1 /* 2 * Copyright 2019, 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 package com.android.managedprovisioning.common; 17 18 import android.animation.Animator; 19 import android.animation.AnimatorListenerAdapter; 20 import android.animation.AnimatorSet; 21 import android.animation.ValueAnimator; 22 import android.animation.ValueAnimator.AnimatorUpdateListener; 23 import android.annotation.TargetApi; 24 import android.view.View; 25 import java.util.ArrayList; 26 import java.util.List; 27 28 /** 29 * Performs fade out-fade in animations on a {@link View} list. 30 */ 31 public class CrossFadeHelper { 32 public interface Callback { fadeOutCompleted()33 void fadeOutCompleted(); fadeInCompleted()34 void fadeInCompleted(); 35 } 36 37 private final List<View> mViews; 38 private final int mDuration; 39 private final Callback mCallback; 40 private final ValueAnimator mFadeOutAnimator; 41 private final ValueAnimator mFadeInAnimator; 42 private final AnimatorSet mAnimatorSet; 43 44 private final AnimatorUpdateListener mAnimatorUpdateListener = new AnimatorUpdateListener() { 45 @Override 46 public void onAnimationUpdate(ValueAnimator animation) { 47 final float alpha = (float) animation.getAnimatedValue(); 48 for (View view : mViews) { 49 view.setAlpha(alpha); 50 } 51 } 52 }; 53 CrossFadeHelper(List<View> viewsToAnimate, int duration, Callback callback)54 public CrossFadeHelper(List<View> viewsToAnimate, int duration, Callback callback) { 55 mViews = new ArrayList<>(viewsToAnimate); 56 mDuration = duration; 57 mCallback = callback; 58 mFadeOutAnimator = getFadeOutAnimator(); 59 mFadeInAnimator = getFadeInAnimator(); 60 mAnimatorSet = new AnimatorSet(); 61 mAnimatorSet.playSequentially(mFadeOutAnimator, mFadeInAnimator); 62 } 63 start()64 public void start() { 65 mAnimatorSet.start(); 66 } 67 getFadeInAnimator()68 private ValueAnimator getFadeInAnimator() { 69 final ValueAnimator fadeInAnimator = ValueAnimator.ofFloat(0f, 1f); 70 fadeInAnimator.addUpdateListener(mAnimatorUpdateListener); 71 fadeInAnimator.setDuration(mDuration); 72 fadeInAnimator.addListener(new AnimatorListenerAdapter() { 73 @Override 74 public void onAnimationEnd(Animator animation) { 75 if (mCallback != null) { 76 mCallback.fadeInCompleted(); 77 } 78 } 79 }); 80 return fadeInAnimator; 81 } 82 getFadeOutAnimator()83 private ValueAnimator getFadeOutAnimator() { 84 final ValueAnimator fadeOutAnimator = ValueAnimator.ofFloat(1f, 0f); 85 fadeOutAnimator.addUpdateListener(mAnimatorUpdateListener); 86 fadeOutAnimator.setDuration(mDuration); 87 fadeOutAnimator.addListener(new AnimatorListenerAdapter() { 88 @Override 89 public void onAnimationEnd(Animator animation) { 90 if (mCallback != null) { 91 mCallback.fadeOutCompleted(); 92 } 93 } 94 }); 95 return fadeOutAnimator; 96 } 97 cleanup()98 public void cleanup() { 99 mFadeInAnimator.removeAllUpdateListeners(); 100 mFadeInAnimator.removeAllListeners(); 101 mFadeOutAnimator.removeAllUpdateListeners(); 102 mFadeOutAnimator.removeAllListeners(); 103 mAnimatorSet.cancel(); 104 mViews.clear(); 105 } 106 } 107