FabTransformationScrimBehavior.java 文件源码

private void createScrimAnimation(
    View child,
    boolean expanded,
    boolean currentlyAnimating,
    List<Animator> animations,
    List<AnimatorListener> unusedListeners) {
  MotionTiming timing = expanded ? expandTiming : collapseTiming;

  Animator animator;
  if (expanded) {
    if (!currentlyAnimating) {
      child.setAlpha(0f);
    }
    animator = ObjectAnimator.ofFloat(child, View.ALPHA, 1f);
  } else {
    animator = ObjectAnimator.ofFloat(child, View.ALPHA, 0f);
  }

  timing.apply(animator);
  animations.add(animator);
}