltaY;
int newDirection = y > mLastY ? 1 : -1;
if (mDirection == 0) {
mDirection = newDirection;
}
int overScrollDistance = -incrementalDeltaY;
if ((newScroll < 0 && oldScroll >= 0) || (newScroll > 0 && oldScroll <= 0)) {
overScrollDistance = -oldScroll;
incrementalDeltaY += overScrollDistance;
} else {
incrementalDeltaY = 0;
}
if (overScrollDistance != 0) {
overScrollBy(0, overScrollDistance, 0, mScrollY, 0, 0,
0, mOverscrollDistance, true);
final int overscrollMode = getOverScrollMode();
if (overscrollMode == OVER_SCROLL_ALWAYS ||
(overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS &&
!contentFits())) {
if (rawDeltaY > 0) {
mEdgeGlowTop.onPullDistance((float) overScrollDistance / getHeight(),
(float) x / getWidth());
if (!mEdgeGlowBottom.isFinished()) {
mEdgeGlowBottom.onRelease();
}
invalidateEdgeEffects();
} else if (rawDeltaY < 0) {
mEdgeGlowBottom.onPullDistance(
(float) -overScrollDistance / getHeight(),
1.f - (float) x / getWidth());
if (!mEdgeGlowTop.isFinished()) {
mEdgeGlowTop.onRelease();
}
invalidateEdgeEffects();
}
}
}
if (incrementalDeltaY != 0) {
// Coming back to 'real' list scrolling
if (mScrollY != 0) {
mScrollY = 0;
invalidateParentIfNeeded();
}
trackMotionScroll(incrementalDeltaY, incrementalDeltaY);
mTouchMode = TOUCH_MODE_SCROLL;
// We did not scroll the full amount. Treat this essentially like the
// start of a new touch scroll
final int motionPosition = findClosestMotionRow(y);
mMotionCorrection = 0;
View motionView = getChildAt(motionPosition - mFirstPosition);
mMotionViewOriginalTop = motionView != null ? motionView.getTop() : 0;
mMotionY = y + scrollOffsetCorrection;
mMotionPosition = motionPosition;
}
mLastY = y + lastYCorrection + scrollOffsetCorrection;
mDirection = newDirection;
}
}
}
/**
* If the edge glow is currently active, this consumes part or all of deltaY
* on the edge glow.
*
* @param deltaY The pointer motion, in pixels, in the vertical direction, positive
* for moving down and negative for moving up.
* @param x The horizontal position of the pointer.
* @return The remainder of deltaY
that has not been consumed by the
* edge glow.
*/
private int releaseGlow(int deltaY, int x) {
// First allow releasing existing overscroll effect:
float consumed = 0;
if (mEdgeGlowTop.getDistance() != 0) {
if (canScrollUp()) {
mEdgeGlowTop.onRelease();
} else {
consumed = mEdgeGlowTop.onPullDistance((float) deltaY / getHeight(),
(float) x / getWidth());
}
invalidateEdgeEffects();
} else if (mEdgeGlowBottom.getDistance() != 0) {
if (canScrollDown()) {
mEdgeGlowBottom.onRelease();
} else {
consumed = -mEdgeGlowBottom.onPullDistance((float) -deltaY / getHeight(),
1f - (float) x / getWidth());
}
invalidateEdgeEffects();
}
int pixelsConsumed = Math.round(consumed * getHeight());
return deltaY - pixelsConsumed;
}
/**
* @return true
if either the top or bottom edge glow is currently active or
* false
if it has no value to release.
*/
private boolean doesTouchStopStretch() {
return (mEdgeGlowBottom.getDistance() != 0 && !canScrollDown())
|| (mEdgeGlowTop.getDistance() != 0 && !canScrollUp());
}
private void invalidateEdgeEffects() {
if (!shouldDisplayEdgeEffects()) {
return;
}
invalidate();
}
@Override
public void onTouchModeChanged(boolean isInTouchMode) {
if (isInTouchMode) {
// Get rid of the selection when we enter touch mode
hideSelector();
// Layout, but only if we already have done so previously.
// (Otherwise may clobber a LAYOUT_SYNC layout that was requested to restore
// state.)
if (getHeight() > 0 && getChildCount() > 0) {
// We do not lose focus initiating a touch (since AbsListView is focusable in
// touch mode). Force an initial layout to get rid of the selection.
layoutChildren();
}
updateSelectorState();
} else {
int touchMode = mTouchMode;
if (touchMode == TOUCH_MODE_OVERSCROLL || touchMode == TOUCH_MODE_OVERFLING) {
if (mFlingRunnable != null) {
mFlingRunnable.endFling();
}
if (mPositionScroller != null) {
mPositionScroller.stop();
}
if (mScrollY != 0) {
mScrollY = 0;
invalidateParentCaches();
finishGlows();
invalidate();
}
}
}
}
/** @hide */
@Override
protected boolean handleScrollBarDragging(MotionEvent event) {
// Doesn't support normal scroll bar dragging. Use FastScroller.
return false;
}
@Override
public boolean onTouchEvent(MotionEvent ev) {
if (!isEnabled()) {
// A disabled view that is clickable still consumes the touch
// events, it just doesn't respond to them.
return isClickable() || isLongClickable();
}
if (mPositionScroller != null) {
mPositionScroller.stop();
}
if (mIsDetaching || !isAttachedToWindow()) {
// Something isn't right.
// Since we rely on being attached to get data set change notifications,
// don't risk doing anything where we might try to resync and find things
// in a bogus state.
return false;
}
startNestedScroll(SCROLL_AXIS_VERTICAL);
if (mFastScroll != null && mFastScroll.onTouchEvent(ev)) {
return true;
}
initVelocityTrackerIfNotExists();
final MotionEvent vtev = MotionEvent.obtain(ev);
final int actionMasked = ev.getActionMasked();
if (actionMasked == MotionEvent.ACTION_DOWN) {
mNestedYOffset = 0;
}
vtev.offsetLocation(0, mNestedYOffset);
switch (actionMasked) {
case MotionEvent.ACTION_DOWN: {
onTouchDown(ev);
break;
}
case MotionEvent.ACTION_MOVE: {
onTouchMove(ev, vtev);
break;
}
case MotionEvent.ACTION_UP: {
onTouchUp(ev);
break;
}
case MotionEvent.ACTION_CANCEL: {
onTouchCancel();
break;
}
case MotionEvent.ACTION_POINTER_UP: {
onSecondaryPointerUp(ev);
final int x = mMotionX;
final int y = mMotionY;
final int motionPosition = pointToPosition(x, y);
if (motionPosition >= 0) {
// Remember where the motion event started
final View child = getChildAt(motionPosition - mFirstPosition);
mMotionViewOriginalTop = child.getTop();
mMotionPosition = motionPosition;
}
mLastY = y;
break;
}
case MotionEvent.ACTION_POINTER_DOWN: {
// New pointers take over dragging duties
final int index = ev.getActionIndex();
final int id = ev.getPointerId(index);
final int x = (int) ev.getX(index);
final int y = (int) ev.getY(index);
mMotionCorrection = 0;
mActivePointerId = id;
mMotionX = x;
mMotionY = y;
final int motionPosition = pointToPosition(x, y);
if (motionPosition >= 0) {
// Remember where the motion event started
final View child = getChildAt(motionPosition - mFirstPosition);
mMotionViewOriginalTop = child.getTop();
mMotionPosition = motionPosition;
}
mLastY = y;
break;
}
}
if (mVelocityTracker != null) {
mVelocityTracker.addMovement(vtev);
}
vtev.recycle();
return true;
}
private void onTouchDown(MotionEvent ev) {
mHasPerformedLongPress = false;
mActivePointerId = ev.getPointerId(0);
hideSelector();
if (mTouchMode == TOUCH_MODE_OVERFLING) {
// Stopped the fling. It is a scroll.
if (mFlingRunnable != null) {
mFlingRunnable.endFling();
}
if (mPositionScroller != null) {
mPositionScroller.stop();
}
mTouchMode = TOUCH_MODE_OVERSCROLL;
mMotionX = (int) ev.getX();
mMotionY = (int) ev.getY();
mLastY = mMotionY;
mMotionCorrection = 0;
mDirection = 0;
stopEdgeGlowRecede(ev.getX());
} else {
final int x = (int) ev.getX();
final int y = (int) ev.getY();
int motionPosition = pointToPosition(x, y);
if (!mDataChanged) {
if (mTouchMode == TOUCH_MODE_FLING) {
// Stopped a fling. It is a scroll.
createScrollingCache();
mTouchMode = TOUCH_MODE_SCROLL;
mMotionCorrection = 0;
motionPosition = findMotionRow(y);
if (mFlingRunnable != null) {
mFlingRunnable.flywheelTouch();
}
stopEdgeGlowRecede(x);
} else if ((motionPosition >= 0) && getAdapter().isEnabled(motionPosition)) {
// User clicked on an actual view (and was not stopping a
// fling). It might be a click or a scroll. Assume it is a
// click until proven otherwise.
mTouchMode = TOUCH_MODE_DOWN;
// FIXME Debounce
if (mPendingCheckForTap == null) {
mPendingCheckForTap = new CheckForTap();
}
mPendingCheckForTap.x = ev.getX();
mPendingCheckForTap.y = ev.getY();
postDelayed(mPendingCheckForTap, ViewConfiguration.getTapTimeout());
}
}
if (motionPosition >= 0) {
// Remember where the motion event started
final View v = getChildAt(motionPosition - mFirstPosition);
mMotionViewOriginalTop = v.getTop();
}
mMotionX = x;
mMotionY = y;
mMotionPosition = motionPosition;
mLastY = Integer.MIN_VALUE;
}
if (mTouchMode == TOUCH_MODE_DOWN && mMotionPosition != INVALID_POSITION
&& performButtonActionOnTouchDown(ev)) {
removeCallbacks(mPendingCheckForTap);
}
}
private void stopEdgeGlowRecede(float x) {
if (mEdgeGlowTop.getDistance() != 0) {
mEdgeGlowTop.onPullDistance(0, x / getWidth());
}
if (mEdgeGlowBottom.getDistance() != 0) {
mEdgeGlowBottom.onPullDistance(0, x / getWidth());
}
}
private void onTouchMove(MotionEvent ev, MotionEvent vtev) {
if (mHasPerformedLongPress) {
// Consume all move events following a successful long press.
return;
}
int pointerIndex = ev.findPointerIndex(mActivePointerId);
if (pointerIndex == -1) {
pointerIndex = 0;
mActivePointerId = ev.getPointerId(pointerIndex);
}
if (mDataChanged) {
// Re-sync everything if data has been changed
// since the scroll operation can query the adapter.
layoutChildren();
}
final int y = (int) ev.getY(pointerIndex);
switch (mTouchMode) {
case TOUCH_MODE_DOWN:
case TOUCH_MODE_TAP:
case TOUCH_MODE_DONE_WAITING:
// Check if we have moved far enough that it looks more like a
// scroll than a tap. If so, we'll enter scrolling mode.
if (startScrollIfNeeded((int) ev.getX(pointerIndex), y, vtev)) {
break;
}
// Otherwise, check containment within list bounds. If we're
// outside bounds, cancel any active presses.
final View motionView = getChildAt(mMotionPosition - mFirstPosition);
final float x = ev.getX(pointerIndex);
if (!pointInView(x, y, mTouchSlop)) {
setPressed(false);
if (motionView != null) {
motionView.setPressed(false);
}
removeCallbacks(mTouchMode == TOUCH_MODE_DOWN ?
mPendingCheckForTap : mPendingCheckForLongPress);
mTouchMode = TOUCH_MODE_DONE_WAITING;
updateSelectorState();
} else if (motionView != null) {
// Still within bounds, update the hotspot.
final float[] point = mTmpPoint;
point[0] = x;
point[1] = y;
transformPointToViewLocal(point, motionView);
motionView.drawableHotspotChanged(point[0], point[1]);
}
break;
case TOUCH_MODE_SCROLL:
case TOUCH_MODE_OVERSCROLL:
scrollIfNeeded((int) ev.getX(pointerIndex), y, vtev);
break;
}
}
private void onTouchUp(MotionEvent ev) {
switch (mTouchMode) {
case TOUCH_MODE_DOWN:
case TOUCH_MODE_TAP:
case TOUCH_MODE_DONE_WAITING:
final int motionPosition = mMotionPosition;
final View child = getChildAt(motionPosition - mFirstPosition);
if (child != null) {
if (mTouchMode != TOUCH_MODE_DOWN) {
child.setPressed(false);
}
final float x = ev.getX();
final boolean inList =
x > mListPadding.left && x < getWidth() - mListPadding.right;
if (inList && !child.hasExplicitFocusable()) {
if (mPerformClick == null) {
mPerformClick = new PerformClick();
}
final AbsListView.PerformClick performClick = mPerformClick;
performClick.mClickMotionPosition = motionPosition;
performClick.rememberWindowAttachCount();
mResurrectToPosition = motionPosition;
if (mTouchMode == TOUCH_MODE_DOWN || mTouchMode == TOUCH_MODE_TAP) {
removeCallbacks(mTouchMode == TOUCH_MODE_DOWN
? mPendingCheckForTap : mPendingCheckForLongPress);
mLayoutMode = LAYOUT_NORMAL;
if (!mDataChanged && mAdapter.isEnabled(motionPosition)) {
mTouchMode = TOUCH_MODE_TAP;
setSelectedPositionInt(mMotionPosition);
layoutChildren();
child.setPressed(true);
positionSelector(mMotionPosition, child);
setPressed(true);
if (mSelector != null) {
Drawable d = mSelector.getCurrent();
if (d != null && d instanceof TransitionDrawable) {
((TransitionDrawable) d).resetTransition();
}
mSelector.setHotspot(x, ev.getY());
}
if (mTouchModeReset != null) {
removeCallbacks(mTouchModeReset);
}
mTouchModeReset = new Runnable() {
@Override
public void run() {
mTouchModeReset = null;
mTouchMode = TOUCH_MODE_REST;
child.setPressed(false);
setPressed(false);
if (!mDataChanged && !mIsDetaching
&& isAttachedToWindow()) {
performClick.run();
}
}
};
postDelayed(mTouchModeReset,
ViewConfiguration.getPressedStateDuration());
} else {
mTouchMode = TOUCH_MODE_REST;
updateSelectorState();
}
return;
} else if (!mDataChanged && mAdapter.isEnabled(motionPosition)) {
performClick.run();
}
}
}
mTouchMode = TOUCH_MODE_REST;
updateSelectorState();
break;
case TOUCH_MODE_SCROLL:
final int childCount = getChildCount();
if (childCount > 0) {
final int firstChildTop = getChildAt(0).getTop();
final int lastChildBottom = getChildAt(childCount - 1).getBottom();
final int contentTop = mListPadding.top;
final int contentBottom = getHeight() - mListPadding.bottom;
if (mFirstPosition == 0 && firstChildTop >= contentTop
&& mFirstPosition + childCount < mItemCount
&& lastChildBottom <= getHeight() - contentBottom) {
mTouchMode = TOUCH_MODE_REST;
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
} else {
final VelocityTracker velocityTracker = mVelocityTracker;
velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
final int initialVelocity = (int)
(velocityTracker.getYVelocity(mActivePointerId) * mVelocityScale);
// Fling if we have enough velocity and we aren't at a boundary.
// Since we can potentially overfling more than we can overscroll, don't
// allow the weird behavior where you can scroll to a boundary then
// fling further.
boolean flingVelocity = Math.abs(initialVelocity) > mMinimumVelocity;
if (flingVelocity && !mEdgeGlowTop.isFinished()) {
mEdgeGlowTop.onAbsorb(initialVelocity);
} else if (flingVelocity && !mEdgeGlowBottom.isFinished()) {
mEdgeGlowBottom.onAbsorb(-initialVelocity);
} else if (flingVelocity
&& !((mFirstPosition == 0
&& firstChildTop == contentTop - mOverscrollDistance)
|| (mFirstPosition + childCount == mItemCount
&& lastChildBottom == contentBottom + mOverscrollDistance))
) {
if (!dispatchNestedPreFling(0, -initialVelocity)) {
if (mFlingRunnable == null) {
mFlingRunnable = new FlingRunnable();
}
reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING);
mFlingRunnable.start(-initialVelocity);
dispatchNestedFling(0, -initialVelocity, true);
} else {
mTouchMode = TOUCH_MODE_REST;
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
}
} else {
mTouchMode = TOUCH_MODE_REST;
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
if (mFlingRunnable != null) {
mFlingRunnable.endFling();
}
if (mPositionScroller != null) {
mPositionScroller.stop();
}
if (flingVelocity && !dispatchNestedPreFling(0, -initialVelocity)) {
dispatchNestedFling(0, -initialVelocity, false);
}
}
}
} else {
mTouchMode = TOUCH_MODE_REST;
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
}
break;
case TOUCH_MODE_OVERSCROLL:
if (mFlingRunnable == null) {
mFlingRunnable = new FlingRunnable();
}
final VelocityTracker velocityTracker = mVelocityTracker;
velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
final int initialVelocity = (int) velocityTracker.getYVelocity(mActivePointerId);
reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING);
if (Math.abs(initialVelocity) > mMinimumVelocity) {
mFlingRunnable.startOverfling(-initialVelocity);
} else {
mFlingRunnable.startSpringback();
}
break;
}
setPressed(false);
if (shouldDisplayEdgeEffects()) {
mEdgeGlowTop.onRelease();
mEdgeGlowBottom.onRelease();
}
// Need to redraw since we probably aren't drawing the selector anymore
invalidate();
removeCallbacks(mPendingCheckForLongPress);
recycleVelocityTracker();
mActivePointerId = INVALID_POINTER;
if (PROFILE_SCROLLING) {
if (mScrollProfilingStarted) {
Debug.stopMethodTracing();
mScrollProfilingStarted = false;
}
}
if (mScrollStrictSpan != null) {
mScrollStrictSpan.finish();
mScrollStrictSpan = null;
}
}
private boolean shouldDisplayEdgeEffects() {
return getOverScrollMode() != OVER_SCROLL_NEVER;
}
private void onTouchCancel() {
switch (mTouchMode) {
case TOUCH_MODE_OVERSCROLL:
if (mFlingRunnable == null) {
mFlingRunnable = new FlingRunnable();
}
mFlingRunnable.startSpringback();
break;
case TOUCH_MODE_OVERFLING:
// Do nothing - let it play out.
break;
default:
mTouchMode = TOUCH_MODE_REST;
setPressed(false);
final View motionView = this.getChildAt(mMotionPosition - mFirstPosition);
if (motionView != null) {
motionView.setPressed(false);
}
clearScrollingCache();
removeCallbacks(mPendingCheckForLongPress);
recycleVelocityTracker();
}
if (shouldDisplayEdgeEffects()) {
mEdgeGlowTop.onRelease();
mEdgeGlowBottom.onRelease();
}
mActivePointerId = INVALID_POINTER;
}
@Override
protected void onOverScrolled(int scrollX, int scrollY, boolean clampedX, boolean clampedY) {
if (mScrollY != scrollY) {
onScrollChanged(mScrollX, scrollY, mScrollX, mScrollY);
mScrollY = scrollY;
invalidateParentIfNeeded();
awakenScrollBars();
}
}
@Override
public boolean onGenericMotionEvent(MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_SCROLL:
final float axisValue;
if (event.isFromSource(InputDevice.SOURCE_CLASS_POINTER)) {
axisValue = event.getAxisValue(MotionEvent.AXIS_VSCROLL);
} else if (event.isFromSource(InputDevice.SOURCE_ROTARY_ENCODER)) {
axisValue = event.getAxisValue(MotionEvent.AXIS_SCROLL);
} else {
axisValue = 0;
}
final int delta = Math.round(axisValue * mVerticalScrollFactor);
if (delta != 0) {
if (!trackMotionScroll(delta, delta)) {
return true;
}
}
break;
case MotionEvent.ACTION_BUTTON_PRESS:
if (event.isFromSource(InputDevice.SOURCE_CLASS_POINTER)) {
int actionButton = event.getActionButton();
if ((actionButton == MotionEvent.BUTTON_STYLUS_PRIMARY
|| actionButton == MotionEvent.BUTTON_SECONDARY)
&& (mTouchMode == TOUCH_MODE_DOWN || mTouchMode == TOUCH_MODE_TAP)) {
if (performStylusButtonPressAction(event)) {
removeCallbacks(mPendingCheckForLongPress);
removeCallbacks(mPendingCheckForTap);
}
}
}
break;
}
return super.onGenericMotionEvent(event);
}
/**
* Initiate a fling with the given velocity.
*
*
Applications can use this method to manually initiate a fling as if the user
* initiated it via touch interaction.
*
* @param velocityY Vertical velocity in pixels per second. Note that this is velocity of
* content, not velocity of a touch that initiated the fling.
*/
public void fling(int velocityY) {
if (mFlingRunnable == null) {
mFlingRunnable = new FlingRunnable();
}
reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING);
mFlingRunnable.start(velocityY);
}
@Override
public boolean onStartNestedScroll(View child, View target, int nestedScrollAxes) {
return ((nestedScrollAxes & SCROLL_AXIS_VERTICAL) != 0);
}
@Override
public void onNestedScrollAccepted(View child, View target, int axes) {
super.onNestedScrollAccepted(child, target, axes);
startNestedScroll(SCROLL_AXIS_VERTICAL);
}
@Override
public void onNestedScroll(View target, int dxConsumed, int dyConsumed,
int dxUnconsumed, int dyUnconsumed) {
final int motionIndex = getChildCount() / 2;
final View motionView = getChildAt(motionIndex);
final int oldTop = motionView != null ? motionView.getTop() : 0;
if (motionView == null || trackMotionScroll(-dyUnconsumed, -dyUnconsumed)) {
int myUnconsumed = dyUnconsumed;
int myConsumed = 0;
if (motionView != null) {
myConsumed = motionView.getTop() - oldTop;
myUnconsumed -= myConsumed;
}
dispatchNestedScroll(0, myConsumed, 0, myUnconsumed, null);
}
}
@Override
public boolean onNestedFling(View target, float velocityX, float velocityY, boolean consumed) {
final int childCount = getChildCount();
if (!consumed && childCount > 0 && canScrollList((int) velocityY) &&
Math.abs(velocityY) > mMinimumVelocity) {
reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING);
if (mFlingRunnable == null) {
mFlingRunnable = new FlingRunnable();
}
if (!dispatchNestedPreFling(0, velocityY)) {
mFlingRunnable.start((int) velocityY);
}
return true;
}
return dispatchNestedFling(velocityX, velocityY, consumed);
}
@Override
public void draw(Canvas canvas) {
super.draw(canvas);
if (shouldDisplayEdgeEffects()) {
final int scrollY = mScrollY;
final boolean clipToPadding = getClipToPadding();
final int width;
final int height;
final int translateX;
final int translateY;
if (clipToPadding) {
width = getWidth() - mPaddingLeft - mPaddingRight;
height = getHeight() - mPaddingTop - mPaddingBottom;
translateX = mPaddingLeft;
translateY = mPaddingTop;
} else {
width = getWidth();
height = getHeight();
translateX = 0;
translateY = 0;
}
mEdgeGlowTop.setSize(width, height);
mEdgeGlowBottom.setSize(width, height);
if (!mEdgeGlowTop.isFinished()) {
final int restoreCount = canvas.save();
canvas.clipRect(translateX, translateY,
translateX + width ,translateY + mEdgeGlowTop.getMaxHeight());
final int edgeY = Math.min(0, scrollY + mFirstPositionDistanceGuess) + translateY;
canvas.translate(translateX, edgeY);
if (mEdgeGlowTop.draw(canvas)) {
invalidateEdgeEffects();
}
canvas.restoreToCount(restoreCount);
}
if (!mEdgeGlowBottom.isFinished()) {
final int restoreCount = canvas.save();
canvas.clipRect(translateX, translateY + height - mEdgeGlowBottom.getMaxHeight(),
translateX + width, translateY + height);
final int edgeX = -width + translateX;
final int edgeY = Math.max(getHeight(), scrollY + mLastPositionDistanceGuess)
- (clipToPadding ? mPaddingBottom : 0);
canvas.translate(edgeX, edgeY);
canvas.rotate(180, width, 0);
if (mEdgeGlowBottom.draw(canvas)) {
invalidateEdgeEffects();
}
canvas.restoreToCount(restoreCount);
}
}
}
private void initOrResetVelocityTracker() {
if (mVelocityTracker == null) {
mVelocityTracker = VelocityTracker.obtain();
} else {
mVelocityTracker.clear();
}
}
private void initVelocityTrackerIfNotExists() {
if (mVelocityTracker == null) {
mVelocityTracker = VelocityTracker.obtain();
}
}
private void recycleVelocityTracker() {
if (mVelocityTracker != null) {
mVelocityTracker.recycle();
mVelocityTracker = null;
}
}
@Override
public void requestDisallowInterceptTouchEvent(boolean disallowIntercept) {
if (disallowIntercept) {
recycleVelocityTracker();
}
super.requestDisallowInterceptTouchEvent(disallowIntercept);
}
@Override
public boolean onInterceptHoverEvent(MotionEvent event) {
if (mFastScroll != null && mFastScroll.onInterceptHoverEvent(event)) {
return true;
}
return super.onInterceptHoverEvent(event);
}
@Override
public PointerIcon onResolvePointerIcon(MotionEvent event, int pointerIndex) {
if (mFastScroll != null) {
PointerIcon pointerIcon = mFastScroll.onResolvePointerIcon(event, pointerIndex);
if (pointerIcon != null) {
return pointerIcon;
}
}
return super.onResolvePointerIcon(event, pointerIndex);
}
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
final int actionMasked = ev.getActionMasked();
View v;
if (mPositionScroller != null) {
mPositionScroller.stop();
}
if (mIsDetaching || !isAttachedToWindow()) {
// Something isn't right.
// Since we rely on being attached to get data set change notifications,
// don't risk doing anything where we might try to resync and find things
// in a bogus state.
return false;
}
if (mFastScroll != null && mFastScroll.onInterceptTouchEvent(ev)) {
return true;
}
switch (actionMasked) {
case MotionEvent.ACTION_DOWN: {
int touchMode = mTouchMode;
if (touchMode == TOUCH_MODE_OVERFLING || touchMode == TOUCH_MODE_OVERSCROLL) {
mMotionCorrection = 0;
return true;
}
final int x = (int) ev.getX();
final int y = (int) ev.getY();
mActivePointerId = ev.getPointerId(0);
int motionPosition = findMotionRow(y);
if (doesTouchStopStretch()) {
// Pressed during edge effect, so this is considered the same as a fling catch.
touchMode = mTouchMode = TOUCH_MODE_FLING;
} else if (touchMode != TOUCH_MODE_FLING && motionPosition >= 0) {
// User clicked on an actual view (and was not stopping a fling).
// Remember where the motion event started
v = getChildAt(motionPosition - mFirstPosition);
mMotionViewOriginalTop = v.getTop();
mMotionX = x;
mMotionY = y;
mMotionPosition = motionPosition;
mTouchMode = TOUCH_MODE_DOWN;
clearScrollingCache();
}
mLastY = Integer.MIN_VALUE;
initOrResetVelocityTracker();
mVelocityTracker.addMovement(ev);
mNestedYOffset = 0;
startNestedScroll(SCROLL_AXIS_VERTICAL);
if (touchMode == TOUCH_MODE_FLING) {
return true;
}
break;
}
case MotionEvent.ACTION_MOVE: {
switch (mTouchMode) {
case TOUCH_MODE_DOWN:
int pointerIndex = ev.findPointerIndex(mActivePointerId);
if (pointerIndex == -1) {
pointerIndex = 0;
mActivePointerId = ev.getPointerId(pointerIndex);
}
final int y = (int) ev.getY(pointerIndex);
initVelocityTrackerIfNotExists();
mVelocityTracker.addMovement(ev);
if (startScrollIfNeeded((int) ev.getX(pointerIndex), y, null)) {
return true;
}
break;
}
break;
}
case MotionEvent.ACTION_CANCEL:
case MotionEvent.ACTION_UP: {
mTouchMode = TOUCH_MODE_REST;
mActivePointerId = INVALID_POINTER;
recycleVelocityTracker();
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
stopNestedScroll();
break;
}
case MotionEvent.ACTION_POINTER_UP: {
onSecondaryPointerUp(ev);
break;
}
}
return false;
}
private void onSecondaryPointerUp(MotionEvent ev) {
final int pointerIndex = (ev.getAction() & MotionEvent.ACTION_POINTER_INDEX_MASK) >>
MotionEvent.ACTION_POINTER_INDEX_SHIFT;
final int pointerId = ev.getPointerId(pointerIndex);
if (pointerId == mActivePointerId) {
// This was our active pointer going up. Choose a new
// active pointer and adjust accordingly.
// TODO: Make this decision more intelligent.
final int newPointerIndex = pointerIndex == 0 ? 1 : 0;
mMotionX = (int) ev.getX(newPointerIndex);
mMotionY = (int) ev.getY(newPointerIndex);
mMotionCorrection = 0;
mActivePointerId = ev.getPointerId(newPointerIndex);
}
}
/**
* {@inheritDoc}
*/
@Override
public void addTouchables(ArrayList views) {
final int count = getChildCount();
final int firstPosition = mFirstPosition;
final ListAdapter adapter = mAdapter;
if (adapter == null) {
return;
}
for (int i = 0; i < count; i++) {
final View child = getChildAt(i);
if (adapter.isEnabled(firstPosition + i)) {
views.add(child);
}
child.addTouchables(views);
}
}
/**
* Fires an "on scroll state changed" event to the registered
* {@link android.widget.AbsListView.OnScrollListener}, if any. The state change
* is fired only if the specified state is different from the previously known state.
*
* @param newState The new scroll state.
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 123769710)
void reportScrollStateChange(int newState) {
if (newState != mLastScrollState) {
if (mOnScrollListener != null) {
mLastScrollState = newState;
mOnScrollListener.onScrollStateChanged(this, newState);
}
}
}
/**
* Responsible for fling behavior. Use {@link #start(int)} to
* initiate a fling. Each frame of the fling is handled in {@link #run()}.
* A FlingRunnable will keep re-posting itself until the fling is done.
*
*/
private class FlingRunnable implements Runnable {
/**
* Tracks the decay of a fling scroll
*/
@UnsupportedAppUsage
private final OverScroller mScroller;
/**
* Y value reported by mScroller on the previous fling
*/
private int mLastFlingY;
/**
* If true, {@link #endFling()} will not report scroll state change to
* {@link OnScrollListener#SCROLL_STATE_IDLE}.
*/
private boolean mSuppressIdleStateChangeCall;
private final Runnable mCheckFlywheel = new Runnable() {
@Override
public void run() {
final int activeId = mActivePointerId;
final VelocityTracker vt = mVelocityTracker;
final OverScroller scroller = mScroller;
if (vt == null || activeId == INVALID_POINTER) {
return;
}
vt.computeCurrentVelocity(1000, mMaximumVelocity);
final float yvel = -vt.getYVelocity(activeId);
if (Math.abs(yvel) >= mMinimumVelocity
&& scroller.isScrollingInDirection(0, yvel)) {
// Keep the fling alive a little longer
postDelayed(this, FLYWHEEL_TIMEOUT);
} else {
endFling();
mTouchMode = TOUCH_MODE_SCROLL;
reportScrollStateChange(OnScrollListener.SCROLL_STATE_TOUCH_SCROLL);
}
}
};
private static final int FLYWHEEL_TIMEOUT = 40; // milliseconds
FlingRunnable() {
mScroller = new OverScroller(getContext());
}
// Use AbsListView#fling(int) instead
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P)
void start(int initialVelocity) {
int initialY = initialVelocity < 0 ? Integer.MAX_VALUE : 0;
mLastFlingY = initialY;
mScroller.setInterpolator(null);
mScroller.fling(0, initialY, 0, initialVelocity,
0, Integer.MAX_VALUE, 0, Integer.MAX_VALUE);
mTouchMode = TOUCH_MODE_FLING;
mSuppressIdleStateChangeCall = false;
removeCallbacks(this);
postOnAnimation(this);
if (PROFILE_FLINGING) {
if (!mFlingProfilingStarted) {
Debug.startMethodTracing("AbsListViewFling");
mFlingProfilingStarted = true;
}
}
if (mFlingStrictSpan == null) {
mFlingStrictSpan = StrictMode.enterCriticalSpan("AbsListView-fling");
}
}
void startSpringback() {
mSuppressIdleStateChangeCall = false;
if (mScroller.springBack(0, mScrollY, 0, 0, 0, 0)) {
mTouchMode = TOUCH_MODE_OVERFLING;
invalidate();
postOnAnimation(this);
} else {
mTouchMode = TOUCH_MODE_REST;
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
}
}
void startOverfling(int initialVelocity) {
mScroller.setInterpolator(null);
mScroller.fling(0, mScrollY, 0, initialVelocity, 0, 0,
Integer.MIN_VALUE, Integer.MAX_VALUE, 0, getHeight());
mTouchMode = TOUCH_MODE_OVERFLING;
mSuppressIdleStateChangeCall = false;
invalidate();
postOnAnimation(this);
}
void edgeReached(int delta) {
mScroller.notifyVerticalEdgeReached(mScrollY, 0, mOverflingDistance);
final int overscrollMode = getOverScrollMode();
if (overscrollMode == OVER_SCROLL_ALWAYS ||
(overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && !contentFits())) {
mTouchMode = TOUCH_MODE_OVERFLING;
final int vel = (int) mScroller.getCurrVelocity();
if (delta > 0) {
mEdgeGlowTop.onAbsorb(vel);
} else {
mEdgeGlowBottom.onAbsorb(vel);
}
} else {
mTouchMode = TOUCH_MODE_REST;
if (mPositionScroller != null) {
mPositionScroller.stop();
}
}
invalidate();
postOnAnimation(this);
}
void startScroll(int distance, int duration, boolean linear,
boolean suppressEndFlingStateChangeCall) {
int initialY = distance < 0 ? Integer.MAX_VALUE : 0;
mLastFlingY = initialY;
mScroller.setInterpolator(linear ? sLinearInterpolator : null);
mScroller.startScroll(0, initialY, 0, distance, duration);
mTouchMode = TOUCH_MODE_FLING;
mSuppressIdleStateChangeCall = suppressEndFlingStateChangeCall;
postOnAnimation(this);
}
// To interrupt a fling early you should use smoothScrollBy(0,0) instead
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P)
void endFling() {
mTouchMode = TOUCH_MODE_REST;
removeCallbacks(this);
removeCallbacks(mCheckFlywheel);
if (!mSuppressIdleStateChangeCall) {
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
}
clearScrollingCache();
mScroller.abortAnimation();
if (mFlingStrictSpan != null) {
mFlingStrictSpan.finish();
mFlingStrictSpan = null;
}
}
void flywheelTouch() {
postDelayed(mCheckFlywheel, FLYWHEEL_TIMEOUT);
}
@Override
public void run() {
switch (mTouchMode) {
default:
endFling();
return;
case TOUCH_MODE_SCROLL:
if (mScroller.isFinished()) {
return;
}
// Fall through
case TOUCH_MODE_FLING: {
if (mDataChanged) {
layoutChildren();
}
if (mItemCount == 0 || getChildCount() == 0) {
endFling();
return;
}
final OverScroller scroller = mScroller;
boolean more = scroller.computeScrollOffset();
final int y = scroller.getCurrY();
// Flip sign to convert finger direction to list items direction
// (e.g. finger moving down means list is moving towards the top)
int delta = mLastFlingY - y;
// Pretend that each frame of a fling scroll is a touch scroll
if (delta > 0) {
// List is moving towards the top. Use first view as mMotionPosition
mMotionPosition = mFirstPosition;
final View firstView = getChildAt(0);
mMotionViewOriginalTop = firstView.getTop();
// Don't fling more than 1 screen
delta = Math.min(getHeight() - mPaddingBottom - mPaddingTop - 1, delta);
} else {
// List is moving towards the bottom. Use last view as mMotionPosition
int offsetToLast = getChildCount() - 1;
mMotionPosition = mFirstPosition + offsetToLast;
final View lastView = getChildAt(offsetToLast);
mMotionViewOriginalTop = lastView.getTop();
// Don't fling more than 1 screen
delta = Math.max(-(getHeight() - mPaddingBottom - mPaddingTop - 1), delta);
}
// Check to see if we have bumped into the scroll limit
View motionView = getChildAt(mMotionPosition - mFirstPosition);
int oldTop = 0;
if (motionView != null) {
oldTop = motionView.getTop();
}
// Don't stop just because delta is zero (it could have been rounded)
final boolean atEdge = trackMotionScroll(delta, delta);
final boolean atEnd = atEdge && (delta != 0);
if (atEnd) {
if (motionView != null) {
// Tweak the scroll for how far we overshot
int overshoot = -(delta - (motionView.getTop() - oldTop));
overScrollBy(0, overshoot, 0, mScrollY, 0, 0,
0, mOverflingDistance, false);
}
if (more) {
edgeReached(delta);
}
break;
}
if (more && !atEnd) {
if (atEdge) invalidate();
mLastFlingY = y;
postOnAnimation(this);
} else {
endFling();
if (PROFILE_FLINGING) {
if (mFlingProfilingStarted) {
Debug.stopMethodTracing();
mFlingProfilingStarted = false;
}
if (mFlingStrictSpan != null) {
mFlingStrictSpan.finish();
mFlingStrictSpan = null;
}
}
}
break;
}
case TOUCH_MODE_OVERFLING: {
final OverScroller scroller = mScroller;
if (scroller.computeScrollOffset()) {
final int scrollY = mScrollY;
final int currY = scroller.getCurrY();
final int deltaY = currY - scrollY;
if (overScrollBy(0, deltaY, 0, scrollY, 0, 0,
0, mOverflingDistance, false)) {
final boolean crossDown = scrollY <= 0 && currY > 0;
final boolean crossUp = scrollY >= 0 && currY < 0;
if (crossDown || crossUp) {
int velocity = (int) scroller.getCurrVelocity();
if (crossUp) velocity = -velocity;
// Don't flywheel from this; we're just continuing things.
scroller.abortAnimation();
start(velocity);
} else {
startSpringback();
}
} else {
invalidate();
postOnAnimation(this);
}
} else {
endFling();
}
break;
}
}
}
}
/**
* The amount of friction applied to flings. The default value
* is {@link ViewConfiguration#getScrollFriction}.
*/
public void setFriction(float friction) {
if (mFlingRunnable == null) {
mFlingRunnable = new FlingRunnable();
}
mFlingRunnable.mScroller.setFriction(friction);
}
/**
* Sets a scale factor for the fling velocity. The initial scale
* factor is 1.0.
*
* @param scale The scale factor to multiply the velocity by.
*/
public void setVelocityScale(float scale) {
mVelocityScale = scale;
}
/**
* Override this for better control over position scrolling.
*/
AbsPositionScroller createPositionScroller() {
return new PositionScroller();
}
/**
* Smoothly scroll to the specified adapter position. The view will
* scroll such that the indicated position is displayed.
* @param position Scroll to this adapter position.
*/
public void smoothScrollToPosition(int position) {
if (mPositionScroller == null) {
mPositionScroller = createPositionScroller();
}
mPositionScroller.start(position);
}
/**
* Smoothly scroll to the specified adapter position. The view will scroll
* such that the indicated position is displayed offset
pixels below
* the top edge of the view. If this is impossible, (e.g. the offset would scroll
* the first or last item beyond the boundaries of the list) it will get as close
* as possible. The scroll will take duration
milliseconds to complete.
*
* @param position Position to scroll to
* @param offset Desired distance in pixels of position
from the top
* of the view when scrolling is finished
* @param duration Number of milliseconds to use for the scroll
*/
public void smoothScrollToPositionFromTop(int position, int offset, int duration) {
if (mPositionScroller == null) {
mPositionScroller = createPositionScroller();
}
mPositionScroller.startWithOffset(position, offset, duration);
}
/**
* Smoothly scroll to the specified adapter position. The view will scroll
* such that the indicated position is displayed offset
pixels below
* the top edge of the view. If this is impossible, (e.g. the offset would scroll
* the first or last item beyond the boundaries of the list) it will get as close
* as possible.
*
* @param position Position to scroll to
* @param offset Desired distance in pixels of position
from the top
* of the view when scrolling is finished
*/
public void smoothScrollToPositionFromTop(int position, int offset) {
if (mPositionScroller == null) {
mPositionScroller = createPositionScroller();
}
mPositionScroller.startWithOffset(position, offset);
}
/**
* Smoothly scroll to the specified adapter position. The view will
* scroll such that the indicated position is displayed, but it will
* stop early if scrolling further would scroll boundPosition out of
* view.
*
* @param position Scroll to this adapter position.
* @param boundPosition Do not scroll if it would move this adapter
* position out of view.
*/
public void smoothScrollToPosition(int position, int boundPosition) {
if (mPositionScroller == null) {
mPositionScroller = createPositionScroller();
}
mPositionScroller.start(position, boundPosition);
}
/**
* Smoothly scroll by distance pixels over duration milliseconds.
* @param distance Distance to scroll in pixels.
* @param duration Duration of the scroll animation in milliseconds.
*/
public void smoothScrollBy(int distance, int duration) {
smoothScrollBy(distance, duration, false, false);
}
@UnsupportedAppUsage
void smoothScrollBy(int distance, int duration, boolean linear,
boolean suppressEndFlingStateChangeCall) {
if (mFlingRunnable == null) {
mFlingRunnable = new FlingRunnable();
}
// No sense starting to scroll if we're not going anywhere
final int firstPos = mFirstPosition;
final int childCount = getChildCount();
final int lastPos = firstPos + childCount;
final int topLimit = getPaddingTop();
final int bottomLimit = getHeight() - getPaddingBottom();
if (distance == 0 || mItemCount == 0 || childCount == 0 ||
(firstPos == 0 && getChildAt(0).getTop() == topLimit && distance < 0) ||
(lastPos == mItemCount &&
getChildAt(childCount - 1).getBottom() == bottomLimit && distance > 0)) {
mFlingRunnable.endFling();
if (mPositionScroller != null) {
mPositionScroller.stop();
}
} else {
reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING);
mFlingRunnable.startScroll(distance, duration, linear, suppressEndFlingStateChangeCall);
}
}
/**
* Allows RemoteViews to scroll relatively to a position.
*/
void smoothScrollByOffset(int position) {
int index = -1;
if (position < 0) {
index = getFirstVisiblePosition();
} else if (position > 0) {
index = getLastVisiblePosition();
}
if (index > -1) {
View child = getChildAt(index - getFirstVisiblePosition());
if (child != null) {
Rect visibleRect = new Rect();
if (child.getGlobalVisibleRect(visibleRect)) {
// the child is partially visible
int childRectArea = child.getWidth() * child.getHeight();
int visibleRectArea = visibleRect.width() * visibleRect.height();
float visibleArea = (visibleRectArea / (float) childRectArea);
final float visibleThreshold = 0.75f;
if ((position < 0) && (visibleArea < visibleThreshold)) {
// the top index is not perceivably visible so offset
// to account for showing that top index as well
++index;
} else if ((position > 0) && (visibleArea < visibleThreshold)) {
// the bottom index is not perceivably visible so offset
// to account for showing that bottom index as well
--index;
}
}
smoothScrollToPosition(Math.max(0, Math.min(getCount(), index + position)));
}
}
}
private void createScrollingCache() {
if (mScrollingCacheEnabled && !mCachingStarted && !isHardwareAccelerated()) {
setChildrenDrawnWithCacheEnabled(true);
setChildrenDrawingCacheEnabled(true);
mCachingStarted = mCachingActive = true;
}
}
private void clearScrollingCache() {
if (!isHardwareAccelerated()) {
if (mClearScrollingCache == null) {
mClearScrollingCache = new Runnable() {
@Override
public void run() {
if (mCachingStarted) {
mCachingStarted = mCachingActive = false;
setChildrenDrawnWithCacheEnabled(false);
if ((mPersistentDrawingCache & PERSISTENT_SCROLLING_CACHE) == 0) {
setChildrenDrawingCacheEnabled(false);
}
if (!isAlwaysDrawnWithCacheEnabled()) {
invalidate();
}
}
}
};
}
post(mClearScrollingCache);
}
}
/**
* Scrolls the list items within the view by a specified number of pixels.
*
* The actual amount of scroll is capped by the list content viewport height
* which is the list height minus top and bottom paddings minus one pixel.
*
* @param y the amount of pixels to scroll by vertically
* @see #canScrollList(int)
*/
public void scrollListBy(int y) {
trackMotionScroll(-y, -y);
}
/**
* Check if the items in the list can be scrolled in a certain direction.
*
* @param direction Negative to check scrolling up, positive to check
* scrolling down.
* @return true if the list can be scrolled in the specified direction,
* false otherwise.
* @see #scrollListBy(int)
*/
public boolean canScrollList(int direction) {
final int childCount = getChildCount();
if (childCount == 0) {
return false;
}
final int firstPosition = mFirstPosition;
final Rect listPadding = mListPadding;
if (direction > 0) {
final int lastBottom = getChildAt(childCount - 1).getBottom();
final int lastPosition = firstPosition + childCount;
return lastPosition < mItemCount || lastBottom > getHeight() - listPadding.bottom;
} else {
final int firstTop = getChildAt(0).getTop();
return firstPosition > 0 || firstTop < listPadding.top;
}
}
/**
* Track a motion scroll
*
* @param deltaY Amount to offset mMotionView. This is the accumulated delta since the motion
* began. Positive numbers mean the user's finger is moving down the screen.
* @param incrementalDeltaY Change in deltaY from the previous event.
* @return true if we're already at the beginning/end of the list and have nothing to do.
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 124051739)
boolean trackMotionScroll(int deltaY, int incrementalDeltaY) {
final int childCount = getChildCount();
if (childCount == 0) {
return true;
}
final int firstTop = getChildAt(0).getTop();
final int lastBottom = getChildAt(childCount - 1).getBottom();
final Rect listPadding = mListPadding;
// "effective padding" In this case is the amount of padding that affects
// how much space should not be filled by items. If we don't clip to padding
// there is no effective padding.
int effectivePaddingTop = 0;
int effectivePaddingBottom = 0;
if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) {
effectivePaddingTop = listPadding.top;
effectivePaddingBottom = listPadding.bottom;
}
// FIXME account for grid vertical spacing too?
final int spaceAbove = effectivePaddingTop - firstTop;
final int end = getHeight() - effectivePaddingBottom;
final int spaceBelow = lastBottom - end;
final int height = getHeight() - mPaddingBottom - mPaddingTop;
if (deltaY < 0) {
deltaY = Math.max(-(height - 1), deltaY);
} else {
deltaY = Math.min(height - 1, deltaY);
}
if (incrementalDeltaY < 0) {
incrementalDeltaY = Math.max(-(height - 1), incrementalDeltaY);
} else {
incrementalDeltaY = Math.min(height - 1, incrementalDeltaY);
}
final int firstPosition = mFirstPosition;
// Update our guesses for where the first and last views are
if (firstPosition == 0) {
mFirstPositionDistanceGuess = firstTop - listPadding.top;
} else {
mFirstPositionDistanceGuess += incrementalDeltaY;
}
if (firstPosition + childCount == mItemCount) {
mLastPositionDistanceGuess = lastBottom + listPadding.bottom;
} else {
mLastPositionDistanceGuess += incrementalDeltaY;
}
final boolean cannotScrollDown = (firstPosition == 0 &&
firstTop >= listPadding.top && incrementalDeltaY >= 0);
final boolean cannotScrollUp = (firstPosition + childCount == mItemCount &&
lastBottom <= getHeight() - listPadding.bottom && incrementalDeltaY <= 0);
if (cannotScrollDown || cannotScrollUp) {
return incrementalDeltaY != 0;
}
final boolean down = incrementalDeltaY < 0;
final boolean inTouchMode = isInTouchMode();
if (inTouchMode) {
hideSelector();
}
final int headerViewsCount = getHeaderViewsCount();
final int footerViewsStart = mItemCount - getFooterViewsCount();
int start = 0;
int count = 0;
if (down) {
int top = -incrementalDeltaY;
if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) {
top += listPadding.top;
}
for (int i = 0; i < childCount; i++) {
final View child = getChildAt(i);
if (child.getBottom() >= top) {
break;
} else {
count++;
int position = firstPosition + i;
if (position >= headerViewsCount && position < footerViewsStart) {
// The view will be rebound to new data, clear any
// system-managed transient state.
child.clearAccessibilityFocus();
mRecycler.addScrapView(child, position);
}
}
}
} else {
int bottom = getHeight() - incrementalDeltaY;
if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) {
bottom -= listPadding.bottom;
}
for (int i = childCount - 1; i >= 0; i--) {
final View child = getChildAt(i);
if (child.getTop() <= bottom) {
break;
} else {
start = i;
count++;
int position = firstPosition + i;
if (position >= headerViewsCount && position < footerViewsStart) {
// The view will be rebound to new data, clear any
// system-managed transient state.
child.clearAccessibilityFocus();
mRecycler.addScrapView(child, position);
}
}
}
}
mMotionViewNewTop = mMotionViewOriginalTop + deltaY;
mBlockLayoutRequests = true;
if (count > 0) {
detachViewsFromParent(start, count);
mRecycler.removeSkippedScrap();
}
// invalidate before moving the children to avoid unnecessary invalidate
// calls to bubble up from the children all the way to the top
if (!awakenScrollBars()) {
invalidate();
}
offsetChildrenTopAndBottom(incrementalDeltaY);
if (down) {
mFirstPosition += count;
}
final int absIncrementalDeltaY = Math.abs(incrementalDeltaY);
if (spaceAbove < absIncrementalDeltaY || spaceBelow < absIncrementalDeltaY) {
fillGap(down);
}
mRecycler.fullyDetachScrapViews();
boolean selectorOnScreen = false;
if (!inTouchMode && mSelectedPosition != INVALID_POSITION) {
final int childIndex = mSelectedPosition - mFirstPosition;
if (childIndex >= 0 && childIndex < getChildCount()) {
positionSelector(mSelectedPosition, getChildAt(childIndex));
selectorOnScreen = true;
}
} else if (mSelectorPosition != INVALID_POSITION) {
final int childIndex = mSelectorPosition - mFirstPosition;
if (childIndex >= 0 && childIndex < getChildCount()) {
positionSelector(mSelectorPosition, getChildAt(childIndex));
selectorOnScreen = true;
}
}
if (!selectorOnScreen) {
mSelectorRect.setEmpty();
}
mBlockLayoutRequests = false;
invokeOnItemScrollListener();
return false;
}
/**
* Returns the number of header views in the list. Header views are special views
* at the top of the list that should not be recycled during a layout.
*
* @return The number of header views, 0 in the default implementation.
*/
int getHeaderViewsCount() {
return 0;
}
/**
* Returns the number of footer views in the list. Footer views are special views
* at the bottom of the list that should not be recycled during a layout.
*
* @return The number of footer views, 0 in the default implementation.
*/
int getFooterViewsCount() {
return 0;
}
/**
* Fills the gap left open by a touch-scroll. During a touch scroll, children that
* remain on screen are shifted and the other ones are discarded. The role of this
* method is to fill the gap thus created by performing a partial layout in the
* empty space.
*
* @param down true if the scroll is going down, false if it is going up
*/
@SuppressWarnings("HiddenAbstractMethod")
abstract void fillGap(boolean down);
void hideSelector() {
if (mSelectedPosition != INVALID_POSITION) {
if (mLayoutMode != LAYOUT_SPECIFIC) {
mResurrectToPosition = mSelectedPosition;
}
if (mNextSelectedPosition >= 0 && mNextSelectedPosition != mSelectedPosition) {
mResurrectToPosition = mNextSelectedPosition;
}
setSelectedPositionInt(INVALID_POSITION);
setNextSelectedPositionInt(INVALID_POSITION);
mSelectedTop = 0;
}
}
/**
* @return A position to select. First we try mSelectedPosition. If that has been clobbered by
* entering touch mode, we then try mResurrectToPosition. Values are pinned to the range
* of items available in the adapter
*/
int reconcileSelectedPosition() {
int position = mSelectedPosition;
if (position < 0) {
position = mResurrectToPosition;
}
position = Math.max(0, position);
position = Math.min(position, mItemCount - 1);
return position;
}
/**
* Find the row closest to y. This row will be used as the motion row when scrolling
*
* @param y Where the user touched
* @return The position of the first (or only) item in the row containing y
*/
@SuppressWarnings("HiddenAbstractMethod")
@UnsupportedAppUsage
abstract int findMotionRow(int y);
/**
* Find the row closest to y. This row will be used as the motion row when scrolling.
*
* @param y Where the user touched
* @return The position of the first (or only) item in the row closest to y
*/
int findClosestMotionRow(int y) {
final int childCount = getChildCount();
if (childCount == 0) {
return INVALID_POSITION;
}
final int motionRow = findMotionRow(y);
return motionRow != INVALID_POSITION ? motionRow : mFirstPosition + childCount - 1;
}
/**
* Causes all the views to be rebuilt and redrawn.
*/
public void invalidateViews() {
mDataChanged = true;
rememberSyncState();
requestLayout();
invalidate();
}
/**
* If there is a selection returns false.
* Otherwise resurrects the selection and returns true if resurrected.
*/
@UnsupportedAppUsage
boolean resurrectSelectionIfNeeded() {
if (mSelectedPosition < 0 && resurrectSelection()) {
updateSelectorState();
return true;
}
return false;
}
/**
* Makes the item at the supplied position selected.
*
* @param position the position of the new selection
*/
@SuppressWarnings("HiddenAbstractMethod")
abstract void setSelectionInt(int position);
/**
* Attempt to bring the selection back if the user is switching from touch
* to trackball mode
* @return Whether selection was set to something.
*/
boolean resurrectSelection() {
final int childCount = getChildCount();
if (childCount <= 0) {
return false;
}
int selectedTop = 0;
int selectedPos;
int childrenTop = mListPadding.top;
int childrenBottom = mBottom - mTop - mListPadding.bottom;
final int firstPosition = mFirstPosition;
final int toPosition = mResurrectToPosition;
boolean down = true;
if (toPosition >= firstPosition && toPosition < firstPosition + childCount) {
selectedPos = toPosition;
final View selected = getChildAt(selectedPos - mFirstPosition);
selectedTop = selected.getTop();
int selectedBottom = selected.getBottom();
// We are scrolled, don't get in the fade
if (selectedTop < childrenTop) {
selectedTop = childrenTop + getVerticalFadingEdgeLength();
} else if (selectedBottom > childrenBottom) {
selectedTop = childrenBottom - selected.getMeasuredHeight()
- getVerticalFadingEdgeLength();
}
} else {
if (toPosition < firstPosition) {
// Default to selecting whatever is first
selectedPos = firstPosition;
for (int i = 0; i < childCount; i++) {
final View v = getChildAt(i);
final int top = v.getTop();
if (i == 0) {
// Remember the position of the first item
selectedTop = top;
// See if we are scrolled at all
if (firstPosition > 0 || top < childrenTop) {
// If we are scrolled, don't select anything that is
// in the fade region
childrenTop += getVerticalFadingEdgeLength();
}
}
if (top >= childrenTop) {
// Found a view whose top is fully visisble
selectedPos = firstPosition + i;
selectedTop = top;
break;
}
}
} else {
final int itemCount = mItemCount;
down = false;
selectedPos = firstPosition + childCount - 1;
for (int i = childCount - 1; i >= 0; i--) {
final View v = getChildAt(i);
final int top = v.getTop();
final int bottom = v.getBottom();
if (i == childCount - 1) {
selectedTop = top;
if (firstPosition + childCount < itemCount || bottom > childrenBottom) {
childrenBottom -= getVerticalFadingEdgeLength();
}
}
if (bottom <= childrenBottom) {
selectedPos = firstPosition + i;
selectedTop = top;
break;
}
}
}
}
mResurrectToPosition = INVALID_POSITION;
removeCallbacks(mFlingRunnable);
if (mPositionScroller != null) {
mPositionScroller.stop();
}
mTouchMode = TOUCH_MODE_REST;
clearScrollingCache();
mSpecificTop = selectedTop;
selectedPos = lookForSelectablePosition(selectedPos, down);
if (selectedPos >= firstPosition && selectedPos <= getLastVisiblePosition()) {
mLayoutMode = LAYOUT_SPECIFIC;
updateSelectorState();
setSelectionInt(selectedPos);
invokeOnItemScrollListener();
} else {
selectedPos = INVALID_POSITION;
}
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
return selectedPos >= 0;
}
void confirmCheckedPositionsById() {
// Clear out the positional check states, we'll rebuild it below from IDs.
mCheckStates.clear();
boolean checkedCountChanged = false;
for (int checkedIndex = 0; checkedIndex < mCheckedIdStates.size(); checkedIndex++) {
final long id = mCheckedIdStates.keyAt(checkedIndex);
final int lastPos = mCheckedIdStates.valueAt(checkedIndex);
final long lastPosId = mAdapter.getItemId(lastPos);
if (id != lastPosId) {
// Look around to see if the ID is nearby. If not, uncheck it.
final int start = Math.max(0, lastPos - CHECK_POSITION_SEARCH_DISTANCE);
final int end = Math.min(lastPos + CHECK_POSITION_SEARCH_DISTANCE, mItemCount);
boolean found = false;
for (int searchPos = start; searchPos < end; searchPos++) {
final long searchId = mAdapter.getItemId(searchPos);
if (id == searchId) {
found = true;
mCheckStates.put(searchPos, true);
mCheckedIdStates.setValueAt(checkedIndex, searchPos);
break;
}
}
if (!found) {
mCheckedIdStates.delete(id);
checkedIndex--;
mCheckedItemCount--;
checkedCountChanged = true;
if (mChoiceActionMode != null && mMultiChoiceModeCallback != null) {
mMultiChoiceModeCallback.onItemCheckedStateChanged(mChoiceActionMode,
lastPos, id, false);
}
}
} else {
mCheckStates.put(lastPos, true);
}
}
if (checkedCountChanged && mChoiceActionMode != null) {
mChoiceActionMode.invalidate();
}
}
@Override
protected void handleDataChanged() {
int count = mItemCount;
int lastHandledItemCount = mLastHandledItemCount;
mLastHandledItemCount = mItemCount;
if (mChoiceMode != CHOICE_MODE_NONE && mAdapter != null && mAdapter.hasStableIds()) {
confirmCheckedPositionsById();
}
// TODO: In the future we can recycle these views based on stable ID instead.
mRecycler.clearTransientStateViews();
if (count > 0) {
int newPos;
int selectablePos;
// Find the row we are supposed to sync to
if (mNeedSync) {
// Update this first, since setNextSelectedPositionInt inspects it
mNeedSync = false;
mPendingSync = null;
if (mTranscriptMode == TRANSCRIPT_MODE_ALWAYS_SCROLL) {
mLayoutMode = LAYOUT_FORCE_BOTTOM;
return;
} else if (mTranscriptMode == TRANSCRIPT_MODE_NORMAL) {
if (mForceTranscriptScroll) {
mForceTranscriptScroll = false;
mLayoutMode = LAYOUT_FORCE_BOTTOM;
return;
}
final int childCount = getChildCount();
final int listBottom = getHeight() - getPaddingBottom();
final View lastChild = getChildAt(childCount - 1);
final int lastBottom = lastChild != null ? lastChild.getBottom() : listBottom;
if (mFirstPosition + childCount >= lastHandledItemCount &&
lastBottom <= listBottom) {
mLayoutMode = LAYOUT_FORCE_BOTTOM;
return;
}
// Something new came in and we didn't scroll; give the user a clue that
// there's something new.
awakenScrollBars();
}
switch (mSyncMode) {
case SYNC_SELECTED_POSITION:
if (isInTouchMode()) {
// We saved our state when not in touch mode. (We know this because
// mSyncMode is SYNC_SELECTED_POSITION.) Now we are trying to
// restore in touch mode. Just leave mSyncPosition as it is (possibly
// adjusting if the available range changed) and return.
mLayoutMode = LAYOUT_SYNC;
mSyncPosition = Math.min(Math.max(0, mSyncPosition), count - 1);
return;
} else {
// See if we can find a position in the new data with the same
// id as the old selection. This will change mSyncPosition.
newPos = findSyncPosition();
if (newPos >= 0) {
// Found it. Now verify that new selection is still selectable
selectablePos = lookForSelectablePosition(newPos, true);
if (selectablePos == newPos) {
// Same row id is selected
mSyncPosition = newPos;
if (mSyncHeight == getHeight()) {
// If we are at the same height as when we saved state, try
// to restore the scroll position too.
mLayoutMode = LAYOUT_SYNC;
} else {
// We are not the same height as when the selection was saved, so
// don't try to restore the exact position
mLayoutMode = LAYOUT_SET_SELECTION;
}
// Restore selection
setNextSelectedPositionInt(newPos);
return;
}
}
}
break;
case SYNC_FIRST_POSITION:
// Leave mSyncPosition as it is -- just pin to available range
mLayoutMode = LAYOUT_SYNC;
mSyncPosition = Math.min(Math.max(0, mSyncPosition), count - 1);
return;
}
}
if (!isInTouchMode()) {
// We couldn't find matching data -- try to use the same position
newPos = getSelectedItemPosition();
// Pin position to the available range
if (newPos >= count) {
newPos = count - 1;
}
if (newPos < 0) {
newPos = 0;
}
// Make sure we select something selectable -- first look down
selectablePos = lookForSelectablePosition(newPos, true);
if (selectablePos >= 0) {
setNextSelectedPositionInt(selectablePos);
return;
} else {
// Looking down didn't work -- try looking up
selectablePos = lookForSelectablePosition(newPos, false);
if (selectablePos >= 0) {
setNextSelectedPositionInt(selectablePos);
return;
}
}
} else {
// We already know where we want to resurrect the selection
if (mResurrectToPosition >= 0) {
return;
}
}
}
// Nothing is selected. Give up and reset everything.
mLayoutMode = mStackFromBottom ? LAYOUT_FORCE_BOTTOM : LAYOUT_FORCE_TOP;
mSelectedPosition = INVALID_POSITION;
mSelectedRowId = INVALID_ROW_ID;
mNextSelectedPosition = INVALID_POSITION;
mNextSelectedRowId = INVALID_ROW_ID;
mNeedSync = false;
mPendingSync = null;
mSelectorPosition = INVALID_POSITION;
checkSelectionChanged();
}
@Override
protected void onDisplayHint(int hint) {
super.onDisplayHint(hint);
switch (hint) {
case INVISIBLE:
if (mPopup != null && mPopup.isShowing()) {
dismissPopup();
}
break;
case VISIBLE:
if (mFiltered && mPopup != null && !mPopup.isShowing()) {
showPopup();
}
break;
}
mPopupHidden = hint == INVISIBLE;
}
/**
* Removes the filter window
*/
private void dismissPopup() {
if (mPopup != null) {
mPopup.dismiss();
}
}
/**
* Shows the filter window
*/
private void showPopup() {
// Make sure we have a window before showing the popup
if (getWindowVisibility() == View.VISIBLE) {
createTextFilter(true);
positionPopup();
// Make sure we get focus if we are showing the popup
checkFocus();
}
}
private void positionPopup() {
int screenHeight = getResources().getDisplayMetrics().heightPixels;
final int[] xy = new int[2];
getLocationOnScreen(xy);
// TODO: The 20 below should come from the theme
// TODO: And the gravity should be defined in the theme as well
final int bottomGap = screenHeight - xy[1] - getHeight() + (int) (mDensityScale * 20);
if (!mPopup.isShowing()) {
mPopup.showAtLocation(this, Gravity.BOTTOM | Gravity.CENTER_HORIZONTAL,
xy[0], bottomGap);
} else {
mPopup.update(xy[0], bottomGap, -1, -1);
}
}
/**
* What is the distance between the source and destination rectangles given the direction of
* focus navigation between them? The direction basically helps figure out more quickly what is
* self evident by the relationship between the rects...
*
* @param source the source rectangle
* @param dest the destination rectangle
* @param direction the direction
* @return the distance between the rectangles
*/
static int getDistance(Rect source, Rect dest, int direction) {
int sX, sY; // source x, y
int dX, dY; // dest x, y
switch (direction) {
case View.FOCUS_RIGHT:
sX = source.right;
sY = source.top + source.height() / 2;
dX = dest.left;
dY = dest.top + dest.height() / 2;
break;
case View.FOCUS_DOWN:
sX = source.left + source.width() / 2;
sY = source.bottom;
dX = dest.left + dest.width() / 2;
dY = dest.top;
break;
case View.FOCUS_LEFT:
sX = source.left;
sY = source.top + source.height() / 2;
dX = dest.right;
dY = dest.top + dest.height() / 2;
break;
case View.FOCUS_UP:
sX = source.left + source.width() / 2;
sY = source.top;
dX = dest.left + dest.width() / 2;
dY = dest.bottom;
break;
case View.FOCUS_FORWARD:
case View.FOCUS_BACKWARD:
sX = source.right + source.width() / 2;
sY = source.top + source.height() / 2;
dX = dest.left + dest.width() / 2;
dY = dest.top + dest.height() / 2;
break;
default:
throw new IllegalArgumentException("direction must be one of "
+ "{FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT, "
+ "FOCUS_FORWARD, FOCUS_BACKWARD}.");
}
int deltaX = dX - sX;
int deltaY = dY - sY;
return deltaY * deltaY + deltaX * deltaX;
}
@Override
protected boolean isInFilterMode() {
return mFiltered;
}
/**
* Sends a key to the text filter window
*
* @param keyCode The keycode for the event
* @param event The actual key event
*
* @return True if the text filter handled the event, false otherwise.
*/
boolean sendToTextFilter(int keyCode, int count, KeyEvent event) {
if (!acceptFilter()) {
return false;
}
boolean handled = false;
boolean okToSend = true;
switch (keyCode) {
case KeyEvent.KEYCODE_DPAD_UP:
case KeyEvent.KEYCODE_DPAD_DOWN:
case KeyEvent.KEYCODE_DPAD_LEFT:
case KeyEvent.KEYCODE_DPAD_RIGHT:
case KeyEvent.KEYCODE_DPAD_CENTER:
case KeyEvent.KEYCODE_ENTER:
case KeyEvent.KEYCODE_NUMPAD_ENTER:
okToSend = false;
break;
case KeyEvent.KEYCODE_BACK:
if (mFiltered && mPopup != null && mPopup.isShowing()) {
if (event.getAction() == KeyEvent.ACTION_DOWN
&& event.getRepeatCount() == 0) {
KeyEvent.DispatcherState state = getKeyDispatcherState();
if (state != null) {
state.startTracking(event, this);
}
handled = true;
} else if (event.getAction() == KeyEvent.ACTION_UP
&& event.isTracking() && !event.isCanceled()) {
handled = true;
mTextFilter.setText("");
}
}
okToSend = false;
break;
case KeyEvent.KEYCODE_SPACE:
// Only send spaces once we are filtered
okToSend = mFiltered;
break;
}
if (okToSend) {
createTextFilter(true);
KeyEvent forwardEvent = event;
if (forwardEvent.getRepeatCount() > 0) {
forwardEvent = KeyEvent.changeTimeRepeat(event, event.getEventTime(), 0);
}
int action = event.getAction();
switch (action) {
case KeyEvent.ACTION_DOWN:
handled = mTextFilter.onKeyDown(keyCode, forwardEvent);
break;
case KeyEvent.ACTION_UP:
handled = mTextFilter.onKeyUp(keyCode, forwardEvent);
break;
case KeyEvent.ACTION_MULTIPLE:
handled = mTextFilter.onKeyMultiple(keyCode, count, event);
break;
}
}
return handled;
}
/**
* Return an InputConnection for editing of the filter text.
*/
@Override
public InputConnection onCreateInputConnection(EditorInfo outAttrs) {
if (isTextFilterEnabled()) {
if (mPublicInputConnection == null) {
mDefInputConnection = new BaseInputConnection(this, false);
mPublicInputConnection = new InputConnectionWrapper(outAttrs);
}
outAttrs.inputType = EditorInfo.TYPE_CLASS_TEXT | EditorInfo.TYPE_TEXT_VARIATION_FILTER;
outAttrs.imeOptions = EditorInfo.IME_ACTION_DONE;
return mPublicInputConnection;
}
return null;
}
private class InputConnectionWrapper implements InputConnection {
private final EditorInfo mOutAttrs;
private InputConnection mTarget;
public InputConnectionWrapper(EditorInfo outAttrs) {
mOutAttrs = outAttrs;
}
private InputConnection getTarget() {
if (mTarget == null) {
mTarget = getTextFilterInput().onCreateInputConnection(mOutAttrs);
}
return mTarget;
}
@Override
public boolean reportFullscreenMode(boolean enabled) {
// Use our own input connection, since it is
// the "real" one the IME is talking with.
return mDefInputConnection.reportFullscreenMode(enabled);
}
@Override
public boolean performEditorAction(int editorAction) {
// The editor is off in its own window; we need to be
// the one that does this.
if (editorAction == EditorInfo.IME_ACTION_DONE) {
InputMethodManager imm =
getContext().getSystemService(InputMethodManager.class);
if (imm != null) {
imm.hideSoftInputFromWindow(getWindowToken(), 0);
}
return true;
}
return false;
}
@Override
public boolean sendKeyEvent(KeyEvent event) {
// Use our own input connection, since the filter
// text view may not be shown in a window so has
// no ViewAncestor to dispatch events with.
return mDefInputConnection.sendKeyEvent(event);
}
@Override
public CharSequence getTextBeforeCursor(int n, int flags) {
if (mTarget == null) return "";
return mTarget.getTextBeforeCursor(n, flags);
}
@Override
public CharSequence getTextAfterCursor(int n, int flags) {
if (mTarget == null) return "";
return mTarget.getTextAfterCursor(n, flags);
}
@Override
public CharSequence getSelectedText(int flags) {
if (mTarget == null) return "";
return mTarget.getSelectedText(flags);
}
@Override
public SurroundingText getSurroundingText(int beforeLength, int afterLength, int flags) {
if (mTarget == null) return null;
return mTarget.getSurroundingText(beforeLength, afterLength, flags);
}
@Override
public int getCursorCapsMode(int reqModes) {
if (mTarget == null) return InputType.TYPE_TEXT_FLAG_CAP_SENTENCES;
return mTarget.getCursorCapsMode(reqModes);
}
@Override
public ExtractedText getExtractedText(ExtractedTextRequest request, int flags) {
return getTarget().getExtractedText(request, flags);
}
@Override
public boolean deleteSurroundingText(int beforeLength, int afterLength) {
return getTarget().deleteSurroundingText(beforeLength, afterLength);
}
@Override
public boolean deleteSurroundingTextInCodePoints(int beforeLength, int afterLength) {
return getTarget().deleteSurroundingTextInCodePoints(beforeLength, afterLength);
}
@Override
public boolean setComposingText(CharSequence text, int newCursorPosition) {
return getTarget().setComposingText(text, newCursorPosition);
}
@Override
public boolean setComposingRegion(int start, int end) {
return getTarget().setComposingRegion(start, end);
}
@Override
public boolean finishComposingText() {
return mTarget == null || mTarget.finishComposingText();
}
@Override
public boolean commitText(CharSequence text, int newCursorPosition) {
return getTarget().commitText(text, newCursorPosition);
}
@Override
public boolean commitCompletion(CompletionInfo text) {
return getTarget().commitCompletion(text);
}
@Override
public boolean commitCorrection(CorrectionInfo correctionInfo) {
return getTarget().commitCorrection(correctionInfo);
}
@Override
public boolean setSelection(int start, int end) {
return getTarget().setSelection(start, end);
}
@Override
public boolean performContextMenuAction(int id) {
return getTarget().performContextMenuAction(id);
}
@Override
public boolean beginBatchEdit() {
return getTarget().beginBatchEdit();
}
@Override
public boolean endBatchEdit() {
return getTarget().endBatchEdit();
}
@Override
public boolean clearMetaKeyStates(int states) {
return getTarget().clearMetaKeyStates(states);
}
@Override
public boolean performPrivateCommand(String action, Bundle data) {
return getTarget().performPrivateCommand(action, data);
}
@Override
public boolean requestCursorUpdates(int cursorUpdateMode) {
return getTarget().requestCursorUpdates(cursorUpdateMode);
}
@Override
public Handler getHandler() {
return getTarget().getHandler();
}
@Override
public void closeConnection() {
getTarget().closeConnection();
}
@Override
public boolean commitContent(InputContentInfo inputContentInfo, int flags, Bundle opts) {
return getTarget().commitContent(inputContentInfo, flags, opts);
}
}
/**
* For filtering we proxy an input connection to an internal text editor,
* and this allows the proxying to happen.
*/
@Override
public boolean checkInputConnectionProxy(View view) {
return view == mTextFilter;
}
/**
* Creates the window for the text filter and populates it with an EditText field;
*
* @param animateEntrance true if the window should appear with an animation
*/
private void createTextFilter(boolean animateEntrance) {
if (mPopup == null) {
PopupWindow p = new PopupWindow(getContext());
p.setFocusable(false);
p.setTouchable(false);
p.setInputMethodMode(PopupWindow.INPUT_METHOD_NOT_NEEDED);
p.setContentView(getTextFilterInput());
p.setWidth(LayoutParams.WRAP_CONTENT);
p.setHeight(LayoutParams.WRAP_CONTENT);
p.setBackgroundDrawable(null);
mPopup = p;
getViewTreeObserver().addOnGlobalLayoutListener(this);
mGlobalLayoutListenerAddedFilter = true;
}
if (animateEntrance) {
mPopup.setAnimationStyle(com.android.internal.R.style.Animation_TypingFilter);
} else {
mPopup.setAnimationStyle(com.android.internal.R.style.Animation_TypingFilterRestore);
}
}
private EditText getTextFilterInput() {
if (mTextFilter == null) {
final LayoutInflater layoutInflater = LayoutInflater.from(getContext());
mTextFilter = (EditText) layoutInflater.inflate(
com.android.internal.R.layout.typing_filter, null);
// For some reason setting this as the "real" input type changes
// the text view in some way that it doesn't work, and I don't
// want to figure out why this is.
mTextFilter.setRawInputType(EditorInfo.TYPE_CLASS_TEXT
| EditorInfo.TYPE_TEXT_VARIATION_FILTER);
mTextFilter.setImeOptions(EditorInfo.IME_FLAG_NO_EXTRACT_UI);
mTextFilter.addTextChangedListener(this);
}
return mTextFilter;
}
/**
* Clear the text filter.
*/
public void clearTextFilter() {
if (mFiltered) {
getTextFilterInput().setText("");
mFiltered = false;
if (mPopup != null && mPopup.isShowing()) {
dismissPopup();
}
}
}
/**
* Returns if the ListView currently has a text filter.
*/
public boolean hasTextFilter() {
return mFiltered;
}
@Override
public void onGlobalLayout() {
if (isShown()) {
// Show the popup if we are filtered
if (mFiltered && mPopup != null && !mPopup.isShowing() && !mPopupHidden) {
showPopup();
}
} else {
// Hide the popup when we are no longer visible
if (mPopup != null && mPopup.isShowing()) {
dismissPopup();
}
}
}
/**
* For our text watcher that is associated with the text filter. Does
* nothing.
*/
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
/**
* For our text watcher that is associated with the text filter. Performs
* the actual filtering as the text changes, and takes care of hiding and
* showing the popup displaying the currently entered filter text.
*/
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
if (isTextFilterEnabled()) {
createTextFilter(true);
int length = s.length();
boolean showing = mPopup.isShowing();
if (!showing && length > 0) {
// Show the filter popup if necessary
showPopup();
mFiltered = true;
} else if (showing && length == 0) {
// Remove the filter popup if the user has cleared all text
dismissPopup();
mFiltered = false;
}
if (mAdapter instanceof Filterable) {
Filter f = ((Filterable) mAdapter).getFilter();
// Filter should not be null when we reach this part
if (f != null) {
f.filter(s, this);
} else {
throw new IllegalStateException("You cannot call onTextChanged with a non "
+ "filterable adapter");
}
}
}
}
/**
* For our text watcher that is associated with the text filter. Does
* nothing.
*/
@Override
public void afterTextChanged(Editable s) {
}
@Override
public void onFilterComplete(int count) {
if (mSelectedPosition < 0 && count > 0) {
mResurrectToPosition = INVALID_POSITION;
resurrectSelection();
}
}
@Override
protected ViewGroup.LayoutParams generateDefaultLayoutParams() {
return new AbsListView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,
ViewGroup.LayoutParams.WRAP_CONTENT, 0);
}
@Override
protected ViewGroup.LayoutParams generateLayoutParams(ViewGroup.LayoutParams p) {
return new LayoutParams(p);
}
@Override
public LayoutParams generateLayoutParams(AttributeSet attrs) {
return new AbsListView.LayoutParams(getContext(), attrs);
}
@Override
protected boolean checkLayoutParams(ViewGroup.LayoutParams p) {
return p instanceof AbsListView.LayoutParams;
}
/**
* Puts the list or grid into transcript mode. In this mode the list or grid will always scroll
* to the bottom to show new items.
*
* @param mode the transcript mode to set
*
* @see #TRANSCRIPT_MODE_DISABLED
* @see #TRANSCRIPT_MODE_NORMAL
* @see #TRANSCRIPT_MODE_ALWAYS_SCROLL
*/
public void setTranscriptMode(int mode) {
mTranscriptMode = mode;
}
/**
* Returns the current transcript mode.
*
* @return {@link #TRANSCRIPT_MODE_DISABLED}, {@link #TRANSCRIPT_MODE_NORMAL} or
* {@link #TRANSCRIPT_MODE_ALWAYS_SCROLL}
*/
@InspectableProperty(enumMapping = {
@EnumEntry(value = TRANSCRIPT_MODE_DISABLED, name = "disabled"),
@EnumEntry(value = TRANSCRIPT_MODE_NORMAL, name = "normal"),
@EnumEntry(value = TRANSCRIPT_MODE_ALWAYS_SCROLL, name = "alwaysScroll")
})
public int getTranscriptMode() {
return mTranscriptMode;
}
@Override
public int getSolidColor() {
return mCacheColorHint;
}
/**
* When set to a non-zero value, the cache color hint indicates that this list is always drawn
* on top of a solid, single-color, opaque background.
*
* Zero means that what's behind this object is translucent (non solid) or is not made of a
* single color. This hint will not affect any existing background drawable set on this view (
* typically set via {@link #setBackgroundDrawable(Drawable)}).
*
* @param color The background color
*/
public void setCacheColorHint(@ColorInt int color) {
if (color != mCacheColorHint) {
mCacheColorHint = color;
int count = getChildCount();
for (int i = 0; i < count; i++) {
getChildAt(i).setDrawingCacheBackgroundColor(color);
}
mRecycler.setCacheColorHint(color);
}
}
/**
* When set to a non-zero value, the cache color hint indicates that this list is always drawn
* on top of a solid, single-color, opaque background
*
* @return The cache color hint
*/
@ViewDebug.ExportedProperty(category = "drawing")
@InspectableProperty
@ColorInt
public int getCacheColorHint() {
return mCacheColorHint;
}
/**
* Move all views (excluding headers and footers) held by this AbsListView into the supplied
* List. This includes views displayed on the screen as well as views stored in AbsListView's
* internal view recycler.
*
* @param views A list into which to put the reclaimed views
*/
public void reclaimViews(List views) {
int childCount = getChildCount();
RecyclerListener listener = mRecycler.mRecyclerListener;
// Reclaim views on screen
for (int i = 0; i < childCount; i++) {
View child = getChildAt(i);
AbsListView.LayoutParams lp = (AbsListView.LayoutParams) child.getLayoutParams();
// Don't reclaim header or footer views, or views that should be ignored
if (lp != null && mRecycler.shouldRecycleViewType(lp.viewType)) {
views.add(child);
child.setAccessibilityDelegate(null);
child.resetSubtreeAutofillIds();
if (listener != null) {
// Pretend they went through the scrap heap
listener.onMovedToScrapHeap(child);
}
}
}
mRecycler.reclaimScrapViews(views);
removeAllViewsInLayout();
}
private void finishGlows() {
if (shouldDisplayEdgeEffects()) {
mEdgeGlowTop.finish();
mEdgeGlowBottom.finish();
}
}
/**
* Sets up this AbsListView to use a remote views adapter which connects to a RemoteViewsService
* through the specified intent.
* @param intent the intent used to identify the RemoteViewsService for the adapter to connect to.
*/
public void setRemoteViewsAdapter(Intent intent) {
setRemoteViewsAdapter(intent, false);
}
/** @hide **/
public Runnable setRemoteViewsAdapterAsync(final Intent intent) {
return new RemoteViewsAdapter.AsyncRemoteAdapterAction(this, intent);
}
/** @hide **/
@Override
public void setRemoteViewsAdapter(Intent intent, boolean isAsync) {
// Ensure that we don't already have a RemoteViewsAdapter that is bound to an existing
// service handling the specified intent.
if (mRemoteAdapter != null) {
Intent.FilterComparison fcNew = new Intent.FilterComparison(intent);
Intent.FilterComparison fcOld = new Intent.FilterComparison(
mRemoteAdapter.getRemoteViewsServiceIntent());
if (fcNew.equals(fcOld)) {
return;
}
}
mDeferNotifyDataSetChanged = false;
// Otherwise, create a new RemoteViewsAdapter for binding
mRemoteAdapter = new RemoteViewsAdapter(getContext(), intent, this, isAsync);
if (mRemoteAdapter.isDataReady()) {
setAdapter(mRemoteAdapter);
}
}
/**
* Sets up the onClickHandler to be used by the RemoteViewsAdapter when inflating RemoteViews
*
* @param handler The OnClickHandler to use when inflating RemoteViews.
*
* @hide
*/
public void setRemoteViewsInteractionHandler(InteractionHandler handler) {
// Ensure that we don't already have a RemoteViewsAdapter that is bound to an existing
// service handling the specified intent.
if (mRemoteAdapter != null) {
mRemoteAdapter.setRemoteViewsInteractionHandler(handler);
}
}
/**
* This defers a notifyDataSetChanged on the pending RemoteViewsAdapter if it has not
* connected yet.
*/
@Override
public void deferNotifyDataSetChanged() {
mDeferNotifyDataSetChanged = true;
}
/**
* Called back when the adapter connects to the RemoteViewsService.
*/
@Override
public boolean onRemoteAdapterConnected() {
if (mRemoteAdapter != mAdapter) {
setAdapter(mRemoteAdapter);
if (mDeferNotifyDataSetChanged) {
mRemoteAdapter.notifyDataSetChanged();
mDeferNotifyDataSetChanged = false;
}
return false;
} else if (mRemoteAdapter != null) {
mRemoteAdapter.superNotifyDataSetChanged();
return true;
}
return false;
}
/**
* Called back when the adapter disconnects from the RemoteViewsService.
*/
@Override
public void onRemoteAdapterDisconnected() {
// If the remote adapter disconnects, we keep it around
// since the currently displayed items are still cached.
// Further, we want the service to eventually reconnect
// when necessary, as triggered by this view requesting
// items from the Adapter.
}
/**
* Hints the RemoteViewsAdapter, if it exists, about which views are currently
* being displayed by the AbsListView.
*/
void setVisibleRangeHint(int start, int end) {
if (mRemoteAdapter != null) {
mRemoteAdapter.setVisibleRangeHint(start, end);
}
}
/**
* Sets the edge effect color for both top and bottom edge effects.
*
* @param color The color for the edge effects.
* @see #setTopEdgeEffectColor(int)
* @see #setBottomEdgeEffectColor(int)
* @see #getTopEdgeEffectColor()
* @see #getBottomEdgeEffectColor()
*/
public void setEdgeEffectColor(@ColorInt int color) {
setTopEdgeEffectColor(color);
setBottomEdgeEffectColor(color);
}
/**
* Sets the bottom edge effect color.
*
* @param color The color for the bottom edge effect.
* @see #setTopEdgeEffectColor(int)
* @see #setEdgeEffectColor(int)
* @see #getTopEdgeEffectColor()
* @see #getBottomEdgeEffectColor()
*/
public void setBottomEdgeEffectColor(@ColorInt int color) {
mEdgeGlowBottom.setColor(color);
invalidateEdgeEffects();
}
/**
* Sets the top edge effect color.
*
* @param color The color for the top edge effect.
* @see #setBottomEdgeEffectColor(int)
* @see #setEdgeEffectColor(int)
* @see #getTopEdgeEffectColor()
* @see #getBottomEdgeEffectColor()
*/
public void setTopEdgeEffectColor(@ColorInt int color) {
mEdgeGlowTop.setColor(color);
invalidateEdgeEffects();
}
/**
* Returns the top edge effect color.
*
* @return The top edge effect color.
* @see #setEdgeEffectColor(int)
* @see #setTopEdgeEffectColor(int)
* @see #setBottomEdgeEffectColor(int)
* @see #getBottomEdgeEffectColor()
*/
@ColorInt
public int getTopEdgeEffectColor() {
return mEdgeGlowTop.getColor();
}
/**
* Returns the bottom edge effect color.
*
* @return The bottom edge effect color.
* @see #setEdgeEffectColor(int)
* @see #setTopEdgeEffectColor(int)
* @see #setBottomEdgeEffectColor(int)
* @see #getTopEdgeEffectColor()
*/
@ColorInt
public int getBottomEdgeEffectColor() {
return mEdgeGlowBottom.getColor();
}
/**
* Sets the recycler listener to be notified whenever a View is set aside in
* the recycler for later reuse. This listener can be used to free resources
* associated to the View.
*
* @param listener The recycler listener to be notified of views set aside
* in the recycler.
*
* @see android.widget.AbsListView.RecyclerListener
*/
public void setRecyclerListener(RecyclerListener listener) {
mRecycler.mRecyclerListener = listener;
}
class AdapterDataSetObserver extends AdapterView.AdapterDataSetObserver {
@Override
public void onChanged() {
super.onChanged();
if (mFastScroll != null) {
mFastScroll.onSectionsChanged();
}
}
@Override
public void onInvalidated() {
super.onInvalidated();
if (mFastScroll != null) {
mFastScroll.onSectionsChanged();
}
}
}
/**
* A MultiChoiceModeListener receives events for {@link AbsListView#CHOICE_MODE_MULTIPLE_MODAL}.
* It acts as the {@link ActionMode.Callback} for the selection mode and also receives
* {@link #onItemCheckedStateChanged(ActionMode, int, long, boolean)} events when the user
* selects and deselects list items.
*/
public interface MultiChoiceModeListener extends ActionMode.Callback {
/**
* Called when an item is checked or unchecked during selection mode.
*
* @param mode The {@link ActionMode} providing the selection mode
* @param position Adapter position of the item that was checked or unchecked
* @param id Adapter ID of the item that was checked or unchecked
* @param checked true
if the item is now checked, false
* if the item is now unchecked.
*/
public void onItemCheckedStateChanged(ActionMode mode,
int position, long id, boolean checked);
}
class MultiChoiceModeWrapper implements MultiChoiceModeListener {
private MultiChoiceModeListener mWrapped;
public void setWrapped(MultiChoiceModeListener wrapped) {
mWrapped = wrapped;
}
public boolean hasWrappedCallback() {
return mWrapped != null;
}
@Override
public boolean onCreateActionMode(ActionMode mode, Menu menu) {
if (mWrapped.onCreateActionMode(mode, menu)) {
// Initialize checked graphic state?
setLongClickable(false);
return true;
}
return false;
}
@Override
public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
return mWrapped.onPrepareActionMode(mode, menu);
}
@Override
public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
return mWrapped.onActionItemClicked(mode, item);
}
@Override
public void onDestroyActionMode(ActionMode mode) {
mWrapped.onDestroyActionMode(mode);
mChoiceActionMode = null;
// Ending selection mode means deselecting everything.
clearChoices();
mDataChanged = true;
rememberSyncState();
requestLayout();
setLongClickable(true);
}
@Override
public void onItemCheckedStateChanged(ActionMode mode,
int position, long id, boolean checked) {
mWrapped.onItemCheckedStateChanged(mode, position, id, checked);
// If there are no items selected we no longer need the selection mode.
if (getCheckedItemCount() == 0) {
mode.finish();
}
}
}
/**
* AbsListView extends LayoutParams to provide a place to hold the view type.
*/
public static class LayoutParams extends ViewGroup.LayoutParams {
/**
* View type for this view, as returned by
* {@link android.widget.Adapter#getItemViewType(int) }
*/
@ViewDebug.ExportedProperty(category = "list", mapping = {
@ViewDebug.IntToString(from = ITEM_VIEW_TYPE_IGNORE, to = "ITEM_VIEW_TYPE_IGNORE"),
@ViewDebug.IntToString(from = ITEM_VIEW_TYPE_HEADER_OR_FOOTER, to = "ITEM_VIEW_TYPE_HEADER_OR_FOOTER")
})
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023)
int viewType;
/**
* When this boolean is set, the view has been added to the AbsListView
* at least once. It is used to know whether headers/footers have already
* been added to the list view and whether they should be treated as
* recycled views or not.
*/
@ViewDebug.ExportedProperty(category = "list")
boolean recycledHeaderFooter;
/**
* When an AbsListView is measured with an AT_MOST measure spec, it needs
* to obtain children views to measure itself. When doing so, the children
* are not attached to the window, but put in the recycler which assumes
* they've been attached before. Setting this flag will force the reused
* view to be attached to the window rather than just attached to the
* parent.
*/
@ViewDebug.ExportedProperty(category = "list")
boolean forceAdd;
/**
* The position the view was removed from when pulled out of the
* scrap heap.
* @hide
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
int scrappedFromPosition;
/**
* The ID the view represents
*/
long itemId = -1;
/** Whether the adapter considers the item enabled. */
boolean isEnabled;
public LayoutParams(Context c, AttributeSet attrs) {
super(c, attrs);
}
public LayoutParams(int w, int h) {
super(w, h);
}
public LayoutParams(int w, int h, int viewType) {
super(w, h);
this.viewType = viewType;
}
public LayoutParams(ViewGroup.LayoutParams source) {
super(source);
}
/** @hide */
@Override
protected void encodeProperties(@NonNull ViewHierarchyEncoder encoder) {
super.encodeProperties(encoder);
encoder.addProperty("list:viewType", viewType);
encoder.addProperty("list:recycledHeaderFooter", recycledHeaderFooter);
encoder.addProperty("list:forceAdd", forceAdd);
encoder.addProperty("list:isEnabled", isEnabled);
}
}
/**
* A RecyclerListener is used to receive a notification whenever a View is placed
* inside the RecycleBin's scrap heap. This listener is used to free resources
* associated to Views placed in the RecycleBin.
*
* @see android.widget.AbsListView#setRecyclerListener(android.widget.AbsListView.RecyclerListener)
*/
public static interface RecyclerListener {
/**
* Indicates that the specified View was moved into the recycler's scrap heap.
* The view is not displayed on screen any more and any expensive resource
* associated with the view should be discarded.
*
* @param view
*/
void onMovedToScrapHeap(View view);
}
/**
* The RecycleBin facilitates reuse of views across layouts. The RecycleBin has two levels of
* storage: ActiveViews and ScrapViews. ActiveViews are those views which were onscreen at the
* start of a layout. By construction, they are displaying current information. At the end of
* layout, all views in ActiveViews are demoted to ScrapViews. ScrapViews are old views that
* could potentially be used by the adapter to avoid allocating views unnecessarily.
*
* @see android.widget.AbsListView#setRecyclerListener(android.widget.AbsListView.RecyclerListener)
* @see android.widget.AbsListView.RecyclerListener
*/
class RecycleBin {
@UnsupportedAppUsage
private RecyclerListener mRecyclerListener;
/**
* The position of the first view stored in mActiveViews.
*/
private int mFirstActivePosition;
/**
* Views that were on screen at the start of layout. This array is populated at the start of
* layout, and at the end of layout all view in mActiveViews are moved to mScrapViews.
* Views in mActiveViews represent a contiguous range of Views, with position of the first
* view store in mFirstActivePosition.
*/
private View[] mActiveViews = new View[0];
/**
* Unsorted views that can be used by the adapter as a convert view.
*/
private ArrayList[] mScrapViews;
private int mViewTypeCount;
private ArrayList mCurrentScrap;
private ArrayList mSkippedScrap;
private SparseArray mTransientStateViews;
private LongSparseArray mTransientStateViewsById;
public void setViewTypeCount(int viewTypeCount) {
if (viewTypeCount < 1) {
throw new IllegalArgumentException("Can't have a viewTypeCount < 1");
}
//noinspection unchecked
ArrayList[] scrapViews = new ArrayList[viewTypeCount];
for (int i = 0; i < viewTypeCount; i++) {
scrapViews[i] = new ArrayList();
}
mViewTypeCount = viewTypeCount;
mCurrentScrap = scrapViews[0];
mScrapViews = scrapViews;
}
public void markChildrenDirty() {
if (mViewTypeCount == 1) {
final ArrayList scrap = mCurrentScrap;
final int scrapCount = scrap.size();
for (int i = 0; i < scrapCount; i++) {
scrap.get(i).forceLayout();
}
} else {
final int typeCount = mViewTypeCount;
for (int i = 0; i < typeCount; i++) {
final ArrayList scrap = mScrapViews[i];
final int scrapCount = scrap.size();
for (int j = 0; j < scrapCount; j++) {
scrap.get(j).forceLayout();
}
}
}
if (mTransientStateViews != null) {
final int count = mTransientStateViews.size();
for (int i = 0; i < count; i++) {
mTransientStateViews.valueAt(i).forceLayout();
}
}
if (mTransientStateViewsById != null) {
final int count = mTransientStateViewsById.size();
for (int i = 0; i < count; i++) {
mTransientStateViewsById.valueAt(i).forceLayout();
}
}
}
public boolean shouldRecycleViewType(int viewType) {
return viewType >= 0;
}
/**
* Clears the scrap heap.
*/
@UnsupportedAppUsage
void clear() {
if (mViewTypeCount == 1) {
final ArrayList scrap = mCurrentScrap;
clearScrap(scrap);
} else {
final int typeCount = mViewTypeCount;
for (int i = 0; i < typeCount; i++) {
final ArrayList scrap = mScrapViews[i];
clearScrap(scrap);
}
}
clearTransientStateViews();
}
/**
* Fill ActiveViews with all of the children of the AbsListView.
*
* @param childCount The minimum number of views mActiveViews should hold
* @param firstActivePosition The position of the first view that will be stored in
* mActiveViews
*/
void fillActiveViews(int childCount, int firstActivePosition) {
if (mActiveViews.length < childCount) {
mActiveViews = new View[childCount];
}
mFirstActivePosition = firstActivePosition;
//noinspection MismatchedReadAndWriteOfArray
final View[] activeViews = mActiveViews;
for (int i = 0; i < childCount; i++) {
View child = getChildAt(i);
AbsListView.LayoutParams lp = (AbsListView.LayoutParams) child.getLayoutParams();
// Don't put header or footer views into the scrap heap
if (lp != null && lp.viewType != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) {
// Note: We do place AdapterView.ITEM_VIEW_TYPE_IGNORE in active views.
// However, we will NOT place them into scrap views.
activeViews[i] = child;
// Remember the position so that setupChild() doesn't reset state.
lp.scrappedFromPosition = firstActivePosition + i;
}
}
}
/**
* Get the view corresponding to the specified position. The view will be removed from
* mActiveViews if it is found.
*
* @param position The position to look up in mActiveViews
* @return The view if it is found, null otherwise
*/
View getActiveView(int position) {
int index = position - mFirstActivePosition;
final View[] activeViews = mActiveViews;
if (index >=0 && index < activeViews.length) {
final View match = activeViews[index];
activeViews[index] = null;
return match;
}
return null;
}
View getTransientStateView(int position) {
if (mAdapter != null && mAdapterHasStableIds && mTransientStateViewsById != null) {
long id = mAdapter.getItemId(position);
View result = mTransientStateViewsById.get(id);
mTransientStateViewsById.remove(id);
return result;
}
if (mTransientStateViews != null) {
final int index = mTransientStateViews.indexOfKey(position);
if (index >= 0) {
View result = mTransientStateViews.valueAt(index);
mTransientStateViews.removeAt(index);
return result;
}
}
return null;
}
/**
* Dumps and fully detaches any currently saved views with transient
* state.
*/
void clearTransientStateViews() {
final SparseArray viewsByPos = mTransientStateViews;
if (viewsByPos != null) {
final int N = viewsByPos.size();
for (int i = 0; i < N; i++) {
removeDetachedView(viewsByPos.valueAt(i), false);
}
viewsByPos.clear();
}
final LongSparseArray viewsById = mTransientStateViewsById;
if (viewsById != null) {
final int N = viewsById.size();
for (int i = 0; i < N; i++) {
removeDetachedView(viewsById.valueAt(i), false);
}
viewsById.clear();
}
}
/**
* @return A view from the ScrapViews collection. These are unordered.
*/
View getScrapView(int position) {
final int whichScrap = mAdapter.getItemViewType(position);
if (whichScrap < 0) {
return null;
}
if (mViewTypeCount == 1) {
return retrieveFromScrap(mCurrentScrap, position);
} else if (whichScrap < mScrapViews.length) {
return retrieveFromScrap(mScrapViews[whichScrap], position);
}
return null;
}
/**
* Puts a view into the list of scrap views.
*
* If the list data hasn't changed or the adapter has stable IDs, views
* with transient state will be preserved for later retrieval.
*
* @param scrap The view to add
* @param position The view's position within its parent
*/
void addScrapView(View scrap, int position) {
final AbsListView.LayoutParams lp = (AbsListView.LayoutParams) scrap.getLayoutParams();
if (lp == null) {
// Can't recycle, but we don't know anything about the view.
// Ignore it completely.
return;
}
lp.scrappedFromPosition = position;
// Remove but don't scrap header or footer views, or views that
// should otherwise not be recycled.
final int viewType = lp.viewType;
if (!shouldRecycleViewType(viewType)) {
// Can't recycle. If it's not a header or footer, which have
// special handling and should be ignored, then skip the scrap
// heap and we'll fully detach the view later.
if (viewType != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) {
getSkippedScrap().add(scrap);
}
return;
}
scrap.dispatchStartTemporaryDetach();
// The the accessibility state of the view may change while temporary
// detached and we do not allow detached views to fire accessibility
// events. So we are announcing that the subtree changed giving a chance
// to clients holding on to a view in this subtree to refresh it.
notifyViewAccessibilityStateChangedIfNeeded(
AccessibilityEvent.CONTENT_CHANGE_TYPE_SUBTREE);
// Don't scrap views that have transient state.
final boolean scrapHasTransientState = scrap.hasTransientState();
if (scrapHasTransientState) {
if (mAdapter != null && mAdapterHasStableIds) {
// If the adapter has stable IDs, we can reuse the view for
// the same data.
if (mTransientStateViewsById == null) {
mTransientStateViewsById = new LongSparseArray<>();
}
mTransientStateViewsById.put(lp.itemId, scrap);
} else if (!mDataChanged) {
// If the data hasn't changed, we can reuse the views at
// their old positions.
if (mTransientStateViews == null) {
mTransientStateViews = new SparseArray<>();
}
mTransientStateViews.put(position, scrap);
} else {
// Otherwise, we'll have to remove the view and start over.
clearScrapForRebind(scrap);
getSkippedScrap().add(scrap);
}
} else {
clearScrapForRebind(scrap);
if (mViewTypeCount == 1) {
mCurrentScrap.add(scrap);
} else {
mScrapViews[viewType].add(scrap);
}
if (mRecyclerListener != null) {
mRecyclerListener.onMovedToScrapHeap(scrap);
}
}
}
private ArrayList getSkippedScrap() {
if (mSkippedScrap == null) {
mSkippedScrap = new ArrayList<>();
}
return mSkippedScrap;
}
/**
* Finish the removal of any views that skipped the scrap heap.
*/
void removeSkippedScrap() {
if (mSkippedScrap == null) {
return;
}
final int count = mSkippedScrap.size();
for (int i = 0; i < count; i++) {
removeDetachedView(mSkippedScrap.get(i), false);
}
mSkippedScrap.clear();
}
/**
* Move all views remaining in mActiveViews to mScrapViews.
*/
void scrapActiveViews() {
final View[] activeViews = mActiveViews;
final boolean hasListener = mRecyclerListener != null;
final boolean multipleScraps = mViewTypeCount > 1;
ArrayList scrapViews = mCurrentScrap;
final int count = activeViews.length;
for (int i = count - 1; i >= 0; i--) {
final View victim = activeViews[i];
if (victim != null) {
final AbsListView.LayoutParams lp
= (AbsListView.LayoutParams) victim.getLayoutParams();
final int whichScrap = lp.viewType;
activeViews[i] = null;
if (victim.hasTransientState()) {
// Store views with transient state for later use.
victim.dispatchStartTemporaryDetach();
if (mAdapter != null && mAdapterHasStableIds) {
if (mTransientStateViewsById == null) {
mTransientStateViewsById = new LongSparseArray();
}
long id = mAdapter.getItemId(mFirstActivePosition + i);
mTransientStateViewsById.put(id, victim);
} else if (!mDataChanged) {
if (mTransientStateViews == null) {
mTransientStateViews = new SparseArray();
}
mTransientStateViews.put(mFirstActivePosition + i, victim);
} else if (whichScrap != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) {
// The data has changed, we can't keep this view.
removeDetachedView(victim, false);
}
} else if (!shouldRecycleViewType(whichScrap)) {
// Discard non-recyclable views except headers/footers.
if (whichScrap != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) {
removeDetachedView(victim, false);
}
} else {
// Store everything else on the appropriate scrap heap.
if (multipleScraps) {
scrapViews = mScrapViews[whichScrap];
}
lp.scrappedFromPosition = mFirstActivePosition + i;
removeDetachedView(victim, false);
scrapViews.add(victim);
if (hasListener) {
mRecyclerListener.onMovedToScrapHeap(victim);
}
}
}
}
pruneScrapViews();
}
/**
* At the end of a layout pass, all temp detached views should either be re-attached or
* completely detached. This method ensures that any remaining view in the scrap list is
* fully detached.
*/
void fullyDetachScrapViews() {
final int viewTypeCount = mViewTypeCount;
final ArrayList[] scrapViews = mScrapViews;
for (int i = 0; i < viewTypeCount; ++i) {
final ArrayList scrapPile = scrapViews[i];
for (int j = scrapPile.size() - 1; j >= 0; j--) {
final View view = scrapPile.get(j);
if (view.isTemporarilyDetached()) {
removeDetachedView(view, false);
}
}
}
}
/**
* Makes sure that the size of mScrapViews does not exceed the size of
* mActiveViews, which can happen if an adapter does not recycle its
* views. Removes cached transient state views that no longer have
* transient state.
*/
private void pruneScrapViews() {
final int maxViews = mActiveViews.length;
final int viewTypeCount = mViewTypeCount;
final ArrayList[] scrapViews = mScrapViews;
for (int i = 0; i < viewTypeCount; ++i) {
final ArrayList scrapPile = scrapViews[i];
int size = scrapPile.size();
while (size > maxViews) {
scrapPile.remove(--size);
}
}
final SparseArray transViewsByPos = mTransientStateViews;
if (transViewsByPos != null) {
for (int i = 0; i < transViewsByPos.size(); i++) {
final View v = transViewsByPos.valueAt(i);
if (!v.hasTransientState()) {
removeDetachedView(v, false);
transViewsByPos.removeAt(i);
i--;
}
}
}
final LongSparseArray transViewsById = mTransientStateViewsById;
if (transViewsById != null) {
for (int i = 0; i < transViewsById.size(); i++) {
final View v = transViewsById.valueAt(i);
if (!v.hasTransientState()) {
removeDetachedView(v, false);
transViewsById.removeAt(i);
i--;
}
}
}
}
/**
* Puts all views in the scrap heap into the supplied list.
*/
void reclaimScrapViews(List views) {
if (mViewTypeCount == 1) {
views.addAll(mCurrentScrap);
} else {
final int viewTypeCount = mViewTypeCount;
final ArrayList[] scrapViews = mScrapViews;
for (int i = 0; i < viewTypeCount; ++i) {
final ArrayList scrapPile = scrapViews[i];
views.addAll(scrapPile);
}
}
}
/**
* Updates the cache color hint of all known views.
*
* @param color The new cache color hint.
*/
void setCacheColorHint(int color) {
if (mViewTypeCount == 1) {
final ArrayList scrap = mCurrentScrap;
final int scrapCount = scrap.size();
for (int i = 0; i < scrapCount; i++) {
scrap.get(i).setDrawingCacheBackgroundColor(color);
}
} else {
final int typeCount = mViewTypeCount;
for (int i = 0; i < typeCount; i++) {
final ArrayList scrap = mScrapViews[i];
final int scrapCount = scrap.size();
for (int j = 0; j < scrapCount; j++) {
scrap.get(j).setDrawingCacheBackgroundColor(color);
}
}
}
// Just in case this is called during a layout pass
final View[] activeViews = mActiveViews;
final int count = activeViews.length;
for (int i = 0; i < count; ++i) {
final View victim = activeViews[i];
if (victim != null) {
victim.setDrawingCacheBackgroundColor(color);
}
}
}
private View retrieveFromScrap(ArrayList scrapViews, int position) {
final int size = scrapViews.size();
if (size > 0) {
// See if we still have a view for this position or ID.
// Traverse backwards to find the most recently used scrap view
for (int i = size - 1; i >= 0; i--) {
final View view = scrapViews.get(i);
final AbsListView.LayoutParams params =
(AbsListView.LayoutParams) view.getLayoutParams();
if (mAdapterHasStableIds) {
final long id = mAdapter.getItemId(position);
if (id == params.itemId) {
return scrapViews.remove(i);
}
} else if (params.scrappedFromPosition == position) {
final View scrap = scrapViews.remove(i);
clearScrapForRebind(scrap);
return scrap;
}
}
final View scrap = scrapViews.remove(size - 1);
clearScrapForRebind(scrap);
return scrap;
} else {
return null;
}
}
private void clearScrap(final ArrayList scrap) {
final int scrapCount = scrap.size();
for (int j = 0; j < scrapCount; j++) {
removeDetachedView(scrap.remove(scrapCount - 1 - j), false);
}
}
private void clearScrapForRebind(View view) {
view.clearAccessibilityFocus();
view.setAccessibilityDelegate(null);
view.resetSubtreeAutofillIds();
}
private void removeDetachedView(View child, boolean animate) {
child.setAccessibilityDelegate(null);
child.resetSubtreeAutofillIds();
AbsListView.this.removeDetachedView(child, animate);
}
}
/**
* Returns the height of the view for the specified position.
*
* @param position the item position
* @return view height in pixels
*/
int getHeightForPosition(int position) {
final int firstVisiblePosition = getFirstVisiblePosition();
final int childCount = getChildCount();
final int index = position - firstVisiblePosition;
if (index >= 0 && index < childCount) {
// Position is on-screen, use existing view.
final View view = getChildAt(index);
return view.getHeight();
} else {
// Position is off-screen, obtain & recycle view.
final View view = obtainView(position, mIsScrap);
view.measure(mWidthMeasureSpec, MeasureSpec.UNSPECIFIED);
final int height = view.getMeasuredHeight();
mRecycler.addScrapView(view, position);
return height;
}
}
/**
* Sets the selected item and positions the selection y pixels from the top edge
* of the ListView. (If in touch mode, the item will not be selected but it will
* still be positioned appropriately.)
*
* @param position Index (starting at 0) of the data item to be selected.
* @param y The distance from the top edge of the ListView (plus padding) that the
* item will be positioned.
*/
public void setSelectionFromTop(int position, int y) {
if (mAdapter == null) {
return;
}
if (!isInTouchMode()) {
position = lookForSelectablePosition(position, true);
if (position >= 0) {
setNextSelectedPositionInt(position);
}
} else {
mResurrectToPosition = position;
}
if (position >= 0) {
mLayoutMode = LAYOUT_SPECIFIC;
mSpecificTop = mListPadding.top + y;
if (mNeedSync) {
mSyncPosition = position;
mSyncRowId = mAdapter.getItemId(position);
}
if (mPositionScroller != null) {
mPositionScroller.stop();
}
requestLayout();
}
}
/** @hide */
@Override
protected void encodeProperties(@NonNull ViewHierarchyEncoder encoder) {
super.encodeProperties(encoder);
encoder.addProperty("drawing:cacheColorHint", getCacheColorHint());
encoder.addProperty("list:fastScrollEnabled", isFastScrollEnabled());
encoder.addProperty("list:scrollingCacheEnabled", isScrollingCacheEnabled());
encoder.addProperty("list:smoothScrollbarEnabled", isSmoothScrollbarEnabled());
encoder.addProperty("list:stackFromBottom", isStackFromBottom());
encoder.addProperty("list:textFilterEnabled", isTextFilterEnabled());
View selectedView = getSelectedView();
if (selectedView != null) {
encoder.addPropertyKey("selectedView");
selectedView.encode(encoder);
}
}
/**
* Abstract positon scroller used to handle smooth scrolling.
*/
static abstract class AbsPositionScroller {
public abstract void start(int position);
public abstract void start(int position, int boundPosition);
public abstract void startWithOffset(int position, int offset);
public abstract void startWithOffset(int position, int offset, int duration);
public abstract void stop();
}
/**
* Default position scroller that simulates a fling.
*/
class PositionScroller extends AbsPositionScroller implements Runnable {
private static final int SCROLL_DURATION = 200;
private static final int MOVE_DOWN_POS = 1;
private static final int MOVE_UP_POS = 2;
private static final int MOVE_DOWN_BOUND = 3;
private static final int MOVE_UP_BOUND = 4;
private static final int MOVE_OFFSET = 5;
private int mMode;
private int mTargetPos;
private int mBoundPos;
private int mLastSeenPos;
private int mScrollDuration;
private final int mExtraScroll;
private int mOffsetFromTop;
PositionScroller() {
mExtraScroll = ViewConfiguration.get(mContext).getScaledFadingEdgeLength();
}
@Override
public void start(final int position) {
stop();
if (mDataChanged) {
// Wait until we're back in a stable state to try this.
mPositionScrollAfterLayout = new Runnable() {
@Override public void run() {
start(position);
}
};
return;
}
final int childCount = getChildCount();
if (childCount == 0) {
// Can't scroll without children.
return;
}
final int firstPos = mFirstPosition;
final int lastPos = firstPos + childCount - 1;
int viewTravelCount;
int clampedPosition = Math.max(0, Math.min(getCount() - 1, position));
if (clampedPosition < firstPos) {
viewTravelCount = firstPos - clampedPosition + 1;
mMode = MOVE_UP_POS;
} else if (clampedPosition > lastPos) {
viewTravelCount = clampedPosition - lastPos + 1;
mMode = MOVE_DOWN_POS;
} else {
scrollToVisible(clampedPosition, INVALID_POSITION, SCROLL_DURATION);
return;
}
if (viewTravelCount > 0) {
mScrollDuration = SCROLL_DURATION / viewTravelCount;
} else {
mScrollDuration = SCROLL_DURATION;
}
mTargetPos = clampedPosition;
mBoundPos = INVALID_POSITION;
mLastSeenPos = INVALID_POSITION;
postOnAnimation(this);
}
@Override
public void start(final int position, final int boundPosition) {
stop();
if (boundPosition == INVALID_POSITION) {
start(position);
return;
}
if (mDataChanged) {
// Wait until we're back in a stable state to try this.
mPositionScrollAfterLayout = new Runnable() {
@Override public void run() {
start(position, boundPosition);
}
};
return;
}
final int childCount = getChildCount();
if (childCount == 0) {
// Can't scroll without children.
return;
}
final int firstPos = mFirstPosition;
final int lastPos = firstPos + childCount - 1;
int viewTravelCount;
int clampedPosition = Math.max(0, Math.min(getCount() - 1, position));
if (clampedPosition < firstPos) {
final int boundPosFromLast = lastPos - boundPosition;
if (boundPosFromLast < 1) {
// Moving would shift our bound position off the screen. Abort.
return;
}
final int posTravel = firstPos - clampedPosition + 1;
final int boundTravel = boundPosFromLast - 1;
if (boundTravel < posTravel) {
viewTravelCount = boundTravel;
mMode = MOVE_UP_BOUND;
} else {
viewTravelCount = posTravel;
mMode = MOVE_UP_POS;
}
} else if (clampedPosition > lastPos) {
final int boundPosFromFirst = boundPosition - firstPos;
if (boundPosFromFirst < 1) {
// Moving would shift our bound position off the screen. Abort.
return;
}
final int posTravel = clampedPosition - lastPos + 1;
final int boundTravel = boundPosFromFirst - 1;
if (boundTravel < posTravel) {
viewTravelCount = boundTravel;
mMode = MOVE_DOWN_BOUND;
} else {
viewTravelCount = posTravel;
mMode = MOVE_DOWN_POS;
}
} else {
scrollToVisible(clampedPosition, boundPosition, SCROLL_DURATION);
return;
}
if (viewTravelCount > 0) {
mScrollDuration = SCROLL_DURATION / viewTravelCount;
} else {
mScrollDuration = SCROLL_DURATION;
}
mTargetPos = clampedPosition;
mBoundPos = boundPosition;
mLastSeenPos = INVALID_POSITION;
postOnAnimation(this);
}
@Override
public void startWithOffset(int position, int offset) {
startWithOffset(position, offset, SCROLL_DURATION);
}
@Override
public void startWithOffset(final int position, int offset, final int duration) {
stop();
if (mDataChanged) {
// Wait until we're back in a stable state to try this.
final int postOffset = offset;
mPositionScrollAfterLayout = new Runnable() {
@Override public void run() {
startWithOffset(position, postOffset, duration);
}
};
return;
}
final int childCount = getChildCount();
if (childCount == 0) {
// Can't scroll without children.
return;
}
offset += getPaddingTop();
mTargetPos = Math.max(0, Math.min(getCount() - 1, position));
mOffsetFromTop = offset;
mBoundPos = INVALID_POSITION;
mLastSeenPos = INVALID_POSITION;
mMode = MOVE_OFFSET;
final int firstPos = mFirstPosition;
final int lastPos = firstPos + childCount - 1;
int viewTravelCount;
if (mTargetPos < firstPos) {
viewTravelCount = firstPos - mTargetPos;
} else if (mTargetPos > lastPos) {
viewTravelCount = mTargetPos - lastPos;
} else {
// On-screen, just scroll.
final int targetTop = getChildAt(mTargetPos - firstPos).getTop();
smoothScrollBy(targetTop - offset, duration, true, false);
return;
}
// Estimate how many screens we should travel
final float screenTravelCount = (float) viewTravelCount / childCount;
mScrollDuration = screenTravelCount < 1 ?
duration : (int) (duration / screenTravelCount);
mLastSeenPos = INVALID_POSITION;
postOnAnimation(this);
}
/**
* Scroll such that targetPos is in the visible padded region without scrolling
* boundPos out of view. Assumes targetPos is onscreen.
*/
private void scrollToVisible(int targetPos, int boundPos, int duration) {
final int firstPos = mFirstPosition;
final int childCount = getChildCount();
final int lastPos = firstPos + childCount - 1;
final int paddedTop = mListPadding.top;
final int paddedBottom = getHeight() - mListPadding.bottom;
if (targetPos < firstPos || targetPos > lastPos) {
Log.w(TAG, "scrollToVisible called with targetPos " + targetPos +
" not visible [" + firstPos + ", " + lastPos + "]");
}
if (boundPos < firstPos || boundPos > lastPos) {
// boundPos doesn't matter, it's already offscreen.
boundPos = INVALID_POSITION;
}
final View targetChild = getChildAt(targetPos - firstPos);
final int targetTop = targetChild.getTop();
final int targetBottom = targetChild.getBottom();
int scrollBy = 0;
if (targetBottom > paddedBottom) {
scrollBy = targetBottom - paddedBottom;
}
if (targetTop < paddedTop) {
scrollBy = targetTop - paddedTop;
}
if (scrollBy == 0) {
return;
}
if (boundPos >= 0) {
final View boundChild = getChildAt(boundPos - firstPos);
final int boundTop = boundChild.getTop();
final int boundBottom = boundChild.getBottom();
final int absScroll = Math.abs(scrollBy);
if (scrollBy < 0 && boundBottom + absScroll > paddedBottom) {
// Don't scroll the bound view off the bottom of the screen.
scrollBy = Math.max(0, boundBottom - paddedBottom);
} else if (scrollBy > 0 && boundTop - absScroll < paddedTop) {
// Don't scroll the bound view off the top of the screen.
scrollBy = Math.min(0, boundTop - paddedTop);
}
}
smoothScrollBy(scrollBy, duration);
}
@Override
public void stop() {
removeCallbacks(this);
}
@Override
public void run() {
final int listHeight = getHeight();
final int firstPos = mFirstPosition;
switch (mMode) {
case MOVE_DOWN_POS: {
final int lastViewIndex = getChildCount() - 1;
final int lastPos = firstPos + lastViewIndex;
if (lastViewIndex < 0) {
return;
}
if (lastPos == mLastSeenPos) {
// No new views, let things keep going.
postOnAnimation(this);
return;
}
final View lastView = getChildAt(lastViewIndex);
final int lastViewHeight = lastView.getHeight();
final int lastViewTop = lastView.getTop();
final int lastViewPixelsShowing = listHeight - lastViewTop;
final int extraScroll = lastPos < mItemCount - 1 ?
Math.max(mListPadding.bottom, mExtraScroll) : mListPadding.bottom;
final int scrollBy = lastViewHeight - lastViewPixelsShowing + extraScroll;
smoothScrollBy(scrollBy, mScrollDuration, true, lastPos < mTargetPos);
mLastSeenPos = lastPos;
if (lastPos < mTargetPos) {
postOnAnimation(this);
}
break;
}
case MOVE_DOWN_BOUND: {
final int nextViewIndex = 1;
final int childCount = getChildCount();
if (firstPos == mBoundPos || childCount <= nextViewIndex
|| firstPos + childCount >= mItemCount) {
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
return;
}
final int nextPos = firstPos + nextViewIndex;
if (nextPos == mLastSeenPos) {
// No new views, let things keep going.
postOnAnimation(this);
return;
}
final View nextView = getChildAt(nextViewIndex);
final int nextViewHeight = nextView.getHeight();
final int nextViewTop = nextView.getTop();
final int extraScroll = Math.max(mListPadding.bottom, mExtraScroll);
if (nextPos < mBoundPos) {
smoothScrollBy(Math.max(0, nextViewHeight + nextViewTop - extraScroll),
mScrollDuration, true, true);
mLastSeenPos = nextPos;
postOnAnimation(this);
} else {
if (nextViewTop > extraScroll) {
smoothScrollBy(nextViewTop - extraScroll, mScrollDuration, true, false);
} else {
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
}
}
break;
}
case MOVE_UP_POS: {
if (firstPos == mLastSeenPos) {
// No new views, let things keep going.
postOnAnimation(this);
return;
}
final View firstView = getChildAt(0);
if (firstView == null) {
return;
}
final int firstViewTop = firstView.getTop();
final int extraScroll = firstPos > 0 ?
Math.max(mExtraScroll, mListPadding.top) : mListPadding.top;
smoothScrollBy(firstViewTop - extraScroll, mScrollDuration, true,
firstPos > mTargetPos);
mLastSeenPos = firstPos;
if (firstPos > mTargetPos) {
postOnAnimation(this);
}
break;
}
case MOVE_UP_BOUND: {
final int lastViewIndex = getChildCount() - 2;
if (lastViewIndex < 0) {
return;
}
final int lastPos = firstPos + lastViewIndex;
if (lastPos == mLastSeenPos) {
// No new views, let things keep going.
postOnAnimation(this);
return;
}
final View lastView = getChildAt(lastViewIndex);
final int lastViewHeight = lastView.getHeight();
final int lastViewTop = lastView.getTop();
final int lastViewPixelsShowing = listHeight - lastViewTop;
final int extraScroll = Math.max(mListPadding.top, mExtraScroll);
mLastSeenPos = lastPos;
if (lastPos > mBoundPos) {
smoothScrollBy(-(lastViewPixelsShowing - extraScroll), mScrollDuration, true,
true);
postOnAnimation(this);
} else {
final int bottom = listHeight - extraScroll;
final int lastViewBottom = lastViewTop + lastViewHeight;
if (bottom > lastViewBottom) {
smoothScrollBy(-(bottom - lastViewBottom), mScrollDuration, true, false);
} else {
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
}
}
break;
}
case MOVE_OFFSET: {
if (mLastSeenPos == firstPos) {
// No new views, let things keep going.
postOnAnimation(this);
return;
}
mLastSeenPos = firstPos;
final int childCount = getChildCount();
if (childCount <= 0) {
return;
}
final int position = mTargetPos;
final int lastPos = firstPos + childCount - 1;
// Account for the visible "portion" of the first / last child when we estimate
// how many screens we should travel to reach our target
final View firstChild = getChildAt(0);
final int firstChildHeight = firstChild.getHeight();
final View lastChild = getChildAt(childCount - 1);
final int lastChildHeight = lastChild.getHeight();
final float firstPositionVisiblePart = (firstChildHeight == 0.0f) ? 1.0f
: (float) (firstChildHeight + firstChild.getTop()) / firstChildHeight;
final float lastPositionVisiblePart = (lastChildHeight == 0.0f) ? 1.0f
: (float) (lastChildHeight + getHeight() - lastChild.getBottom())
/ lastChildHeight;
float viewTravelCount = 0;
if (position < firstPos) {
viewTravelCount = firstPos - position + (1.0f - firstPositionVisiblePart) + 1;
} else if (position > lastPos) {
viewTravelCount = position - lastPos + (1.0f - lastPositionVisiblePart);
}
// Estimate how many screens we should travel
final float screenTravelCount = viewTravelCount / childCount;
final float modifier = Math.min(Math.abs(screenTravelCount), 1.f);
if (position < firstPos) {
final int distance = (int) (-getHeight() * modifier);
final int duration = (int) (mScrollDuration * modifier);
smoothScrollBy(distance, duration, true, true);
postOnAnimation(this);
} else if (position > lastPos) {
final int distance = (int) (getHeight() * modifier);
final int duration = (int) (mScrollDuration * modifier);
smoothScrollBy(distance, duration, true, true);
postOnAnimation(this);
} else {
// On-screen, just scroll.
final int targetTop = getChildAt(position - firstPos).getTop();
final int distance = targetTop - mOffsetFromTop;
final int duration = (int) (mScrollDuration *
((float) Math.abs(distance) / getHeight()));
smoothScrollBy(distance, duration, true, false);
}
break;
}
default:
break;
}
}
}
}