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 FloatProperty<AnimatedFloat> VALUE = new FloatProperty<AnimatedFloat>("value") { 29 @Override 30 public void setValue(AnimatedFloat obj, float v) { 31 obj.updateValue(v); 32 } 33 34 @Override 35 public Float get(AnimatedFloat obj) { 36 return obj.value; 37 } 38 }; 39 40 private final Runnable mUpdateCallback; 41 private ObjectAnimator mValueAnimator; 42 43 public float value; 44 AnimatedFloat(Runnable updateCallback)45 public AnimatedFloat(Runnable updateCallback) { 46 mUpdateCallback = updateCallback; 47 } 48 animateToValue(float start, float end)49 public ObjectAnimator animateToValue(float start, float end) { 50 cancelAnimation(); 51 mValueAnimator = ObjectAnimator.ofFloat(this, VALUE, start, end); 52 mValueAnimator.addListener(new AnimatorListenerAdapter() { 53 @Override 54 public void onAnimationEnd(Animator animator) { 55 if (mValueAnimator == animator) { 56 mValueAnimator = null; 57 } 58 } 59 }); 60 return mValueAnimator; 61 } 62 63 /** 64 * Changes the value and calls the callback. 65 * Note that the value can be directly accessed as well to avoid notifying the callback. 66 */ updateValue(float v)67 public void updateValue(float v) { 68 if (Float.compare(v, value) != 0) { 69 value = v; 70 mUpdateCallback.run(); 71 } 72 } 73 cancelAnimation()74 public void cancelAnimation() { 75 if (mValueAnimator != null) { 76 mValueAnimator.cancel(); 77 } 78 } 79 finishAnimation()80 public void finishAnimation() { 81 if (mValueAnimator != null && mValueAnimator.isRunning()) { 82 mValueAnimator.end(); 83 } 84 } 85 getCurrentAnimation()86 public ObjectAnimator getCurrentAnimation() { 87 return mValueAnimator; 88 } 89 } 90