AnimatorSetCompat.java

/*
 * Copyright 2017 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.google.android.material.animation;

import android.animation.Animator;
import android.animation.AnimatorSet;
import android.animation.ValueAnimator;
import android.os.Build;
import androidx.annotation.NonNull;
import androidx.annotation.RequiresApi;
import androidx.annotation.RestrictTo;
import androidx.annotation.RestrictTo.Scope;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

/**
 * Compatibility utils for {@link android.animation.AnimatorSet}.
 *
 * @hide
 */
@RestrictTo(Scope.LIBRARY_GROUP)
public class AnimatorSetCompat {

  /** Sets up this AnimatorSet to play all of the supplied animations at the same time. */
  public static void playTogether(@NonNull AnimatorSet animatorSet, @NonNull List<Animator> items) {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
      Api23Impl.playTogether(animatorSet, items);
    } else {
      Api21Impl.playTogether(animatorSet, items);
    }
  }

  @RequiresApi(Build.VERSION_CODES.M)
  static class Api23Impl {
    static void playTogether(@NonNull AnimatorSet animatorSet, @NonNull Collection<Animator> items) {
      animatorSet.playTogether(items);
    }
  }

  static class Api21Impl {
    static void playTogether(@NonNull AnimatorSet animatorSet, @NonNull Collection<Animator> items) {
      // Fix for pre-M bug where animators with start delay are not played correctly in an
      // AnimatorSet.
      long totalDuration = 0;
      for (Animator animator : items) {
        totalDuration = Math.max(totalDuration, animator.getStartDelay() + animator.getDuration());
      }
      Animator fix = ValueAnimator.ofInt(0, 0);
      fix.setDuration(totalDuration);

      List<Animator> animators = new ArrayList<>(items.size() + 1);
      animators.add(fix);
      animators.addAll(items);
      animatorSet.playTogether(animators);
    }
  }
}