RadialTransformationActivity.java 文件源码

@Override public boolean onSingleTapUp(MotionEvent e) {
  View nextView = getNext();
  nextView.bringToFront();
  nextView.setVisibility(View.VISIBLE);

  final float finalRadius =
      (float) Math.hypot(nextView.getWidth() / 2f, nextView.getHeight() / 2f) + hypo(
          nextView, e);

  Animator revealAnimator =
      ViewAnimationUtils.createCircularReveal(nextView, (int) e.getX(), (int) e.getY(), 0,
          finalRadius, View.LAYER_TYPE_HARDWARE);

  revealAnimator.setDuration(MainActivity.SLOW_DURATION);
  revealAnimator.setInterpolator(new FastOutLinearInInterpolator());
  revealAnimator.start();

  return true;
}