| /* |
| * Copyright (C) 2015 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.animation; |
| |
| import android.os.SystemClock; |
| import android.util.ArrayMap; |
| import android.view.Choreographer; |
| |
| import java.util.ArrayList; |
| |
| /** |
| * This custom, static handler handles the timing pulse that is shared by all active |
| * ValueAnimators. This approach ensures that the setting of animation values will happen on the |
| * same thread that animations start on, and that all animations will share the same times for |
| * calculating their values, which makes synchronizing animations possible. |
| * |
| * The handler uses the Choreographer by default for doing periodic callbacks. A custom |
| * AnimationFrameCallbackProvider can be set on the handler to provide timing pulse that |
| * may be independent of UI frame update. This could be useful in testing. |
| * |
| * @hide |
| */ |
| public class AnimationHandler { |
| /** |
| * Internal per-thread collections used to avoid set collisions as animations start and end |
| * while being processed. |
| * @hide |
| */ |
| private final ArrayMap<AnimationFrameCallback, Long> mDelayedCallbackStartTime = |
| new ArrayMap<>(); |
| private final ArrayList<AnimationFrameCallback> mAnimationCallbacks = |
| new ArrayList<>(); |
| private final ArrayList<AnimationFrameCallback> mCommitCallbacks = |
| new ArrayList<>(); |
| private AnimationFrameCallbackProvider mProvider; |
| |
| private final Choreographer.FrameCallback mFrameCallback = new Choreographer.FrameCallback() { |
| @Override |
| public void doFrame(long frameTimeNanos) { |
| doAnimationFrame(getProvider().getFrameTime()); |
| if (mAnimationCallbacks.size() > 0) { |
| getProvider().postFrameCallback(this); |
| } |
| } |
| }; |
| |
| public final static ThreadLocal<AnimationHandler> sAnimatorHandler = new ThreadLocal<>(); |
| private boolean mListDirty = false; |
| |
| public static AnimationHandler getInstance() { |
| if (sAnimatorHandler.get() == null) { |
| sAnimatorHandler.set(new AnimationHandler()); |
| } |
| return sAnimatorHandler.get(); |
| } |
| |
| /** |
| * By default, the Choreographer is used to provide timing for frame callbacks. A custom |
| * provider can be used here to provide different timing pulse. |
| */ |
| public void setProvider(AnimationFrameCallbackProvider provider) { |
| if (provider == null) { |
| mProvider = new MyFrameCallbackProvider(); |
| } else { |
| mProvider = provider; |
| } |
| } |
| |
| private AnimationFrameCallbackProvider getProvider() { |
| if (mProvider == null) { |
| mProvider = new MyFrameCallbackProvider(); |
| } |
| return mProvider; |
| } |
| |
| /** |
| * Register to get a callback on the next frame after the delay. |
| */ |
| public void addAnimationFrameCallback(final AnimationFrameCallback callback, long delay) { |
| if (mAnimationCallbacks.size() == 0) { |
| getProvider().postFrameCallback(mFrameCallback); |
| } |
| if (!mAnimationCallbacks.contains(callback)) { |
| mAnimationCallbacks.add(callback); |
| } |
| |
| if (delay > 0) { |
| mDelayedCallbackStartTime.put(callback, (SystemClock.uptimeMillis() + delay)); |
| } |
| } |
| |
| /** |
| * Register to get a one shot callback for frame commit timing. Frame commit timing is the |
| * time *after* traversals are done, as opposed to the animation frame timing, which is |
| * before any traversals. This timing can be used to adjust the start time of an animation |
| * when expensive traversals create big delta between the animation frame timing and the time |
| * that animation is first shown on screen. |
| * |
| * Note this should only be called when the animation has already registered to receive |
| * animation frame callbacks. This callback will be guaranteed to happen *after* the next |
| * animation frame callback. |
| */ |
| public void addOneShotCommitCallback(final AnimationFrameCallback callback) { |
| if (!mCommitCallbacks.contains(callback)) { |
| mCommitCallbacks.add(callback); |
| } |
| } |
| |
| /** |
| * Removes the given callback from the list, so it will no longer be called for frame related |
| * timing. |
| */ |
| public void removeCallback(AnimationFrameCallback callback) { |
| mCommitCallbacks.remove(callback); |
| mDelayedCallbackStartTime.remove(callback); |
| int id = mAnimationCallbacks.indexOf(callback); |
| if (id >= 0) { |
| mAnimationCallbacks.set(id, null); |
| mListDirty = true; |
| } |
| } |
| |
| private void doAnimationFrame(long frameTime) { |
| long currentTime = SystemClock.uptimeMillis(); |
| final int size = mAnimationCallbacks.size(); |
| for (int i = 0; i < size; i++) { |
| final AnimationFrameCallback callback = mAnimationCallbacks.get(i); |
| if (callback == null) { |
| continue; |
| } |
| if (isCallbackDue(callback, currentTime)) { |
| callback.doAnimationFrame(frameTime); |
| if (mCommitCallbacks.contains(callback)) { |
| getProvider().postCommitCallback(new Runnable() { |
| @Override |
| public void run() { |
| commitAnimationFrame(callback, getProvider().getFrameTime()); |
| } |
| }); |
| } |
| } |
| } |
| cleanUpList(); |
| } |
| |
| private void commitAnimationFrame(AnimationFrameCallback callback, long frameTime) { |
| if (!mDelayedCallbackStartTime.containsKey(callback) && |
| mCommitCallbacks.contains(callback)) { |
| callback.commitAnimationFrame(frameTime); |
| mCommitCallbacks.remove(callback); |
| } |
| } |
| |
| /** |
| * Remove the callbacks from mDelayedCallbackStartTime once they have passed the initial delay |
| * so that they can start getting frame callbacks. |
| * |
| * @return true if they have passed the initial delay or have no delay, false otherwise. |
| */ |
| private boolean isCallbackDue(AnimationFrameCallback callback, long currentTime) { |
| Long startTime = mDelayedCallbackStartTime.get(callback); |
| if (startTime == null) { |
| return true; |
| } |
| if (startTime < currentTime) { |
| mDelayedCallbackStartTime.remove(callback); |
| return true; |
| } |
| return false; |
| } |
| |
| /** |
| * Return the number of callbacks that have registered for frame callbacks. |
| */ |
| public static int getAnimationCount() { |
| AnimationHandler handler = sAnimatorHandler.get(); |
| if (handler == null) { |
| return 0; |
| } |
| return handler.getCallbackSize(); |
| } |
| |
| public static void setFrameDelay(long delay) { |
| getInstance().getProvider().setFrameDelay(delay); |
| } |
| |
| public static long getFrameDelay() { |
| return getInstance().getProvider().getFrameDelay(); |
| } |
| |
| void autoCancelBasedOn(ObjectAnimator objectAnimator) { |
| for (int i = mAnimationCallbacks.size() - 1; i >= 0; i--) { |
| AnimationFrameCallback cb = mAnimationCallbacks.get(i); |
| if (cb == null) { |
| continue; |
| } |
| if (objectAnimator.shouldAutoCancel(cb)) { |
| ((Animator) mAnimationCallbacks.get(i)).cancel(); |
| } |
| } |
| } |
| |
| private void cleanUpList() { |
| if (mListDirty) { |
| for (int i = mAnimationCallbacks.size() - 1; i >= 0; i--) { |
| if (mAnimationCallbacks.get(i) == null) { |
| mAnimationCallbacks.remove(i); |
| } |
| } |
| mListDirty = false; |
| } |
| } |
| |
| private int getCallbackSize() { |
| int count = 0; |
| int size = mAnimationCallbacks.size(); |
| for (int i = size - 1; i >= 0; i--) { |
| if (mAnimationCallbacks.get(i) != null) { |
| count++; |
| } |
| } |
| return count; |
| } |
| |
| /** |
| * Default provider of timing pulse that uses Choreographer for frame callbacks. |
| */ |
| private class MyFrameCallbackProvider implements AnimationFrameCallbackProvider { |
| |
| final Choreographer mChoreographer = Choreographer.getInstance(); |
| |
| @Override |
| public void postFrameCallback(Choreographer.FrameCallback callback) { |
| mChoreographer.postFrameCallback(callback); |
| } |
| |
| @Override |
| public void postCommitCallback(Runnable runnable) { |
| mChoreographer.postCallback(Choreographer.CALLBACK_COMMIT, runnable, null); |
| } |
| |
| @Override |
| public long getFrameTime() { |
| return mChoreographer.getFrameTime(); |
| } |
| |
| @Override |
| public long getFrameDelay() { |
| return Choreographer.getFrameDelay(); |
| } |
| |
| @Override |
| public void setFrameDelay(long delay) { |
| Choreographer.setFrameDelay(delay); |
| } |
| } |
| |
| /** |
| * Callbacks that receives notifications for animation timing and frame commit timing. |
| */ |
| interface AnimationFrameCallback { |
| /** |
| * Run animation based on the frame time. |
| * @param frameTime The frame start time, in the {@link SystemClock#uptimeMillis()} time |
| * base. |
| * @return if the animation has finished. |
| */ |
| boolean doAnimationFrame(long frameTime); |
| |
| /** |
| * This notifies the callback of frame commit time. Frame commit time is the time after |
| * traversals happen, as opposed to the normal animation frame time that is before |
| * traversals. This is used to compensate expensive traversals that happen as the |
| * animation starts. When traversals take a long time to complete, the rendering of the |
| * initial frame will be delayed (by a long time). But since the startTime of the |
| * animation is set before the traversal, by the time of next frame, a lot of time would |
| * have passed since startTime was set, the animation will consequently skip a few frames |
| * to respect the new frameTime. By having the commit time, we can adjust the start time to |
| * when the first frame was drawn (after any expensive traversals) so that no frames |
| * will be skipped. |
| * |
| * @param frameTime The frame time after traversals happen, if any, in the |
| * {@link SystemClock#uptimeMillis()} time base. |
| */ |
| void commitAnimationFrame(long frameTime); |
| } |
| |
| /** |
| * The intention for having this interface is to increase the testability of ValueAnimator. |
| * Specifically, we can have a custom implementation of the interface below and provide |
| * timing pulse without using Choreographer. That way we could use any arbitrary interval for |
| * our timing pulse in the tests. |
| * |
| * @hide |
| */ |
| public interface AnimationFrameCallbackProvider { |
| void postFrameCallback(Choreographer.FrameCallback callback); |
| void postCommitCallback(Runnable runnable); |
| long getFrameTime(); |
| long getFrameDelay(); |
| void setFrameDelay(long delay); |
| } |
| } |