1 /* 2 * Copyright (C) 2013 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.android.launcher2; 18 19 import android.animation.Animator; 20 import android.animation.AnimatorListenerAdapter; 21 import android.animation.ValueAnimator; 22 import android.util.Log; 23 import android.view.View; 24 import android.view.ViewPropertyAnimator; 25 import android.view.ViewTreeObserver; 26 27 /* 28 * This is a helper class that listens to updates from the corresponding animation. 29 * For the first two frames, it adjusts the current play time of the animation to 30 * prevent jank at the beginning of the animation 31 */ 32 public class FirstFrameAnimatorHelper extends AnimatorListenerAdapter 33 implements ValueAnimator.AnimatorUpdateListener { 34 private static final boolean DEBUG = false; 35 private static final int MAX_DELAY = 1000; 36 private static final int IDEAL_FRAME_DURATION = 16; 37 private View mTarget; 38 private long mStartFrame; 39 private long mStartTime = -1; 40 private boolean mHandlingOnAnimationUpdate; 41 private boolean mAdjustedSecondFrameTime; 42 43 private static ViewTreeObserver.OnDrawListener sGlobalDrawListener; 44 private static long sGlobalFrameCounter; 45 private static boolean sVisible; 46 FirstFrameAnimatorHelper(ValueAnimator animator, View target)47 public FirstFrameAnimatorHelper(ValueAnimator animator, View target) { 48 mTarget = target; 49 animator.addUpdateListener(this); 50 } 51 FirstFrameAnimatorHelper(ViewPropertyAnimator vpa, View target)52 public FirstFrameAnimatorHelper(ViewPropertyAnimator vpa, View target) { 53 mTarget = target; 54 vpa.setListener(this); 55 } 56 57 // only used for ViewPropertyAnimators onAnimationStart(Animator animation)58 public void onAnimationStart(Animator animation) { 59 final ValueAnimator va = (ValueAnimator) animation; 60 va.addUpdateListener(FirstFrameAnimatorHelper.this); 61 onAnimationUpdate(va); 62 } 63 setIsVisible(boolean visible)64 public static void setIsVisible(boolean visible) { 65 sVisible = visible; 66 } 67 initializeDrawListener(View view)68 public static void initializeDrawListener(View view) { 69 if (sGlobalDrawListener != null) { 70 view.getViewTreeObserver().removeOnDrawListener(sGlobalDrawListener); 71 } 72 sGlobalDrawListener = new ViewTreeObserver.OnDrawListener() { 73 private long mTime = System.currentTimeMillis(); 74 public void onDraw() { 75 sGlobalFrameCounter++; 76 if (DEBUG) { 77 long newTime = System.currentTimeMillis(); 78 Log.d("FirstFrameAnimatorHelper", "TICK " + (newTime - mTime)); 79 mTime = newTime; 80 } 81 } 82 }; 83 view.getViewTreeObserver().addOnDrawListener(sGlobalDrawListener); 84 sVisible = true; 85 } 86 onAnimationUpdate(final ValueAnimator animation)87 public void onAnimationUpdate(final ValueAnimator animation) { 88 final long currentTime = System.currentTimeMillis(); 89 if (mStartTime == -1) { 90 mStartFrame = sGlobalFrameCounter; 91 mStartTime = currentTime; 92 } 93 94 boolean isFinalFrame = Float.compare(1f, animation.getAnimatedFraction()) == 0; 95 96 if (!mHandlingOnAnimationUpdate && 97 sVisible && 98 // If the current play time exceeds the duration, or the animated fraction is 1, 99 // the animation will get finished, even if we call setCurrentPlayTime -- therefore 100 // don't adjust the animation in that case 101 animation.getCurrentPlayTime() < animation.getDuration() && !isFinalFrame) { 102 mHandlingOnAnimationUpdate = true; 103 long frameNum = sGlobalFrameCounter - mStartFrame; 104 // If we haven't drawn our first frame, reset the time to t = 0 105 // (give up after MAX_DELAY ms of waiting though - might happen, for example, if we 106 // are no longer in the foreground and no frames are being rendered ever) 107 if (frameNum == 0 && currentTime < mStartTime + MAX_DELAY) { 108 // The first frame on animations doesn't always trigger an invalidate... 109 // force an invalidate here to make sure the animation continues to advance 110 mTarget.getRootView().invalidate(); 111 animation.setCurrentPlayTime(0); 112 113 // For the second frame, if the first frame took more than 16ms, 114 // adjust the start time and pretend it took only 16ms anyway. This 115 // prevents a large jump in the animation due to an expensive first frame 116 } else if (frameNum == 1 && currentTime < mStartTime + MAX_DELAY && 117 !mAdjustedSecondFrameTime && 118 currentTime > mStartTime + IDEAL_FRAME_DURATION) { 119 animation.setCurrentPlayTime(IDEAL_FRAME_DURATION); 120 mAdjustedSecondFrameTime = true; 121 } else { 122 if (frameNum > 1) { 123 mTarget.post(new Runnable() { 124 public void run() { 125 animation.removeUpdateListener(FirstFrameAnimatorHelper.this); 126 } 127 }); 128 } 129 if (DEBUG) print(animation); 130 } 131 mHandlingOnAnimationUpdate = false; 132 } else { 133 if (DEBUG) print(animation); 134 } 135 } 136 print(ValueAnimator animation)137 public void print(ValueAnimator animation) { 138 float flatFraction = animation.getCurrentPlayTime() / (float) animation.getDuration(); 139 Log.d("FirstFrameAnimatorHelper", sGlobalFrameCounter + 140 "(" + (sGlobalFrameCounter - mStartFrame) + ") " + mTarget + " dirty? " + 141 mTarget.isDirty() + " " + flatFraction + " " + this + " " + animation); 142 } 143 } 144