1 /*
2  * Copyright (C) 2016 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.systemui.statusbar.notification;
18 
19 import android.animation.Animator;
20 import android.animation.AnimatorListenerAdapter;
21 import android.animation.PropertyValuesHolder;
22 import android.animation.ValueAnimator;
23 import android.util.Property;
24 import android.view.View;
25 import android.view.animation.Interpolator;
26 
27 import com.android.systemui.Interpolators;
28 import com.android.systemui.statusbar.stack.AnimationFilter;
29 import com.android.systemui.statusbar.stack.AnimationProperties;
30 import com.android.systemui.statusbar.stack.ViewState;
31 
32 /**
33  * An animator to animate properties
34  */
35 public class PropertyAnimator {
36 
startAnimation(final T view, AnimatableProperty animatableProperty, float newEndValue, AnimationProperties properties)37     public static <T extends View> void startAnimation(final T view,
38             AnimatableProperty animatableProperty, float newEndValue,
39             AnimationProperties properties) {
40         Property<T, Float> property = animatableProperty.getProperty();
41         int animationStartTag = animatableProperty.getAnimationStartTag();
42         int animationEndTag = animatableProperty.getAnimationEndTag();
43         Float previousStartValue = ViewState.getChildTag(view, animationStartTag);
44         Float previousEndValue = ViewState.getChildTag(view, animationEndTag);
45         if (previousEndValue != null && previousEndValue == newEndValue) {
46             return;
47         }
48         int animatorTag = animatableProperty.getAnimatorTag();
49         ValueAnimator previousAnimator = ViewState.getChildTag(view, animatorTag);
50         AnimationFilter filter = properties.getAnimationFilter();
51         if (!filter.shouldAnimateProperty(property)) {
52             // just a local update was performed
53             if (previousAnimator != null) {
54                 // we need to increase all animation keyframes of the previous animator by the
55                 // relative change to the end value
56                 PropertyValuesHolder[] values = previousAnimator.getValues();
57                 float relativeDiff = newEndValue - previousEndValue;
58                 float newStartValue = previousStartValue + relativeDiff;
59                 values[0].setFloatValues(newStartValue, newEndValue);
60                 view.setTag(animationStartTag, newStartValue);
61                 view.setTag(animationEndTag, newEndValue);
62                 previousAnimator.setCurrentPlayTime(previousAnimator.getCurrentPlayTime());
63                 return;
64             } else {
65                 // no new animation needed, let's just apply the value
66                 property.set(view, newEndValue);
67                 return;
68             }
69         }
70 
71         Float currentValue = property.get(view);
72         ValueAnimator animator = ValueAnimator.ofFloat(currentValue, newEndValue);
73         animator.addUpdateListener(
74                 animation -> property.set(view, (Float) animation.getAnimatedValue()));
75         Interpolator customInterpolator = properties.getCustomInterpolator(view, property);
76         Interpolator interpolator =  customInterpolator != null ? customInterpolator
77                 : Interpolators.FAST_OUT_SLOW_IN;
78         animator.setInterpolator(interpolator);
79         long newDuration = ViewState.cancelAnimatorAndGetNewDuration(properties.duration,
80                 previousAnimator);
81         animator.setDuration(newDuration);
82         if (properties.delay > 0 && (previousAnimator == null
83                 || previousAnimator.getAnimatedFraction() == 0)) {
84             animator.setStartDelay(properties.delay);
85         }
86         AnimatorListenerAdapter listener = properties.getAnimationFinishListener();
87         if (listener != null) {
88             animator.addListener(listener);
89         }
90         // remove the tag when the animation is finished
91         animator.addListener(new AnimatorListenerAdapter() {
92             @Override
93             public void onAnimationEnd(Animator animation) {
94                 view.setTag(animatorTag, null);
95                 view.setTag(animationStartTag, null);
96                 view.setTag(animationEndTag, null);
97             }
98         });
99         ViewState.startAnimator(animator, listener);
100         view.setTag(animatorTag, animator);
101         view.setTag(animationStartTag, currentValue);
102         view.setTag(animationEndTag, newEndValue);
103     }
104 
105     public interface AnimatableProperty {
getAnimationStartTag()106         int getAnimationStartTag();
getAnimationEndTag()107         int getAnimationEndTag();
getAnimatorTag()108         int getAnimatorTag();
getProperty()109         Property getProperty();
110     }
111 }
112