content: /*
   * Copyright (C) 2014 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 android.view;
  
  import android.animation.Animator;
  import android.animation.Animator.AnimatorListener;
  import android.animation.RevealAnimator;
  
  /**
   * Defines common utilities for working with View's animations.
   *
   */
  public final class ViewAnimationUtils {
      private ViewAnimationUtils() {}
      /**
       * Returns an Animator which can animate a clipping circle.
       * <p>
       * Any shadow cast by the View will respect the circular clip from this animator.
       * <p>
       * Only a single non-rectangular clip can be applied on a View at any time.
       * Views clipped by a circular reveal animation take priority over
       * {@link View#setClipToOutline(boolean) View Outline clipping}.
       * <p>
       * Note that the animation returned here is a one-shot animation. It cannot
       * be re-used, and once started it cannot be paused or resumed. It is also
       * an asynchronous animation that automatically runs off of the UI thread.
       * As a result {@link AnimatorListener#onAnimationEnd(Animator)}
       * will occur after the animation has ended, but it may be delayed depending
       * on thread responsiveness.
       * <p>
       * Note that if any start delay is set on the reveal animator, the start radius
       * will not be applied to the reveal circle until the start delay has passed.
       * If it's desired to set a start radius on the reveal circle during the start
       * delay, one workaround could be adding an animator with the same start and
       * end radius. For example:
       * <pre><code>
       * public static Animator createRevealWithDelay(View view, int centerX, int centerY, float startRadius, float endRadius) {
       *     Animator delayAnimator = ViewAnimationUtils.createCircularReveal(view, centerX, centerY, startRadius, startRadius);
       *     delayAnimator.setDuration(delayTimeMS);
       *     Animator revealAnimator = ViewAnimationUtils.createCircularReveal(view, centerX, centerY, startRadius, endRadius);
       *     AnimatorSet set = new AnimatorSet();
       *     set.playSequentially(delayAnimator, revealAnimator);
       *     return set;
       * }
       * </code></pre>
       *
       * @param view The View will be clipped to the animating circle.
       * @param centerX The x coordinate of the center of the animating circle, relative to
       *                <code>view</code>.
       * @param centerY The y coordinate of the center of the animating circle, relative to
       *                <code>view</code>.
       * @param startRadius The starting radius of the animating circle.
       * @param endRadius The ending radius of the animating circle.
       */
      public static Animator createCircularReveal(View view,
              int centerX,  int centerY, float startRadius, float endRadius) {
          return new RevealAnimator(view, centerX, centerY, startRadius, endRadius);
      }
  }
  