content: package com.rsen.github.easyandroidanimations;
  
  import android.animation.Animator;
  import android.animation.AnimatorListenerAdapter;
  import android.animation.AnimatorSet;
  import android.animation.ObjectAnimator;
  import android.animation.TimeInterpolator;
  import android.view.View;
  import android.view.ViewGroup;
  import android.view.animation.AccelerateDecelerateInterpolator;
  
  /**
   * This animation causes the view to shake from left to right for a customizable
   * number of times before returning to its original position.
   * 
   * @author SiYao
   * 
   */
  public class ShakeAnimation extends Animation {
  
  	float shakeDistance;
  	int numOfShakes, shakeCount = 0;
  	TimeInterpolator interpolator;
  	long duration;
  	AnimationListener listener;
  
  	/**
  	 * This animation causes the view to shake from left to right for a
  	 * customizable number of times before returning to its original position.
  	 * 
  	 * @param view
  	 *            The view to be animated.
  	 */
  	public ShakeAnimation(View view) {
  		this.view = view;
  		shakeDistance = 20;
  		numOfShakes = 2;
  		interpolator = new AccelerateDecelerateInterpolator();
  		duration = DURATION_LONG;
  		listener = null;
  	}
  
  	@Override
  	public void animate() {
  		long singleShakeDuration = duration / numOfShakes / 2;
  		if (singleShakeDuration == 0)
  			singleShakeDuration = 1;
  		final AnimatorSet shakeAnim = new AnimatorSet();
  		shakeAnim
  				.playSequentially(ObjectAnimator.ofFloat(view,
  						View.TRANSLATION_X, shakeDistance), ObjectAnimator
  						.ofFloat(view, View.TRANSLATION_X, -shakeDistance),
  						ObjectAnimator.ofFloat(view, View.TRANSLATION_X,
  								shakeDistance), ObjectAnimator.ofFloat(view,
  								View.TRANSLATION_X, 0));
  		shakeAnim.setInterpolator(interpolator);
  		shakeAnim.setDuration(singleShakeDuration);
  
  		ViewGroup parentView = (ViewGroup) view.getParent(), rootView = (ViewGroup) view
  				.getRootView();
  		while (!parentView.equals(rootView)) {
  			parentView.setClipChildren(false);
  			parentView = (ViewGroup) parentView.getParent();
  		}
  		rootView.setClipChildren(false);
  		shakeAnim.addListener(new AnimatorListenerAdapter() {
  
  			@Override
  			public void onAnimationEnd(Animator animation) {
  				shakeCount++;
  				if (shakeCount == numOfShakes) {
  					if (getListener() != null) {
  						getListener().onAnimationEnd(ShakeAnimation.this);
  					}
  				} else {
  					shakeAnim.start();
  				}
  			}
  		});
  		shakeAnim.start();
  	}
  
  	/**
  	 * @return The maximum shake distance.
  	 */
  	public float getShakeDistance() {
  		return shakeDistance;
  	}
  
  	/**
  	 * @param shakeDistance
  	 *            The maximum shake distance to set.
  	 * @return This object, allowing calls to methods in this class to be
  	 *         chained.
  	 */
  	public ShakeAnimation setShakeDistance(float shakeDistance) {
  		this.shakeDistance = shakeDistance;
  		return this;
  	}
  
  	/**
  	 * @return The number of shakes.
  	 */
  	public int getNumOfShakes() {
  		return numOfShakes;
  	}
  
  	/**
  	 * @param numOfShakes
  	 *            The number of shakes to set.
  	 * @return This object, allowing calls to methods in this class to be
  	 *         chained.
  	 */
  	public ShakeAnimation setNumOfShakes(int numOfShakes) {
  		this.numOfShakes = numOfShakes;
  		return this;
  	}
  
  	/**
  	 * @return The interpolator of the entire animation.
  	 */
  	public TimeInterpolator getInterpolator() {
  		return interpolator;
  	}
  
  	/**
  	 * @param interpolator
  	 *            The interpolator of the entire animation to set.
  	 */
  	public ShakeAnimation setInterpolator(TimeInterpolator interpolator) {
  		this.interpolator = interpolator;
  		return this;
  	}
  
  	/**
  	 * @return The duration of the entire animation.
  	 */
  	public long getDuration() {
  		return duration;
  	}
  
  	/**
  	 * @param duration
  	 *            The duration of the entire animation to set.
  	 * @return This object, allowing calls to methods in this class to be
  	 *         chained.
  	 */
  	public ShakeAnimation setDuration(long duration) {
  		this.duration = duration;
  		return this;
  	}
  
  	/**
  	 * @return The listener for the end of the animation.
  	 */
  	public AnimationListener getListener() {
  		return listener;
  	}
  
  	/**
  	 * @param listener
  	 *            The listener to set for the end of the animation.
  	 * @return This object, allowing calls to methods in this class to be
  	 *         chained.
  	 */
  	public ShakeAnimation setListener(AnimationListener listener) {
  		this.listener = listener;
  		return this;
  	}
  
  }
  