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/*
* Copyright (C) 2008 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.view;
import static com.android.internal.util.FrameworkStatsLog.TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__DEEP_PRESS;
import static com.android.internal.util.FrameworkStatsLog.TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__DOUBLE_TAP;
import static com.android.internal.util.FrameworkStatsLog.TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__LONG_PRESS;
import static com.android.internal.util.FrameworkStatsLog.TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__SCROLL;
import static com.android.internal.util.FrameworkStatsLog.TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__SINGLE_TAP;
import static com.android.internal.util.FrameworkStatsLog.TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__UNKNOWN_CLASSIFICATION;
import android.annotation.UiContext;
import android.compat.annotation.UnsupportedAppUsage;
import android.content.Context;
import android.os.Build;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.os.StrictMode;
import android.os.SystemClock;
import com.android.internal.util.FrameworkStatsLog;
/**
* Detects various gestures and events using the supplied {@link MotionEvent}s.
* The {@link OnGestureListener} callback will notify users when a particular
* motion event has occurred. This class should only be used with {@link MotionEvent}s
* reported via touch (don't use for trackball events).
*
* To use this class:
*
* - Create an instance of the {@code GestureDetector} for your {@link View}
*
- In the {@link View#onTouchEvent(MotionEvent)} method ensure you call
* {@link #onTouchEvent(MotionEvent)}. The methods defined in your callback
* will be executed when the events occur.
*
- If listening for {@link OnContextClickListener#onContextClick(MotionEvent)}
* you must call {@link #onGenericMotionEvent(MotionEvent)}
* in {@link View#onGenericMotionEvent(MotionEvent)}.
*
*/
public class GestureDetector {
/**
* The listener that is used to notify when gestures occur.
* If you want to listen for all the different gestures then implement
* this interface. If you only want to listen for a subset it might
* be easier to extend {@link SimpleOnGestureListener}.
*/
public interface OnGestureListener {
/**
* Notified when a tap occurs with the down {@link MotionEvent}
* that triggered it. This will be triggered immediately for
* every down event. All other events should be preceded by this.
*
* @param e The down motion event.
*/
boolean onDown(MotionEvent e);
/**
* The user has performed a down {@link MotionEvent} and not performed
* a move or up yet. This event is commonly used to provide visual
* feedback to the user to let them know that their action has been
* recognized i.e. highlight an element.
*
* @param e The down motion event
*/
void onShowPress(MotionEvent e);
/**
* Notified when a tap occurs with the up {@link MotionEvent}
* that triggered it.
*
* @param e The up motion event that completed the first tap
* @return true if the event is consumed, else false
*/
boolean onSingleTapUp(MotionEvent e);
/**
* Notified when a scroll occurs with the initial on down {@link MotionEvent} and the
* current move {@link MotionEvent}. The distance in x and y is also supplied for
* convenience.
*
* @param e1 The first down motion event that started the scrolling.
* @param e2 The move motion event that triggered the current onScroll.
* @param distanceX The distance along the X axis that has been scrolled since the last
* call to onScroll. This is NOT the distance between {@code e1}
* and {@code e2}.
* @param distanceY The distance along the Y axis that has been scrolled since the last
* call to onScroll. This is NOT the distance between {@code e1}
* and {@code e2}.
* @return true if the event is consumed, else false
*/
boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY);
/**
* Notified when a long press occurs with the initial on down {@link MotionEvent}
* that trigged it.
*
* @param e The initial on down motion event that started the longpress.
*/
void onLongPress(MotionEvent e);
/**
* Notified of a fling event when it occurs with the initial on down {@link MotionEvent}
* and the matching up {@link MotionEvent}. The calculated velocity is supplied along
* the x and y axis in pixels per second.
*
* @param e1 The first down motion event that started the fling.
* @param e2 The move motion event that triggered the current onFling.
* @param velocityX The velocity of this fling measured in pixels per second
* along the x axis.
* @param velocityY The velocity of this fling measured in pixels per second
* along the y axis.
* @return true if the event is consumed, else false
*/
boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY);
}
/**
* The listener that is used to notify when a double-tap or a confirmed
* single-tap occur.
*/
public interface OnDoubleTapListener {
/**
* Notified when a single-tap occurs.
*
* Unlike {@link OnGestureListener#onSingleTapUp(MotionEvent)}, this
* will only be called after the detector is confident that the user's
* first tap is not followed by a second tap leading to a double-tap
* gesture.
*
* @param e The down motion event of the single-tap.
* @return true if the event is consumed, else false
*/
boolean onSingleTapConfirmed(MotionEvent e);
/**
* Notified when a double-tap occurs. Triggered on the down event of second tap.
*
* @param e The down motion event of the first tap of the double-tap.
* @return true if the event is consumed, else false
*/
boolean onDoubleTap(MotionEvent e);
/**
* Notified when an event within a double-tap gesture occurs, including
* the down, move, and up events.
*
* @param e The motion event that occurred during the double-tap gesture.
* @return true if the event is consumed, else false
*/
boolean onDoubleTapEvent(MotionEvent e);
}
/**
* The listener that is used to notify when a context click occurs. When listening for a
* context click ensure that you call {@link #onGenericMotionEvent(MotionEvent)} in
* {@link View#onGenericMotionEvent(MotionEvent)}.
*/
public interface OnContextClickListener {
/**
* Notified when a context click occurs.
*
* @param e The motion event that occurred during the context click.
* @return true if the event is consumed, else false
*/
boolean onContextClick(MotionEvent e);
}
/**
* A convenience class to extend when you only want to listen for a subset
* of all the gestures. This implements all methods in the
* {@link OnGestureListener}, {@link OnDoubleTapListener}, and {@link OnContextClickListener}
* but does nothing and return {@code false} for all applicable methods.
*/
public static class SimpleOnGestureListener implements OnGestureListener, OnDoubleTapListener,
OnContextClickListener {
public boolean onSingleTapUp(MotionEvent e) {
return false;
}
public void onLongPress(MotionEvent e) {
}
public boolean onScroll(MotionEvent e1, MotionEvent e2,
float distanceX, float distanceY) {
return false;
}
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
return false;
}
public void onShowPress(MotionEvent e) {
}
public boolean onDown(MotionEvent e) {
return false;
}
public boolean onDoubleTap(MotionEvent e) {
return false;
}
public boolean onDoubleTapEvent(MotionEvent e) {
return false;
}
public boolean onSingleTapConfirmed(MotionEvent e) {
return false;
}
public boolean onContextClick(MotionEvent e) {
return false;
}
}
private static final String TAG = GestureDetector.class.getSimpleName();
@UnsupportedAppUsage
private int mTouchSlopSquare;
private int mDoubleTapTouchSlopSquare;
private int mDoubleTapSlopSquare;
private float mAmbiguousGestureMultiplier;
@UnsupportedAppUsage
private int mMinimumFlingVelocity;
private int mMaximumFlingVelocity;
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P)
private static final int LONGPRESS_TIMEOUT = ViewConfiguration.getLongPressTimeout();
private static final int TAP_TIMEOUT = ViewConfiguration.getTapTimeout();
private static final int DOUBLE_TAP_TIMEOUT = ViewConfiguration.getDoubleTapTimeout();
private static final int DOUBLE_TAP_MIN_TIME = ViewConfiguration.getDoubleTapMinTime();
// constants for Message.what used by GestureHandler below
private static final int SHOW_PRESS = 1;
private static final int LONG_PRESS = 2;
private static final int TAP = 3;
private final Handler mHandler;
@UnsupportedAppUsage
private final OnGestureListener mListener;
private OnDoubleTapListener mDoubleTapListener;
private OnContextClickListener mContextClickListener;
private boolean mStillDown;
private boolean mDeferConfirmSingleTap;
private boolean mInLongPress;
private boolean mInContextClick;
@UnsupportedAppUsage
private boolean mAlwaysInTapRegion;
private boolean mAlwaysInBiggerTapRegion;
private boolean mIgnoreNextUpEvent;
// Whether a classification has been recorded by statsd for the current event stream. Reset on
// ACTION_DOWN.
private boolean mHasRecordedClassification;
private MotionEvent mCurrentDownEvent;
private MotionEvent mCurrentMotionEvent;
private MotionEvent mPreviousUpEvent;
/**
* True when the user is still touching for the second tap (down, move, and
* up events). Can only be true if there is a double tap listener attached.
*/
private boolean mIsDoubleTapping;
private float mLastFocusX;
private float mLastFocusY;
private float mDownFocusX;
private float mDownFocusY;
private boolean mIsLongpressEnabled;
/**
* Determines speed during touch scrolling
*/
private VelocityTracker mVelocityTracker;
/**
* Consistency verifier for debugging purposes.
*/
private final InputEventConsistencyVerifier mInputEventConsistencyVerifier =
InputEventConsistencyVerifier.isInstrumentationEnabled() ?
new InputEventConsistencyVerifier(this, 0) : null;
private class GestureHandler extends Handler {
GestureHandler() {
super();
}
GestureHandler(Handler handler) {
super(handler.getLooper());
}
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case SHOW_PRESS:
mListener.onShowPress(mCurrentDownEvent);
break;
case LONG_PRESS:
recordGestureClassification(msg.arg1);
dispatchLongPress();
break;
case TAP:
// If the user's finger is still down, do not count it as a tap
if (mDoubleTapListener != null) {
if (!mStillDown) {
recordGestureClassification(
TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__SINGLE_TAP);
mDoubleTapListener.onSingleTapConfirmed(mCurrentDownEvent);
} else {
mDeferConfirmSingleTap = true;
}
}
break;
default:
throw new RuntimeException("Unknown message " + msg); //never
}
}
}
/**
* Creates a GestureDetector with the supplied listener.
* This variant of the constructor should be used from a non-UI thread
* (as it allows specifying the Handler).
*
* @param listener the listener invoked for all the callbacks, this must
* not be null.
* @param handler the handler to use
*
* @throws NullPointerException if either {@code listener} or
* {@code handler} is null.
*
* @deprecated Use {@link #GestureDetector(android.content.Context,
* android.view.GestureDetector.OnGestureListener, android.os.Handler)} instead.
*/
@Deprecated
public GestureDetector(OnGestureListener listener, Handler handler) {
this(null, listener, handler);
}
/**
* Creates a GestureDetector with the supplied listener.
* You may only use this constructor from a UI thread (this is the usual situation).
* @see android.os.Handler#Handler()
*
* @param listener the listener invoked for all the callbacks, this must
* not be null.
*
* @throws NullPointerException if {@code listener} is null.
*
* @deprecated Use {@link #GestureDetector(android.content.Context,
* android.view.GestureDetector.OnGestureListener)} instead.
*/
@Deprecated
public GestureDetector(OnGestureListener listener) {
this(null, listener, null);
}
/**
* Creates a GestureDetector with the supplied listener.
* You may only use this constructor from a {@link android.os.Looper} thread.
* @see android.os.Handler#Handler()
*
* @param context An {@link android.app.Activity} or a {@link Context} created from
* {@link Context#createWindowContext(int, Bundle)}
* @param listener the listener invoked for all the callbacks, this must
* not be null. If the listener implements the {@link OnDoubleTapListener} or
* {@link OnContextClickListener} then it will also be set as the listener for
* these callbacks (for example when using the {@link SimpleOnGestureListener}).
*
* @throws NullPointerException if {@code listener} is null.
*/
// TODO(b/182007470): Use @ConfigurationContext instead
public GestureDetector(@UiContext Context context, OnGestureListener listener) {
this(context, listener, null);
}
/**
* Creates a GestureDetector with the supplied listener that runs deferred events on the
* thread associated with the supplied {@link android.os.Handler}.
* @see android.os.Handler#Handler()
*
* @param context An {@link android.app.Activity} or a {@link Context} created from
* {@link Context#createWindowContext(int, Bundle)}
* @param listener the listener invoked for all the callbacks, this must
* not be null. If the listener implements the {@link OnDoubleTapListener} or
* {@link OnContextClickListener} then it will also be set as the listener for
* these callbacks (for example when using the {@link SimpleOnGestureListener}).
* @param handler the handler to use for running deferred listener events.
*
* @throws NullPointerException if {@code listener} is null.
*/
public GestureDetector(@UiContext Context context, OnGestureListener listener,
Handler handler) {
if (handler != null) {
mHandler = new GestureHandler(handler);
} else {
mHandler = new GestureHandler();
}
mListener = listener;
if (listener instanceof OnDoubleTapListener) {
setOnDoubleTapListener((OnDoubleTapListener) listener);
}
if (listener instanceof OnContextClickListener) {
setContextClickListener((OnContextClickListener) listener);
}
init(context);
}
/**
* Creates a GestureDetector with the supplied listener that runs deferred events on the
* thread associated with the supplied {@link android.os.Handler}.
* @see android.os.Handler#Handler()
*
* @param context An {@link android.app.Activity} or a {@link Context} created from
* {@link Context#createWindowContext(int, Bundle)}
* @param listener the listener invoked for all the callbacks, this must
* not be null.
* @param handler the handler to use for running deferred listener events.
* @param unused currently not used.
*
* @throws NullPointerException if {@code listener} is null.
*/
public GestureDetector(@UiContext Context context, OnGestureListener listener, Handler handler,
boolean unused) {
this(context, listener, handler);
}
private void init(@UiContext Context context) {
if (mListener == null) {
throw new NullPointerException("OnGestureListener must not be null");
}
mIsLongpressEnabled = true;
// Fallback to support pre-donuts releases
int touchSlop, doubleTapSlop, doubleTapTouchSlop;
if (context == null) {
//noinspection deprecation
touchSlop = ViewConfiguration.getTouchSlop();
doubleTapTouchSlop = touchSlop; // Hack rather than adding a hidden method for this
doubleTapSlop = ViewConfiguration.getDoubleTapSlop();
//noinspection deprecation
mMinimumFlingVelocity = ViewConfiguration.getMinimumFlingVelocity();
mMaximumFlingVelocity = ViewConfiguration.getMaximumFlingVelocity();
mAmbiguousGestureMultiplier = ViewConfiguration.getAmbiguousGestureMultiplier();
} else {
StrictMode.assertConfigurationContext(context, "GestureDetector#init");
final ViewConfiguration configuration = ViewConfiguration.get(context);
touchSlop = configuration.getScaledTouchSlop();
doubleTapTouchSlop = configuration.getScaledDoubleTapTouchSlop();
doubleTapSlop = configuration.getScaledDoubleTapSlop();
mMinimumFlingVelocity = configuration.getScaledMinimumFlingVelocity();
mMaximumFlingVelocity = configuration.getScaledMaximumFlingVelocity();
mAmbiguousGestureMultiplier = configuration.getScaledAmbiguousGestureMultiplier();
}
mTouchSlopSquare = touchSlop * touchSlop;
mDoubleTapTouchSlopSquare = doubleTapTouchSlop * doubleTapTouchSlop;
mDoubleTapSlopSquare = doubleTapSlop * doubleTapSlop;
}
/**
* Sets the listener which will be called for double-tap and related
* gestures.
*
* @param onDoubleTapListener the listener invoked for all the callbacks, or
* null to stop listening for double-tap gestures.
*/
public void setOnDoubleTapListener(OnDoubleTapListener onDoubleTapListener) {
mDoubleTapListener = onDoubleTapListener;
}
/**
* Sets the listener which will be called for context clicks.
*
* @param onContextClickListener the listener invoked for all the callbacks, or null to stop
* listening for context clicks.
*/
public void setContextClickListener(OnContextClickListener onContextClickListener) {
mContextClickListener = onContextClickListener;
}
/**
* Set whether longpress is enabled, if this is enabled when a user
* presses and holds down you get a longpress event and nothing further.
* If it's disabled the user can press and hold down and then later
* moved their finger and you will get scroll events. By default
* longpress is enabled.
*
* @param isLongpressEnabled whether longpress should be enabled.
*/
public void setIsLongpressEnabled(boolean isLongpressEnabled) {
mIsLongpressEnabled = isLongpressEnabled;
}
/**
* @return true if longpress is enabled, else false.
*/
public boolean isLongpressEnabled() {
return mIsLongpressEnabled;
}
/**
* Analyzes the given motion event and if applicable triggers the
* appropriate callbacks on the {@link OnGestureListener} supplied.
*
* @param ev The current motion event.
* @return true if the {@link OnGestureListener} consumed the event,
* else false.
*/
public boolean onTouchEvent(MotionEvent ev) {
if (mInputEventConsistencyVerifier != null) {
mInputEventConsistencyVerifier.onTouchEvent(ev, 0);
}
final int action = ev.getAction();
if (mCurrentMotionEvent != null) {
mCurrentMotionEvent.recycle();
}
mCurrentMotionEvent = MotionEvent.obtain(ev);
if (mVelocityTracker == null) {
mVelocityTracker = VelocityTracker.obtain();
}
mVelocityTracker.addMovement(ev);
final boolean pointerUp =
(action & MotionEvent.ACTION_MASK) == MotionEvent.ACTION_POINTER_UP;
final int skipIndex = pointerUp ? ev.getActionIndex() : -1;
final boolean isGeneratedGesture =
(ev.getFlags() & MotionEvent.FLAG_IS_GENERATED_GESTURE) != 0;
// Determine focal point
float sumX = 0, sumY = 0;
final int count = ev.getPointerCount();
for (int i = 0; i < count; i++) {
if (skipIndex == i) continue;
sumX += ev.getX(i);
sumY += ev.getY(i);
}
final int div = pointerUp ? count - 1 : count;
final float focusX = sumX / div;
final float focusY = sumY / div;
boolean handled = false;
switch (action & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_POINTER_DOWN:
mDownFocusX = mLastFocusX = focusX;
mDownFocusY = mLastFocusY = focusY;
// Cancel long press and taps
cancelTaps();
break;
case MotionEvent.ACTION_POINTER_UP:
mDownFocusX = mLastFocusX = focusX;
mDownFocusY = mLastFocusY = focusY;
// Check the dot product of current velocities.
// If the pointer that left was opposing another velocity vector, clear.
mVelocityTracker.computeCurrentVelocity(1000, mMaximumFlingVelocity);
final int upIndex = ev.getActionIndex();
final int id1 = ev.getPointerId(upIndex);
final float x1 = mVelocityTracker.getXVelocity(id1);
final float y1 = mVelocityTracker.getYVelocity(id1);
for (int i = 0; i < count; i++) {
if (i == upIndex) continue;
final int id2 = ev.getPointerId(i);
final float x = x1 * mVelocityTracker.getXVelocity(id2);
final float y = y1 * mVelocityTracker.getYVelocity(id2);
final float dot = x + y;
if (dot < 0) {
mVelocityTracker.clear();
break;
}
}
break;
case MotionEvent.ACTION_DOWN:
if (mDoubleTapListener != null) {
boolean hadTapMessage = mHandler.hasMessages(TAP);
if (hadTapMessage) mHandler.removeMessages(TAP);
if ((mCurrentDownEvent != null) && (mPreviousUpEvent != null)
&& hadTapMessage
&& isConsideredDoubleTap(mCurrentDownEvent, mPreviousUpEvent, ev)) {
// This is a second tap
mIsDoubleTapping = true;
recordGestureClassification(
TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__DOUBLE_TAP);
// Give a callback with the first tap of the double-tap
handled |= mDoubleTapListener.onDoubleTap(mCurrentDownEvent);
// Give a callback with down event of the double-tap
handled |= mDoubleTapListener.onDoubleTapEvent(ev);
} else {
// This is a first tap
mHandler.sendEmptyMessageDelayed(TAP, DOUBLE_TAP_TIMEOUT);
}
}
mDownFocusX = mLastFocusX = focusX;
mDownFocusY = mLastFocusY = focusY;
if (mCurrentDownEvent != null) {
mCurrentDownEvent.recycle();
}
mCurrentDownEvent = MotionEvent.obtain(ev);
mAlwaysInTapRegion = true;
mAlwaysInBiggerTapRegion = true;
mStillDown = true;
mInLongPress = false;
mDeferConfirmSingleTap = false;
mHasRecordedClassification = false;
if (mIsLongpressEnabled) {
mHandler.removeMessages(LONG_PRESS);
mHandler.sendMessageAtTime(
mHandler.obtainMessage(
LONG_PRESS,
TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__LONG_PRESS,
0 /* arg2 */),
mCurrentDownEvent.getDownTime()
+ ViewConfiguration.getLongPressTimeout());
}
mHandler.sendEmptyMessageAtTime(SHOW_PRESS,
mCurrentDownEvent.getDownTime() + TAP_TIMEOUT);
handled |= mListener.onDown(ev);
break;
case MotionEvent.ACTION_MOVE:
if (mInLongPress || mInContextClick) {
break;
}
final int motionClassification = ev.getClassification();
final boolean hasPendingLongPress = mHandler.hasMessages(LONG_PRESS);
final float scrollX = mLastFocusX - focusX;
final float scrollY = mLastFocusY - focusY;
if (mIsDoubleTapping) {
// Give the move events of the double-tap
recordGestureClassification(
TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__DOUBLE_TAP);
handled |= mDoubleTapListener.onDoubleTapEvent(ev);
} else if (mAlwaysInTapRegion) {
final int deltaX = (int) (focusX - mDownFocusX);
final int deltaY = (int) (focusY - mDownFocusY);
int distance = (deltaX * deltaX) + (deltaY * deltaY);
int slopSquare = isGeneratedGesture ? 0 : mTouchSlopSquare;
final boolean ambiguousGesture =
motionClassification == MotionEvent.CLASSIFICATION_AMBIGUOUS_GESTURE;
final boolean shouldInhibitDefaultAction =
hasPendingLongPress && ambiguousGesture;
if (shouldInhibitDefaultAction) {
// Inhibit default long press
if (distance > slopSquare) {
// The default action here is to remove long press. But if the touch
// slop below gets increased, and we never exceed the modified touch
// slop while still receiving AMBIGUOUS_GESTURE, we risk that *nothing*
// will happen in response to user input. To prevent this,
// reschedule long press with a modified timeout.
mHandler.removeMessages(LONG_PRESS);
final long longPressTimeout = ViewConfiguration.getLongPressTimeout();
mHandler.sendMessageAtTime(
mHandler.obtainMessage(
LONG_PRESS,
TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__LONG_PRESS,
0 /* arg2 */),
ev.getDownTime()
+ (long) (longPressTimeout * mAmbiguousGestureMultiplier));
}
// Inhibit default scroll. If a gesture is ambiguous, we prevent scroll
// until the gesture is resolved.
// However, for safety, simply increase the touch slop in case the
// classification is erroneous. Since the value is squared, multiply twice.
slopSquare *= mAmbiguousGestureMultiplier * mAmbiguousGestureMultiplier;
}
if (distance > slopSquare) {
recordGestureClassification(
TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__SCROLL);
handled = mListener.onScroll(mCurrentDownEvent, ev, scrollX, scrollY);
mLastFocusX = focusX;
mLastFocusY = focusY;
mAlwaysInTapRegion = false;
mHandler.removeMessages(TAP);
mHandler.removeMessages(SHOW_PRESS);
mHandler.removeMessages(LONG_PRESS);
}
int doubleTapSlopSquare = isGeneratedGesture ? 0 : mDoubleTapTouchSlopSquare;
if (distance > doubleTapSlopSquare) {
mAlwaysInBiggerTapRegion = false;
}
} else if ((Math.abs(scrollX) >= 1) || (Math.abs(scrollY) >= 1)) {
recordGestureClassification(TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__SCROLL);
handled = mListener.onScroll(mCurrentDownEvent, ev, scrollX, scrollY);
mLastFocusX = focusX;
mLastFocusY = focusY;
}
final boolean deepPress =
motionClassification == MotionEvent.CLASSIFICATION_DEEP_PRESS;
if (deepPress && hasPendingLongPress) {
mHandler.removeMessages(LONG_PRESS);
mHandler.sendMessage(
mHandler.obtainMessage(
LONG_PRESS,
TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__DEEP_PRESS,
0 /* arg2 */));
}
break;
case MotionEvent.ACTION_UP:
mStillDown = false;
MotionEvent currentUpEvent = MotionEvent.obtain(ev);
if (mIsDoubleTapping) {
// Finally, give the up event of the double-tap
recordGestureClassification(
TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__DOUBLE_TAP);
handled |= mDoubleTapListener.onDoubleTapEvent(ev);
} else if (mInLongPress) {
mHandler.removeMessages(TAP);
mInLongPress = false;
} else if (mAlwaysInTapRegion && !mIgnoreNextUpEvent) {
recordGestureClassification(
TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__SINGLE_TAP);
handled = mListener.onSingleTapUp(ev);
if (mDeferConfirmSingleTap && mDoubleTapListener != null) {
mDoubleTapListener.onSingleTapConfirmed(ev);
}
} else if (!mIgnoreNextUpEvent) {
// A fling must travel the minimum tap distance
final VelocityTracker velocityTracker = mVelocityTracker;
final int pointerId = ev.getPointerId(0);
velocityTracker.computeCurrentVelocity(1000, mMaximumFlingVelocity);
final float velocityY = velocityTracker.getYVelocity(pointerId);
final float velocityX = velocityTracker.getXVelocity(pointerId);
if ((Math.abs(velocityY) > mMinimumFlingVelocity)
|| (Math.abs(velocityX) > mMinimumFlingVelocity)) {
handled = mListener.onFling(mCurrentDownEvent, ev, velocityX, velocityY);
}
}
if (mPreviousUpEvent != null) {
mPreviousUpEvent.recycle();
}
// Hold the event we obtained above - listeners may have changed the original.
mPreviousUpEvent = currentUpEvent;
if (mVelocityTracker != null) {
// This may have been cleared when we called out to the
// application above.
mVelocityTracker.recycle();
mVelocityTracker = null;
}
mIsDoubleTapping = false;
mDeferConfirmSingleTap = false;
mIgnoreNextUpEvent = false;
mHandler.removeMessages(SHOW_PRESS);
mHandler.removeMessages(LONG_PRESS);
break;
case MotionEvent.ACTION_CANCEL:
cancel();
break;
}
if (!handled && mInputEventConsistencyVerifier != null) {
mInputEventConsistencyVerifier.onUnhandledEvent(ev, 0);
}
return handled;
}
/**
* Analyzes the given generic motion event and if applicable triggers the
* appropriate callbacks on the {@link OnGestureListener} supplied.
*
* @param ev The current motion event.
* @return true if the {@link OnGestureListener} consumed the event,
* else false.
*/
public boolean onGenericMotionEvent(MotionEvent ev) {
if (mInputEventConsistencyVerifier != null) {
mInputEventConsistencyVerifier.onGenericMotionEvent(ev, 0);
}
final int actionButton = ev.getActionButton();
switch (ev.getActionMasked()) {
case MotionEvent.ACTION_BUTTON_PRESS:
if (mContextClickListener != null && !mInContextClick && !mInLongPress
&& (actionButton == MotionEvent.BUTTON_STYLUS_PRIMARY
|| actionButton == MotionEvent.BUTTON_SECONDARY)) {
if (mContextClickListener.onContextClick(ev)) {
mInContextClick = true;
mHandler.removeMessages(LONG_PRESS);
mHandler.removeMessages(TAP);
return true;
}
}
break;
case MotionEvent.ACTION_BUTTON_RELEASE:
if (mInContextClick && (actionButton == MotionEvent.BUTTON_STYLUS_PRIMARY
|| actionButton == MotionEvent.BUTTON_SECONDARY)) {
mInContextClick = false;
mIgnoreNextUpEvent = true;
}
break;
}
return false;
}
private void cancel() {
mHandler.removeMessages(SHOW_PRESS);
mHandler.removeMessages(LONG_PRESS);
mHandler.removeMessages(TAP);
mVelocityTracker.recycle();
mVelocityTracker = null;
mIsDoubleTapping = false;
mStillDown = false;
mAlwaysInTapRegion = false;
mAlwaysInBiggerTapRegion = false;
mDeferConfirmSingleTap = false;
mInLongPress = false;
mInContextClick = false;
mIgnoreNextUpEvent = false;
}
private void cancelTaps() {
mHandler.removeMessages(SHOW_PRESS);
mHandler.removeMessages(LONG_PRESS);
mHandler.removeMessages(TAP);
mIsDoubleTapping = false;
mAlwaysInTapRegion = false;
mAlwaysInBiggerTapRegion = false;
mDeferConfirmSingleTap = false;
mInLongPress = false;
mInContextClick = false;
mIgnoreNextUpEvent = false;
}
private boolean isConsideredDoubleTap(MotionEvent firstDown, MotionEvent firstUp,
MotionEvent secondDown) {
if (!mAlwaysInBiggerTapRegion) {
return false;
}
final long deltaTime = secondDown.getEventTime() - firstUp.getEventTime();
if (deltaTime > DOUBLE_TAP_TIMEOUT || deltaTime < DOUBLE_TAP_MIN_TIME) {
return false;
}
int deltaX = (int) firstDown.getX() - (int) secondDown.getX();
int deltaY = (int) firstDown.getY() - (int) secondDown.getY();
final boolean isGeneratedGesture =
(firstDown.getFlags() & MotionEvent.FLAG_IS_GENERATED_GESTURE) != 0;
int slopSquare = isGeneratedGesture ? 0 : mDoubleTapSlopSquare;
return (deltaX * deltaX + deltaY * deltaY < slopSquare);
}
private void dispatchLongPress() {
mHandler.removeMessages(TAP);
mDeferConfirmSingleTap = false;
mInLongPress = true;
mListener.onLongPress(mCurrentDownEvent);
}
private void recordGestureClassification(int classification) {
if (mHasRecordedClassification
|| classification
== TOUCH_GESTURE_CLASSIFIED__CLASSIFICATION__UNKNOWN_CLASSIFICATION) {
// Only record the first classification for an event stream.
return;
}
if (mCurrentDownEvent == null || mCurrentMotionEvent == null) {
// If the complete event stream wasn't seen, don't record anything.
mHasRecordedClassification = true;
return;
}
FrameworkStatsLog.write(
FrameworkStatsLog.TOUCH_GESTURE_CLASSIFIED,
getClass().getName(),
classification,
(int) (SystemClock.uptimeMillis() - mCurrentMotionEvent.getDownTime()),
(float) Math.hypot(mCurrentMotionEvent.getRawX() - mCurrentDownEvent.getRawX(),
mCurrentMotionEvent.getRawY() - mCurrentDownEvent.getRawY()));
mHasRecordedClassification = true;
}
}