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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.graphics.drawable;
import com.android.internal.R;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import android.annotation.AttrRes;
import android.annotation.ColorInt;
import android.annotation.IntRange;
import android.annotation.NonNull;
import android.annotation.Nullable;
import android.annotation.TestApi;
import android.content.pm.ActivityInfo.Config;
import android.content.res.ColorStateList;
import android.content.res.Resources;
import android.content.res.Resources.Theme;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.ColorFilter;
import android.graphics.Insets;
import android.graphics.NinePatch;
import android.graphics.Outline;
import android.graphics.PixelFormat;
import android.graphics.PorterDuff;
import android.graphics.PorterDuff.Mode;
import android.graphics.PorterDuffColorFilter;
import android.graphics.Rect;
import android.graphics.Region;
import android.graphics.Xfermode;
import android.os.Trace;
import android.util.AttributeSet;
import android.util.DisplayMetrics;
import android.util.StateSet;
import android.util.TypedValue;
import android.util.Xml;
import android.view.View;
import java.io.IOException;
import java.io.InputStream;
import java.lang.ref.WeakReference;
import java.util.Arrays;
/**
* A Drawable is a general abstraction for "something that can be drawn." Most
* often you will deal with Drawable as the type of resource retrieved for
* drawing things to the screen; the Drawable class provides a generic API for
* dealing with an underlying visual resource that may take a variety of forms.
* Unlike a {@link android.view.View}, a Drawable does not have any facility to
* receive events or otherwise interact with the user.
*
* In addition to simple drawing, Drawable provides a number of generic
* mechanisms for its client to interact with what is being drawn:
*
*
* - The {@link #setBounds} method must be called to tell the
* Drawable where it is drawn and how large it should be. All Drawables
* should respect the requested size, often simply by scaling their
* imagery. A client can find the preferred size for some Drawables with
* the {@link #getIntrinsicHeight} and {@link #getIntrinsicWidth} methods.
*
*
- The {@link #getPadding} method can return from some Drawables
* information about how to frame content that is placed inside of them.
* For example, a Drawable that is intended to be the frame for a button
* widget would need to return padding that correctly places the label
* inside of itself.
*
*
- The {@link #setState} method allows the client to tell the Drawable
* in which state it is to be drawn, such as "focused", "selected", etc.
* Some drawables may modify their imagery based on the selected state.
*
*
- The {@link #setLevel} method allows the client to supply a single
* continuous controller that can modify the Drawable is displayed, such as
* a battery level or progress level. Some drawables may modify their
* imagery based on the current level.
*
*
- A Drawable can perform animations by calling back to its client
* through the {@link Callback} interface. All clients should support this
* interface (via {@link #setCallback}) so that animations will work. A
* simple way to do this is through the system facilities such as
* {@link android.view.View#setBackground(Drawable)} and
* {@link android.widget.ImageView}.
*
*
* Though usually not visible to the application, Drawables may take a variety
* of forms:
*
*
* - Bitmap: the simplest Drawable, a PNG or JPEG image.
*
- Nine Patch: an extension to the PNG format allows it to
* specify information about how to stretch it and place things inside of
* it.
*
- Vector: a drawable defined in an XML file as a set of points,
* lines, and curves along with its associated color information. This type
* of drawable can be scaled without loss of display quality.
*
- Shape: contains simple drawing commands instead of a raw
* bitmap, allowing it to resize better in some cases.
*
- Layers: a compound drawable, which draws multiple underlying
* drawables on top of each other.
*
- States: a compound drawable that selects one of a set of
* drawables based on its state.
*
- Levels: a compound drawable that selects one of a set of
* drawables based on its level.
*
- Scale: a compound drawable with a single child drawable,
* whose overall size is modified based on the current level.
*
*
*
* Custom drawables
*
*
* All versions of Android allow the Drawable class to be extended and used at
* run time in place of framework-provided drawable classes. Starting in
* {@link android.os.Build.VERSION_CODES#N API 24}, custom drawables classes
* may also be used in XML.
*
* Note: Custom drawable classes are only accessible from
* within your application package. Other applications will not be able to load
* them.
*
* At a minimum, custom drawable classes must implement the abstract methods on
* Drawable and should override the {@link Drawable#draw(Canvas)} method to
* draw content.
*
* Custom drawables classes may be used in XML in multiple ways:
*
* -
* Using the fully-qualified class name as the XML element name. For
* this method, the custom drawable class must be a public top-level
* class.
*
* <com.myapp.MyCustomDrawable xmlns:android="http://schemas.android.com/apk/res/android"
* android:color="#ffff0000" />
*
*
* -
* Using drawable as the XML element name and specifying the
* fully-qualified class name from the class attribute. This
* method may be used for both public top-level classes and public
* static inner classes.
*
* <drawable xmlns:android="http://schemas.android.com/apk/res/android"
* class="com.myapp.MyTopLevelClass$InnerCustomDrawable"
* android:color="#ffff0000" />
*
*
*
*
*
* Developer Guides
* For more information about how to use drawables, read the
* Canvas and Drawables developer
* guide. For information and examples of creating drawable resources (XML or bitmap files that
* can be loaded in code), read the
* Drawable Resources
* document.
*/
public abstract class Drawable {
private static final Rect ZERO_BOUNDS_RECT = new Rect();
static final PorterDuff.Mode DEFAULT_TINT_MODE = PorterDuff.Mode.SRC_IN;
private int[] mStateSet = StateSet.WILD_CARD;
private int mLevel = 0;
private @Config int mChangingConfigurations = 0;
private Rect mBounds = ZERO_BOUNDS_RECT; // lazily becomes a new Rect()
private WeakReference mCallback = null;
private boolean mVisible = true;
private int mLayoutDirection;
/**
* The source density to use when looking up resources using
* {@link Resources#getDrawableForDensity(int, int, Theme)}. A value of 0 means there is no
* override and the system density will be used.
*
* NOTE(adamlesinski): This is transient state used to get around the public API that does not
* account for source density overrides. Custom drawables implemented by developers do not need
* to be aware of the source density override, as it is only used by Launcher to load higher
* resolution icons from external Resources packages, which do not execute custom code.
* This is all to support the {@link Resources#getDrawableForDensity(int, int, Theme)} API.
*
* @hide
*/
protected int mSrcDensityOverride = 0;
/**
* Draw in its bounds (set via setBounds) respecting optional effects such
* as alpha (set via setAlpha) and color filter (set via setColorFilter).
*
* @param canvas The canvas to draw into
*/
public abstract void draw(@NonNull Canvas canvas);
/**
* Specify a bounding rectangle for the Drawable. This is where the drawable
* will draw when its draw() method is called.
*/
public void setBounds(int left, int top, int right, int bottom) {
Rect oldBounds = mBounds;
if (oldBounds == ZERO_BOUNDS_RECT) {
oldBounds = mBounds = new Rect();
}
if (oldBounds.left != left || oldBounds.top != top ||
oldBounds.right != right || oldBounds.bottom != bottom) {
if (!oldBounds.isEmpty()) {
// first invalidate the previous bounds
invalidateSelf();
}
mBounds.set(left, top, right, bottom);
onBoundsChange(mBounds);
}
}
/**
* Specify a bounding rectangle for the Drawable. This is where the drawable
* will draw when its draw() method is called.
*/
public void setBounds(@NonNull Rect bounds) {
setBounds(bounds.left, bounds.top, bounds.right, bounds.bottom);
}
/**
* Return a copy of the drawable's bounds in the specified Rect (allocated
* by the caller). The bounds specify where this will draw when its draw()
* method is called.
*
* @param bounds Rect to receive the drawable's bounds (allocated by the
* caller).
*/
public final void copyBounds(@NonNull Rect bounds) {
bounds.set(mBounds);
}
/**
* Return a copy of the drawable's bounds in a new Rect. This returns the
* same values as getBounds(), but the returned object is guaranteed to not
* be changed later by the drawable (i.e. it retains no reference to this
* rect). If the caller already has a Rect allocated, call copyBounds(rect).
*
* @return A copy of the drawable's bounds
*/
@NonNull
public final Rect copyBounds() {
return new Rect(mBounds);
}
/**
* Return the drawable's bounds Rect. Note: for efficiency, the returned
* object may be the same object stored in the drawable (though this is not
* guaranteed), so if a persistent copy of the bounds is needed, call
* copyBounds(rect) instead.
* You should also not change the object returned by this method as it may
* be the same object stored in the drawable.
*
* @return The bounds of the drawable (which may change later, so caller
* beware). DO NOT ALTER the returned object as it may change the
* stored bounds of this drawable.
*
* @see #copyBounds()
* @see #copyBounds(android.graphics.Rect)
*/
@NonNull
public final Rect getBounds() {
if (mBounds == ZERO_BOUNDS_RECT) {
mBounds = new Rect();
}
return mBounds;
}
/**
* Return the drawable's dirty bounds Rect. Note: for efficiency, the
* returned object may be the same object stored in the drawable (though
* this is not guaranteed).
*
* By default, this returns the full drawable bounds. Custom drawables may
* override this method to perform more precise invalidation.
*
* @return The dirty bounds of this drawable
*/
@NonNull
public Rect getDirtyBounds() {
return getBounds();
}
/**
* Set a mask of the configuration parameters for which this drawable
* may change, requiring that it be re-created.
*
* @param configs A mask of the changing configuration parameters, as
* defined by {@link android.content.pm.ActivityInfo}.
*
* @see android.content.pm.ActivityInfo
*/
public void setChangingConfigurations(@Config int configs) {
mChangingConfigurations = configs;
}
/**
* Return a mask of the configuration parameters for which this drawable
* may change, requiring that it be re-created. The default implementation
* returns whatever was provided through
* {@link #setChangingConfigurations(int)} or 0 by default. Subclasses
* may extend this to or in the changing configurations of any other
* drawables they hold.
*
* @return Returns a mask of the changing configuration parameters, as
* defined by {@link android.content.pm.ActivityInfo}.
*
* @see android.content.pm.ActivityInfo
*/
public @Config int getChangingConfigurations() {
return mChangingConfigurations;
}
/**
* Set to true to have the drawable dither its colors when drawn to a
* device with fewer than 8-bits per color component.
*
* @see android.graphics.Paint#setDither(boolean);
* @deprecated This property is ignored.
*/
@Deprecated
public void setDither(boolean dither) {}
/**
* Set to true to have the drawable filter its bitmaps with bilinear
* sampling when they are scaled or rotated.
*
*
This can improve appearance when bitmaps are rotated. If the drawable
* does not use bitmaps, this call is ignored.
*
* @see #isFilterBitmap()
* @see android.graphics.Paint#setFilterBitmap(boolean);
*/
public void setFilterBitmap(boolean filter) {}
/**
* @return whether this drawable filters its bitmaps
* @see #setFilterBitmap(boolean)
*/
public boolean isFilterBitmap() {
return false;
}
/**
* Implement this interface if you want to create an animated drawable that
* extends {@link android.graphics.drawable.Drawable Drawable}.
* Upon retrieving a drawable, use
* {@link Drawable#setCallback(android.graphics.drawable.Drawable.Callback)}
* to supply your implementation of the interface to the drawable; it uses
* this interface to schedule and execute animation changes.
*/
public interface Callback {
/**
* Called when the drawable needs to be redrawn. A view at this point
* should invalidate itself (or at least the part of itself where the
* drawable appears).
*
* @param who The drawable that is requesting the update.
*/
void invalidateDrawable(@NonNull Drawable who);
/**
* A Drawable can call this to schedule the next frame of its
* animation. An implementation can generally simply call
* {@link android.os.Handler#postAtTime(Runnable, Object, long)} with
* the parameters (what, who, when) to perform the
* scheduling.
*
* @param who The drawable being scheduled.
* @param what The action to execute.
* @param when The time (in milliseconds) to run. The timebase is
* {@link android.os.SystemClock#uptimeMillis}
*/
void scheduleDrawable(@NonNull Drawable who, @NonNull Runnable what, long when);
/**
* A Drawable can call this to unschedule an action previously
* scheduled with {@link #scheduleDrawable}. An implementation can
* generally simply call
* {@link android.os.Handler#removeCallbacks(Runnable, Object)} with
* the parameters (what, who) to unschedule the drawable.
*
* @param who The drawable being unscheduled.
* @param what The action being unscheduled.
*/
void unscheduleDrawable(@NonNull Drawable who, @NonNull Runnable what);
}
/**
* Bind a {@link Callback} object to this Drawable. Required for clients
* that want to support animated drawables.
*
* @param cb The client's Callback implementation.
*
* @see #getCallback()
*/
public final void setCallback(@Nullable Callback cb) {
mCallback = cb != null ? new WeakReference<>(cb) : null;
}
/**
* Return the current {@link Callback} implementation attached to this
* Drawable.
*
* @return A {@link Callback} instance or null if no callback was set.
*
* @see #setCallback(android.graphics.drawable.Drawable.Callback)
*/
@Nullable
public Callback getCallback() {
return mCallback != null ? mCallback.get() : null;
}
/**
* Use the current {@link Callback} implementation to have this Drawable
* redrawn. Does nothing if there is no Callback attached to the
* Drawable.
*
* @see Callback#invalidateDrawable
* @see #getCallback()
* @see #setCallback(android.graphics.drawable.Drawable.Callback)
*/
public void invalidateSelf() {
final Callback callback = getCallback();
if (callback != null) {
callback.invalidateDrawable(this);
}
}
/**
* Use the current {@link Callback} implementation to have this Drawable
* scheduled. Does nothing if there is no Callback attached to the
* Drawable.
*
* @param what The action being scheduled.
* @param when The time (in milliseconds) to run.
*
* @see Callback#scheduleDrawable
*/
public void scheduleSelf(@NonNull Runnable what, long when) {
final Callback callback = getCallback();
if (callback != null) {
callback.scheduleDrawable(this, what, when);
}
}
/**
* Use the current {@link Callback} implementation to have this Drawable
* unscheduled. Does nothing if there is no Callback attached to the
* Drawable.
*
* @param what The runnable that you no longer want called.
*
* @see Callback#unscheduleDrawable
*/
public void unscheduleSelf(@NonNull Runnable what) {
final Callback callback = getCallback();
if (callback != null) {
callback.unscheduleDrawable(this, what);
}
}
/**
* Returns the resolved layout direction for this Drawable.
*
* @return One of {@link android.view.View#LAYOUT_DIRECTION_LTR},
* {@link android.view.View#LAYOUT_DIRECTION_RTL}
* @see #setLayoutDirection(int)
*/
public @View.ResolvedLayoutDir int getLayoutDirection() {
return mLayoutDirection;
}
/**
* Set the layout direction for this drawable. Should be a resolved
* layout direction, as the Drawable has no capacity to do the resolution on
* its own.
*
* @param layoutDirection the resolved layout direction for the drawable,
* either {@link android.view.View#LAYOUT_DIRECTION_LTR}
* or {@link android.view.View#LAYOUT_DIRECTION_RTL}
* @return {@code true} if the layout direction change has caused the
* appearance of the drawable to change such that it needs to be
* re-drawn, {@code false} otherwise
* @see #getLayoutDirection()
*/
public final boolean setLayoutDirection(@View.ResolvedLayoutDir int layoutDirection) {
if (mLayoutDirection != layoutDirection) {
mLayoutDirection = layoutDirection;
return onLayoutDirectionChanged(layoutDirection);
}
return false;
}
/**
* Called when the drawable's resolved layout direction changes.
*
* @param layoutDirection the new resolved layout direction
* @return {@code true} if the layout direction change has caused the
* appearance of the drawable to change such that it needs to be
* re-drawn, {@code false} otherwise
* @see #setLayoutDirection(int)
*/
public boolean onLayoutDirectionChanged(@View.ResolvedLayoutDir int layoutDirection) {
return false;
}
/**
* Specify an alpha value for the drawable. 0 means fully transparent, and
* 255 means fully opaque.
*/
public abstract void setAlpha(@IntRange(from=0,to=255) int alpha);
/**
* Gets the current alpha value for the drawable. 0 means fully transparent,
* 255 means fully opaque. This method is implemented by
* Drawable subclasses and the value returned is specific to how that class treats alpha.
* The default return value is 255 if the class does not override this method to return a value
* specific to its use of alpha.
*/
@IntRange(from=0,to=255)
public int getAlpha() {
return 0xFF;
}
/**
* @hide
*
* Internal-only method for setting xfermode on certain supported drawables.
*
* Should not be made public since the layers and drawing area with which
* Drawables draw is private implementation detail, and not something apps
* should rely upon.
*/
public void setXfermode(@Nullable Xfermode mode) {
// Base implementation drops it on the floor for compatibility. Whee!
}
/**
* Specify an optional color filter for the drawable.
*
* If a Drawable has a ColorFilter, each output pixel of the Drawable's
* drawing contents will be modified by the color filter before it is
* blended onto the render target of a Canvas.
*
*
* Pass {@code null} to remove any existing color filter.
*
* Note: Setting a non-{@code null} color
* filter disables {@link #setTintList(ColorStateList) tint}.
*
*
* @param colorFilter The color filter to apply, or {@code null} to remove the
* existing color filter
*/
public abstract void setColorFilter(@Nullable ColorFilter colorFilter);
/**
* Specify a color and Porter-Duff mode to be the color filter for this
* drawable.
*
* Convenience for {@link #setColorFilter(ColorFilter)} which constructs a
* {@link PorterDuffColorFilter}.
*
* Note: Setting a color filter disables
* {@link #setTintList(ColorStateList) tint}.
*
*/
public void setColorFilter(@ColorInt int color, @NonNull PorterDuff.Mode mode) {
if (getColorFilter() instanceof PorterDuffColorFilter) {
PorterDuffColorFilter existing = (PorterDuffColorFilter) getColorFilter();
if (existing.getColor() == color && existing.getMode() == mode) {
return;
}
}
setColorFilter(new PorterDuffColorFilter(color, mode));
}
/**
* Specifies tint color for this drawable.
*
* A Drawable's drawing content will be blended together with its tint
* before it is drawn to the screen. This functions similarly to
* {@link #setColorFilter(int, PorterDuff.Mode)}.
*
*
* To clear the tint, pass {@code null} to
* {@link #setTintList(ColorStateList)}.
*
* Note: Setting a color filter via
* {@link #setColorFilter(ColorFilter)} or
* {@link #setColorFilter(int, PorterDuff.Mode)} overrides tint.
*
*
* @param tintColor Color to use for tinting this drawable
* @see #setTintList(ColorStateList)
* @see #setTintMode(PorterDuff.Mode)
*/
public void setTint(@ColorInt int tintColor) {
setTintList(ColorStateList.valueOf(tintColor));
}
/**
* Specifies tint color for this drawable as a color state list.
*
* A Drawable's drawing content will be blended together with its tint
* before it is drawn to the screen. This functions similarly to
* {@link #setColorFilter(int, PorterDuff.Mode)}.
*
* Note: Setting a color filter via
* {@link #setColorFilter(ColorFilter)} or
* {@link #setColorFilter(int, PorterDuff.Mode)} overrides tint.
*
*
* @param tint Color state list to use for tinting this drawable, or
* {@code null} to clear the tint
* @see #setTint(int)
* @see #setTintMode(PorterDuff.Mode)
*/
public void setTintList(@Nullable ColorStateList tint) {}
/**
* Specifies a tint blending mode for this drawable.
*
* Defines how this drawable's tint color should be blended into the drawable
* before it is drawn to screen. Default tint mode is {@link PorterDuff.Mode#SRC_IN}.
*
* Note: Setting a color filter via
* {@link #setColorFilter(ColorFilter)} or
* {@link #setColorFilter(int, PorterDuff.Mode)} overrides tint.
*
*
* @param tintMode A Porter-Duff blending mode
* @see #setTint(int)
* @see #setTintList(ColorStateList)
*/
public void setTintMode(@NonNull PorterDuff.Mode tintMode) {}
/**
* Returns the current color filter, or {@code null} if none set.
*
* @return the current color filter, or {@code null} if none set
*/
public @Nullable ColorFilter getColorFilter() {
return null;
}
/**
* Removes the color filter for this drawable.
*/
public void clearColorFilter() {
setColorFilter(null);
}
/**
* Specifies the hotspot's location within the drawable.
*
* @param x The X coordinate of the center of the hotspot
* @param y The Y coordinate of the center of the hotspot
*/
public void setHotspot(float x, float y) {}
/**
* Sets the bounds to which the hotspot is constrained, if they should be
* different from the drawable bounds.
*
* @param left position in pixels of the left bound
* @param top position in pixels of the top bound
* @param right position in pixels of the right bound
* @param bottom position in pixels of the bottom bound
* @see #getHotspotBounds(android.graphics.Rect)
*/
public void setHotspotBounds(int left, int top, int right, int bottom) {}
/**
* Populates {@code outRect} with the hotspot bounds.
*
* @param outRect the rect to populate with the hotspot bounds
* @see #setHotspotBounds(int, int, int, int)
*/
public void getHotspotBounds(@NonNull Rect outRect) {
outRect.set(getBounds());
}
/**
* Whether this drawable requests projection.
*
* @hide magic!
*/
public boolean isProjected() {
return false;
}
/**
* Indicates whether this drawable will change its appearance based on
* state. Clients can use this to determine whether it is necessary to
* calculate their state and call setState.
*
* @return True if this drawable changes its appearance based on state,
* false otherwise.
* @see #setState(int[])
*/
public boolean isStateful() {
return false;
}
/**
* Indicates whether this drawable has at least one state spec explicitly
* specifying {@link android.R.attr#state_focused}.
*
* Note: A View uses a {@link Drawable} instance as its background and it
* changes its appearance based on a state. On keyboard devices, it should
* specify its {@link android.R.attr#state_focused} to make sure the user
* knows which view is holding the focus.
*
* @return {@code true} if {@link android.R.attr#state_focused} is specified
* for this drawable.
*
* @hide
*/
@TestApi
public boolean hasFocusStateSpecified() {
return false;
}
/**
* Specify a set of states for the drawable. These are use-case specific,
* so see the relevant documentation. As an example, the background for
* widgets like Button understand the following states:
* [{@link android.R.attr#state_focused},
* {@link android.R.attr#state_pressed}].
*
* If the new state you are supplying causes the appearance of the
* Drawable to change, then it is responsible for calling
* {@link #invalidateSelf} in order to have itself redrawn, and
* true will be returned from this function.
*
*
Note: The Drawable holds a reference on to stateSet
* until a new state array is given to it, so you must not modify this
* array during that time.
*
* @param stateSet The new set of states to be displayed.
*
* @return Returns true if this change in state has caused the appearance
* of the Drawable to change (hence requiring an invalidate), otherwise
* returns false.
*/
public boolean setState(@NonNull final int[] stateSet) {
if (!Arrays.equals(mStateSet, stateSet)) {
mStateSet = stateSet;
return onStateChange(stateSet);
}
return false;
}
/**
* Describes the current state, as a union of primitve states, such as
* {@link android.R.attr#state_focused},
* {@link android.R.attr#state_selected}, etc.
* Some drawables may modify their imagery based on the selected state.
* @return An array of resource Ids describing the current state.
*/
public @NonNull int[] getState() {
return mStateSet;
}
/**
* If this Drawable does transition animations between states, ask that
* it immediately jump to the current state and skip any active animations.
*/
public void jumpToCurrentState() {
}
/**
* @return The current drawable that will be used by this drawable. For simple drawables, this
* is just the drawable itself. For drawables that change state like
* {@link StateListDrawable} and {@link LevelListDrawable} this will be the child drawable
* currently in use.
*/
public @NonNull Drawable getCurrent() {
return this;
}
/**
* Specify the level for the drawable. This allows a drawable to vary its
* imagery based on a continuous controller, for example to show progress
* or volume level.
*
* If the new level you are supplying causes the appearance of the
* Drawable to change, then it is responsible for calling
* {@link #invalidateSelf} in order to have itself redrawn, and
* true will be returned from this function.
*
* @param level The new level, from 0 (minimum) to 10000 (maximum).
*
* @return Returns true if this change in level has caused the appearance
* of the Drawable to change (hence requiring an invalidate), otherwise
* returns false.
*/
public final boolean setLevel(@IntRange(from=0,to=10000) int level) {
if (mLevel != level) {
mLevel = level;
return onLevelChange(level);
}
return false;
}
/**
* Retrieve the current level.
*
* @return int Current level, from 0 (minimum) to 10000 (maximum).
*/
public final @IntRange(from=0,to=10000) int getLevel() {
return mLevel;
}
/**
* Set whether this Drawable is visible. This generally does not impact
* the Drawable's behavior, but is a hint that can be used by some
* Drawables, for example, to decide whether run animations.
*
* @param visible Set to true if visible, false if not.
* @param restart You can supply true here to force the drawable to behave
* as if it has just become visible, even if it had last
* been set visible. Used for example to force animations
* to restart.
*
* @return boolean Returns true if the new visibility is different than
* its previous state.
*/
public boolean setVisible(boolean visible, boolean restart) {
boolean changed = mVisible != visible;
if (changed) {
mVisible = visible;
invalidateSelf();
}
return changed;
}
public final boolean isVisible() {
return mVisible;
}
/**
* Set whether this Drawable is automatically mirrored when its layout direction is RTL
* (right-to left). See {@link android.util.LayoutDirection}.
*
* @param mirrored Set to true if the Drawable should be mirrored, false if not.
*/
public void setAutoMirrored(boolean mirrored) {
}
/**
* Tells if this Drawable will be automatically mirrored when its layout direction is RTL
* right-to-left. See {@link android.util.LayoutDirection}.
*
* @return boolean Returns true if this Drawable will be automatically mirrored.
*/
public boolean isAutoMirrored() {
return false;
}
/**
* Applies the specified theme to this Drawable and its children.
*
* @param t the theme to apply
*/
public void applyTheme(@NonNull @SuppressWarnings("unused") Theme t) {
}
public boolean canApplyTheme() {
return false;
}
/**
* Return the opacity/transparency of this Drawable. The returned value is
* one of the abstract format constants in
* {@link android.graphics.PixelFormat}:
* {@link android.graphics.PixelFormat#UNKNOWN},
* {@link android.graphics.PixelFormat#TRANSLUCENT},
* {@link android.graphics.PixelFormat#TRANSPARENT}, or
* {@link android.graphics.PixelFormat#OPAQUE}.
*
*
An OPAQUE drawable is one that draws all all content within its bounds, completely
* covering anything behind the drawable. A TRANSPARENT drawable is one that draws nothing
* within its bounds, allowing everything behind it to show through. A TRANSLUCENT drawable
* is a drawable in any other state, where the drawable will draw some, but not all,
* of the content within its bounds and at least some content behind the drawable will
* be visible. If the visibility of the drawable's contents cannot be determined, the
* safest/best return value is TRANSLUCENT.
*
*
Generally a Drawable should be as conservative as possible with the
* value it returns. For example, if it contains multiple child drawables
* and only shows one of them at a time, if only one of the children is
* TRANSLUCENT and the others are OPAQUE then TRANSLUCENT should be
* returned. You can use the method {@link #resolveOpacity} to perform a
* standard reduction of two opacities to the appropriate single output.
*
*
Note that the returned value does not necessarily take into account a
* custom alpha or color filter that has been applied by the client through
* the {@link #setAlpha} or {@link #setColorFilter} methods. Some subclasses,
* such as {@link BitmapDrawable}, {@link ColorDrawable}, and {@link GradientDrawable},
* do account for the value of {@link #setAlpha}, but the general behavior is dependent
* upon the implementation of the subclass.
*
* @return int The opacity class of the Drawable.
*
* @see android.graphics.PixelFormat
*/
public abstract @PixelFormat.Opacity int getOpacity();
/**
* Return the appropriate opacity value for two source opacities. If
* either is UNKNOWN, that is returned; else, if either is TRANSLUCENT,
* that is returned; else, if either is TRANSPARENT, that is returned;
* else, OPAQUE is returned.
*
*
This is to help in implementing {@link #getOpacity}.
*
* @param op1 One opacity value.
* @param op2 Another opacity value.
*
* @return int The combined opacity value.
*
* @see #getOpacity
*/
public static @PixelFormat.Opacity int resolveOpacity(@PixelFormat.Opacity int op1,
@PixelFormat.Opacity int op2) {
if (op1 == op2) {
return op1;
}
if (op1 == PixelFormat.UNKNOWN || op2 == PixelFormat.UNKNOWN) {
return PixelFormat.UNKNOWN;
}
if (op1 == PixelFormat.TRANSLUCENT || op2 == PixelFormat.TRANSLUCENT) {
return PixelFormat.TRANSLUCENT;
}
if (op1 == PixelFormat.TRANSPARENT || op2 == PixelFormat.TRANSPARENT) {
return PixelFormat.TRANSPARENT;
}
return PixelFormat.OPAQUE;
}
/**
* Returns a Region representing the part of the Drawable that is completely
* transparent. This can be used to perform drawing operations, identifying
* which parts of the target will not change when rendering the Drawable.
* The default implementation returns null, indicating no transparent
* region; subclasses can optionally override this to return an actual
* Region if they want to supply this optimization information, but it is
* not required that they do so.
*
* @return Returns null if the Drawables has no transparent region to
* report, else a Region holding the parts of the Drawable's bounds that
* are transparent.
*/
public @Nullable Region getTransparentRegion() {
return null;
}
/**
* Override this in your subclass to change appearance if you recognize the
* specified state.
*
* @return Returns true if the state change has caused the appearance of
* the Drawable to change (that is, it needs to be drawn), else false
* if it looks the same and there is no need to redraw it since its
* last state.
*/
protected boolean onStateChange(int[] state) {
return false;
}
/** Override this in your subclass to change appearance if you vary based
* on level.
* @return Returns true if the level change has caused the appearance of
* the Drawable to change (that is, it needs to be drawn), else false
* if it looks the same and there is no need to redraw it since its
* last level.
*/
protected boolean onLevelChange(int level) {
return false;
}
/**
* Override this in your subclass to change appearance if you vary based on
* the bounds.
*/
protected void onBoundsChange(Rect bounds) {
// Stub method.
}
/**
* Returns the drawable's intrinsic width.
*
* Intrinsic width is the width at which the drawable would like to be laid
* out, including any inherent padding. If the drawable has no intrinsic
* width, such as a solid color, this method returns -1.
*
* @return the intrinsic width, or -1 if no intrinsic width
*/
public int getIntrinsicWidth() {
return -1;
}
/**
* Returns the drawable's intrinsic height.
*
* Intrinsic height is the height at which the drawable would like to be
* laid out, including any inherent padding. If the drawable has no
* intrinsic height, such as a solid color, this method returns -1.
*
* @return the intrinsic height, or -1 if no intrinsic height
*/
public int getIntrinsicHeight() {
return -1;
}
/**
* Returns the minimum width suggested by this Drawable. If a View uses this
* Drawable as a background, it is suggested that the View use at least this
* value for its width. (There will be some scenarios where this will not be
* possible.) This value should INCLUDE any padding.
*
* @return The minimum width suggested by this Drawable. If this Drawable
* doesn't have a suggested minimum width, 0 is returned.
*/
public int getMinimumWidth() {
final int intrinsicWidth = getIntrinsicWidth();
return intrinsicWidth > 0 ? intrinsicWidth : 0;
}
/**
* Returns the minimum height suggested by this Drawable. If a View uses this
* Drawable as a background, it is suggested that the View use at least this
* value for its height. (There will be some scenarios where this will not be
* possible.) This value should INCLUDE any padding.
*
* @return The minimum height suggested by this Drawable. If this Drawable
* doesn't have a suggested minimum height, 0 is returned.
*/
public int getMinimumHeight() {
final int intrinsicHeight = getIntrinsicHeight();
return intrinsicHeight > 0 ? intrinsicHeight : 0;
}
/**
* Return in padding the insets suggested by this Drawable for placing
* content inside the drawable's bounds. Positive values move toward the
* center of the Drawable (set Rect.inset).
*
* @return true if this drawable actually has a padding, else false. When false is returned,
* the padding is always set to 0.
*/
public boolean getPadding(@NonNull Rect padding) {
padding.set(0, 0, 0, 0);
return false;
}
/**
* Return in insets the layout insets suggested by this Drawable for use with alignment
* operations during layout.
*
* @hide
*/
public @NonNull Insets getOpticalInsets() {
return Insets.NONE;
}
/**
* Called to get the drawable to populate the Outline that defines its drawing area.
*
* This method is called by the default {@link android.view.ViewOutlineProvider} to define
* the outline of the View.
*
* The default behavior defines the outline to be the bounding rectangle of 0 alpha.
* Subclasses that wish to convey a different shape or alpha value must override this method.
*
* @see android.view.View#setOutlineProvider(android.view.ViewOutlineProvider)
*/
public void getOutline(@NonNull Outline outline) {
outline.setRect(getBounds());
outline.setAlpha(0);
}
/**
* Make this drawable mutable. This operation cannot be reversed. A mutable
* drawable is guaranteed to not share its state with any other drawable.
* This is especially useful when you need to modify properties of drawables
* loaded from resources. By default, all drawables instances loaded from
* the same resource share a common state; if you modify the state of one
* instance, all the other instances will receive the same modification.
*
* Calling this method on a mutable Drawable will have no effect.
*
* @return This drawable.
* @see ConstantState
* @see #getConstantState()
*/
public @NonNull Drawable mutate() {
return this;
}
/**
* Clears the mutated state, allowing this drawable to be cached and
* mutated again.
*
* This is hidden because only framework drawables can be cached, so
* custom drawables don't need to support constant state, mutate(), or
* clearMutated().
*
* @hide
*/
public void clearMutated() {
// Default implementation is no-op.
}
/**
* Create a drawable from an inputstream
*/
public static Drawable createFromStream(InputStream is, String srcName) {
Trace.traceBegin(Trace.TRACE_TAG_RESOURCES, srcName != null ? srcName : "Unknown drawable");
try {
return createFromResourceStream(null, null, is, srcName);
} finally {
Trace.traceEnd(Trace.TRACE_TAG_RESOURCES);
}
}
/**
* Create a drawable from an inputstream, using the given resources and
* value to determine density information.
*/
public static Drawable createFromResourceStream(Resources res, TypedValue value,
InputStream is, String srcName) {
Trace.traceBegin(Trace.TRACE_TAG_RESOURCES, srcName != null ? srcName : "Unknown drawable");
try {
return createFromResourceStream(res, value, is, srcName, null);
} finally {
Trace.traceEnd(Trace.TRACE_TAG_RESOURCES);
}
}
/**
* Create a drawable from an inputstream, using the given resources and
* value to determine density information.
*/
public static Drawable createFromResourceStream(Resources res, TypedValue value,
InputStream is, String srcName, BitmapFactory.Options opts) {
if (is == null) {
return null;
}
/* ugh. The decodeStream contract is that we have already allocated
the pad rect, but if the bitmap does not had a ninepatch chunk,
then the pad will be ignored. If we could change this to lazily
alloc/assign the rect, we could avoid the GC churn of making new
Rects only to drop them on the floor.
*/
Rect pad = new Rect();
// Special stuff for compatibility mode: if the target density is not
// the same as the display density, but the resource -is- the same as
// the display density, then don't scale it down to the target density.
// This allows us to load the system's density-correct resources into
// an application in compatibility mode, without scaling those down
// to the compatibility density only to have them scaled back up when
// drawn to the screen.
if (opts == null) opts = new BitmapFactory.Options();
opts.inScreenDensity = Drawable.resolveDensity(res, 0);
Bitmap bm = BitmapFactory.decodeResourceStream(res, value, is, pad, opts);
if (bm != null) {
byte[] np = bm.getNinePatchChunk();
if (np == null || !NinePatch.isNinePatchChunk(np)) {
np = null;
pad = null;
}
final Rect opticalInsets = new Rect();
bm.getOpticalInsets(opticalInsets);
return drawableFromBitmap(res, bm, np, pad, opticalInsets, srcName);
}
return null;
}
/**
* Create a drawable from an XML document. For more information on how to
* create resources in XML, see
* Drawable Resources.
*/
@NonNull
public static Drawable createFromXml(@NonNull Resources r, @NonNull XmlPullParser parser)
throws XmlPullParserException, IOException {
return createFromXml(r, parser, null);
}
/**
* Create a drawable from an XML document using an optional {@link Theme}.
* For more information on how to create resources in XML, see
* Drawable Resources.
*/
@NonNull
public static Drawable createFromXml(@NonNull Resources r, @NonNull XmlPullParser parser,
@Nullable Theme theme) throws XmlPullParserException, IOException {
return createFromXmlForDensity(r, parser, 0, theme);
}
/**
* Version of {@link #createFromXml(Resources, XmlPullParser, Theme)} that accepts a density
* override.
* @hide
*/
@NonNull
public static Drawable createFromXmlForDensity(@NonNull Resources r,
@NonNull XmlPullParser parser, int density, @Nullable Theme theme)
throws XmlPullParserException, IOException {
AttributeSet attrs = Xml.asAttributeSet(parser);
int type;
//noinspection StatementWithEmptyBody
while ((type=parser.next()) != XmlPullParser.START_TAG
&& type != XmlPullParser.END_DOCUMENT) {
// Empty loop.
}
if (type != XmlPullParser.START_TAG) {
throw new XmlPullParserException("No start tag found");
}
Drawable drawable = createFromXmlInnerForDensity(r, parser, attrs, density, theme);
if (drawable == null) {
throw new RuntimeException("Unknown initial tag: " + parser.getName());
}
return drawable;
}
/**
* Create from inside an XML document. Called on a parser positioned at
* a tag in an XML document, tries to create a Drawable from that tag.
* Returns null if the tag is not a valid drawable.
*/
@NonNull
public static Drawable createFromXmlInner(@NonNull Resources r, @NonNull XmlPullParser parser,
@NonNull AttributeSet attrs) throws XmlPullParserException, IOException {
return createFromXmlInner(r, parser, attrs, null);
}
/**
* Create a drawable from inside an XML document using an optional
* {@link Theme}. Called on a parser positioned at a tag in an XML
* document, tries to create a Drawable from that tag. Returns {@code null}
* if the tag is not a valid drawable.
*/
@NonNull
public static Drawable createFromXmlInner(@NonNull Resources r, @NonNull XmlPullParser parser,
@NonNull AttributeSet attrs, @Nullable Theme theme)
throws XmlPullParserException, IOException {
return createFromXmlInnerForDensity(r, parser, attrs, 0, theme);
}
/**
* Version of {@link #createFromXmlInner(Resources, XmlPullParser, AttributeSet, Theme)} that
* accepts an override density.
*/
@NonNull
static Drawable createFromXmlInnerForDensity(@NonNull Resources r,
@NonNull XmlPullParser parser, @NonNull AttributeSet attrs, int density,
@Nullable Theme theme) throws XmlPullParserException, IOException {
return r.getDrawableInflater().inflateFromXmlForDensity(parser.getName(), parser, attrs,
density, theme);
}
/**
* Create a drawable from file path name.
*/
@Nullable
public static Drawable createFromPath(String pathName) {
if (pathName == null) {
return null;
}
Trace.traceBegin(Trace.TRACE_TAG_RESOURCES, pathName);
try {
Bitmap bm = BitmapFactory.decodeFile(pathName);
if (bm != null) {
return drawableFromBitmap(null, bm, null, null, null, pathName);
}
} finally {
Trace.traceEnd(Trace.TRACE_TAG_RESOURCES);
}
return null;
}
/**
* Inflate this Drawable from an XML resource. Does not apply a theme.
*
* @see #inflate(Resources, XmlPullParser, AttributeSet, Theme)
*/
public void inflate(@NonNull Resources r, @NonNull XmlPullParser parser,
@NonNull AttributeSet attrs) throws XmlPullParserException, IOException {
inflate(r, parser, attrs, null);
}
/**
* Inflate this Drawable from an XML resource optionally styled by a theme.
* This can't be called more than once for each Drawable. Note that framework may have called
* this once to create the Drawable instance from XML resource.
*
* @param r Resources used to resolve attribute values
* @param parser XML parser from which to inflate this Drawable
* @param attrs Base set of attribute values
* @param theme Theme to apply, may be null
* @throws XmlPullParserException
* @throws IOException
*/
public void inflate(@NonNull Resources r, @NonNull XmlPullParser parser,
@NonNull AttributeSet attrs, @Nullable Theme theme)
throws XmlPullParserException, IOException {
final TypedArray a = obtainAttributes(r, theme, attrs, R.styleable.Drawable);
mVisible = a.getBoolean(R.styleable.Drawable_visible, mVisible);
a.recycle();
}
/**
* Inflate a Drawable from an XML resource.
*
* @throws XmlPullParserException
* @throws IOException
*/
void inflateWithAttributes(@NonNull @SuppressWarnings("unused") Resources r,
@NonNull @SuppressWarnings("unused") XmlPullParser parser, @NonNull TypedArray attrs,
@AttrRes int visibleAttr) throws XmlPullParserException, IOException {
mVisible = attrs.getBoolean(visibleAttr, mVisible);
}
/**
* Sets the source override density for this Drawable. If non-zero, this density is to be used
* for any calls to {@link Resources#getDrawableForDensity(int, int, Theme)} or
* {@link Resources#getValueForDensity(int, int, TypedValue, boolean)}.
* @hide
*/
final void setSrcDensityOverride(int density) {
mSrcDensityOverride = density;
}
/**
* This abstract class is used by {@link Drawable}s to store shared constant state and data
* between Drawables. {@link BitmapDrawable}s created from the same resource will for instance
* share a unique bitmap stored in their ConstantState.
*
*
* {@link #newDrawable(Resources)} can be used as a factory to create new Drawable instances
* from this ConstantState.
*
*
* Use {@link Drawable#getConstantState()} to retrieve the ConstantState of a Drawable. Calling
* {@link Drawable#mutate()} on a Drawable should typically create a new ConstantState for that
* Drawable.
*/
public static abstract class ConstantState {
/**
* Creates a new Drawable instance from its constant state.
*
* Note: Using this method means density-dependent
* properties, such as pixel dimensions or bitmap images, will not be
* updated to match the density of the target display. To ensure
* correct scaling, use {@link #newDrawable(Resources)} instead to
* provide an appropriate Resources object.
*
* @return a new drawable object based on this constant state
* @see #newDrawable(Resources)
*/
public abstract @NonNull Drawable newDrawable();
/**
* Creates a new Drawable instance from its constant state using the
* specified resources. This method should be implemented for drawables
* that have density-dependent properties.
*
* The default implementation for this method calls through to
* {@link #newDrawable()}.
*
* @param res the resources of the context in which the drawable will
* be displayed
* @return a new drawable object based on this constant state
*/
public @NonNull Drawable newDrawable(@Nullable Resources res) {
return newDrawable();
}
/**
* Creates a new Drawable instance from its constant state using the
* specified resources and theme. This method should be implemented for
* drawables that have theme-dependent properties.
*
* The default implementation for this method calls through to
* {@link #newDrawable(Resources)}.
*
* @param res the resources of the context in which the drawable will
* be displayed
* @param theme the theme of the context in which the drawable will be
* displayed
* @return a new drawable object based on this constant state
*/
public @NonNull Drawable newDrawable(@Nullable Resources res,
@Nullable @SuppressWarnings("unused") Theme theme) {
return newDrawable(res);
}
/**
* Return a bit mask of configuration changes that will impact
* this drawable (and thus require completely reloading it).
*/
public abstract @Config int getChangingConfigurations();
/**
* Return whether this constant state can have a theme applied.
*/
public boolean canApplyTheme() {
return false;
}
}
/**
* Return a {@link ConstantState} instance that holds the shared state of this Drawable.
*
* @return The ConstantState associated to that Drawable.
* @see ConstantState
* @see Drawable#mutate()
*/
public @Nullable ConstantState getConstantState() {
return null;
}
private static Drawable drawableFromBitmap(Resources res, Bitmap bm, byte[] np,
Rect pad, Rect layoutBounds, String srcName) {
if (np != null) {
return new NinePatchDrawable(res, bm, np, pad, layoutBounds, srcName);
}
return new BitmapDrawable(res, bm);
}
/**
* Ensures the tint filter is consistent with the current tint color and
* mode.
*/
@Nullable PorterDuffColorFilter updateTintFilter(@Nullable PorterDuffColorFilter tintFilter,
@Nullable ColorStateList tint, @Nullable PorterDuff.Mode tintMode) {
if (tint == null || tintMode == null) {
return null;
}
final int color = tint.getColorForState(getState(), Color.TRANSPARENT);
if (tintFilter == null) {
return new PorterDuffColorFilter(color, tintMode);
}
tintFilter.setColor(color);
tintFilter.setMode(tintMode);
return tintFilter;
}
/**
* Obtains styled attributes from the theme, if available, or unstyled
* resources if the theme is null.
* @hide
*/
protected static @NonNull TypedArray obtainAttributes(@NonNull Resources res,
@Nullable Theme theme, @NonNull AttributeSet set, @NonNull int[] attrs) {
if (theme == null) {
return res.obtainAttributes(set, attrs);
}
return theme.obtainStyledAttributes(set, attrs, 0, 0);
}
/**
* Scales a floating-point pixel value from the source density to the
* target density.
*
* @param pixels the pixel value for use in source density
* @param sourceDensity the source density
* @param targetDensity the target density
* @return the scaled pixel value for use in target density
*/
static float scaleFromDensity(float pixels, int sourceDensity, int targetDensity) {
return pixels * targetDensity / sourceDensity;
}
/**
* Scales a pixel value from the source density to the target density,
* optionally handling the resulting pixel value as a size rather than an
* offset.
*
* A size conversion involves rounding the base value and ensuring that
* a non-zero base value is at least one pixel in size.
*
* An offset conversion involves simply truncating the base value to an
* integer.
*
* @param pixels the pixel value for use in source density
* @param sourceDensity the source density
* @param targetDensity the target density
* @param isSize {@code true} to handle the resulting scaled value as a
* size, or {@code false} to handle it as an offset
* @return the scaled pixel value for use in target density
*/
static int scaleFromDensity(
int pixels, int sourceDensity, int targetDensity, boolean isSize) {
if (pixels == 0 || sourceDensity == targetDensity) {
return pixels;
}
final float result = pixels * targetDensity / (float) sourceDensity;
if (!isSize) {
return (int) result;
}
final int rounded = Math.round(result);
if (rounded != 0) {
return rounded;
} else if (pixels > 0) {
return 1;
} else {
return -1;
}
}
static int resolveDensity(@Nullable Resources r, int parentDensity) {
final int densityDpi = r == null ? parentDensity : r.getDisplayMetrics().densityDpi;
return densityDpi == 0 ? DisplayMetrics.DENSITY_DEFAULT : densityDpi;
}
/**
* Re-throws an exception as a {@link RuntimeException} with an empty stack
* trace to avoid cluttering the log. The original exception's stack trace
* will still be included.
*
* @param cause the exception to re-throw
* @throws RuntimeException
*/
static void rethrowAsRuntimeException(@NonNull Exception cause) throws RuntimeException {
final RuntimeException e = new RuntimeException(cause);
e.setStackTrace(new StackTraceElement[0]);
throw e;
}
/**
* Parses a {@link android.graphics.PorterDuff.Mode} from a tintMode
* attribute's enum value.
*
* @hide
*/
public static PorterDuff.Mode parseTintMode(int value, Mode defaultMode) {
switch (value) {
case 3: return Mode.SRC_OVER;
case 5: return Mode.SRC_IN;
case 9: return Mode.SRC_ATOP;
case 14: return Mode.MULTIPLY;
case 15: return Mode.SCREEN;
case 16: return Mode.ADD;
default: return defaultMode;
}
}
}