1 /* 2 * Copyright (C) 2017 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.quickstep; 17 18 import android.animation.Animator; 19 import android.animation.AnimatorListenerAdapter; 20 import android.animation.ObjectAnimator; 21 import android.util.FloatProperty; 22 23 /** 24 * A mutable float which allows animating the value 25 */ 26 public class AnimatedFloat { 27 28 public static final FloatProperty<AnimatedFloat> VALUE = 29 new FloatProperty<AnimatedFloat>("value") { 30 @Override 31 public void setValue(AnimatedFloat obj, float v) { 32 obj.updateValue(v); 33 } 34 35 @Override 36 public Float get(AnimatedFloat obj) { 37 return obj.value; 38 } 39 }; 40 41 private static final Runnable NO_OP = () -> { }; 42 43 private final Runnable mUpdateCallback; 44 private ObjectAnimator mValueAnimator; 45 46 public float value; 47 AnimatedFloat()48 public AnimatedFloat() { 49 this(NO_OP); 50 } 51 AnimatedFloat(Runnable updateCallback)52 public AnimatedFloat(Runnable updateCallback) { 53 mUpdateCallback = updateCallback; 54 } 55 animateToValue(float start, float end)56 public ObjectAnimator animateToValue(float start, float end) { 57 cancelAnimation(); 58 mValueAnimator = ObjectAnimator.ofFloat(this, VALUE, start, end); 59 mValueAnimator.addListener(new AnimatorListenerAdapter() { 60 @Override 61 public void onAnimationEnd(Animator animator) { 62 if (mValueAnimator == animator) { 63 mValueAnimator = null; 64 } 65 } 66 }); 67 return mValueAnimator; 68 } 69 70 /** 71 * Changes the value and calls the callback. 72 * Note that the value can be directly accessed as well to avoid notifying the callback. 73 */ updateValue(float v)74 public void updateValue(float v) { 75 if (Float.compare(v, value) != 0) { 76 value = v; 77 mUpdateCallback.run(); 78 } 79 } 80 cancelAnimation()81 public void cancelAnimation() { 82 if (mValueAnimator != null) { 83 mValueAnimator.cancel(); 84 } 85 } 86 finishAnimation()87 public void finishAnimation() { 88 if (mValueAnimator != null && mValueAnimator.isRunning()) { 89 mValueAnimator.end(); 90 } 91 } 92 getCurrentAnimation()93 public ObjectAnimator getCurrentAnimation() { 94 return mValueAnimator; 95 } 96 } 97