content: /*
   * Copyright (C) 2018 The Android Open Source Project
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package com.android.quickstep.util;
  
  import android.animation.ValueAnimator;
  import android.view.animation.Interpolator;
  
  import java.util.ArrayList;
  
  /**
   * Utility class to update multiple values with different interpolators and durations during
   * the same animation.
   */
  public abstract class MultiValueUpdateListener implements ValueAnimator.AnimatorUpdateListener {
  
      private final ArrayList<FloatProp> mAllProperties = new ArrayList<>();
  
      @Override
      public final void onAnimationUpdate(ValueAnimator animator) {
          final float percent = animator.getAnimatedFraction();
          final float currentPlayTime = percent * animator.getDuration();
  
          for (int i = mAllProperties.size() - 1; i >= 0; i--) {
              FloatProp prop = mAllProperties.get(i);
              float time = Math.max(0, currentPlayTime - prop.mDelay);
              float newPercent = Math.min(1f, time / prop.mDuration);
              newPercent = prop.mInterpolator.getInterpolation(newPercent);
              prop.value = prop.mEnd * newPercent + prop.mStart * (1 - newPercent);
          }
          onUpdate(percent);
      }
  
      public abstract void onUpdate(float percent);
  
      public final class FloatProp {
  
          public float value;
  
          private final float mStart;
          private final float mEnd;
          private final float mDelay;
          private final float mDuration;
          private final Interpolator mInterpolator;
  
          public FloatProp(float start, float end, float delay, float duration, Interpolator i) {
              value = mStart = start;
              mEnd = end;
              mDelay = delay;
              mDuration = duration;
              mInterpolator = i;
  
              mAllProperties.add(this);
          }
      }
  }
  