最近再做一个教育类的项目。在做一些学习工具的时候，美工提出了一些要求，大致如下：

其实实现过程也不难，大致就是对一个视图控件添加一个圆形的背景，然后该视图进行动画处理，膨胀的同时，透明度增大，收缩的同时，透明度降低。

我在例子中是使用了TextView，所以首先对TextView添加一个圆形的背景：

android:shape="oval" >

android:height="90dp"

android:width="90dp" />

android:bottom="4dip"

android:left="4dip"

android:right="4dip"

android:top="4dip" />

然后为TextView添加动画，包括调整大小的ScaleAnimation和调整透明度的AlphaAnimation。调整大小有两个部分，膨胀和收缩。在膨胀完毕后马上收缩，也就是对膨胀的动画进行监听，在onAnimationEnd()方法里面进行收缩，

// 按钮模拟心脏跳动

private void playHeartbeatAnimation(final View heartbeatView) {

AnimationSet swellAnimationSet = new AnimationSet(true);

swellAnimationSet.addAnimation(new ScaleAnimation(1.0f, 1.8f, 1.0f, 1.8f, Animation.RELATIVE_TO_SELF, 0.5f,

Animation.RELATIVE_TO_SELF, 0.5f));

swellAnimationSet.addAnimation(new AlphaAnimation(1.0f, 0.3f));

swellAnimationSet.setDuration(500);

swellAnimationSet.setInterpolator(new AccelerateInterpolator());

swellAnimationSet.setFillAfter(true);

swellAnimationSet.setAnimationListener(new AnimationListener() {

@Override

public void onAnimationStart(Animation animation) {

}

@Override

public void onAnimationRepeat(Animation animation) {

}

@Override

public void onAnimationEnd(Animation animation) {

AnimationSet shrinkAnimationSet = new AnimationSet(true);

shrinkAnimationSet.addAnimation(new ScaleAnimation(1.8f, 1.0f, 1.8f, 1.0f, Animation.RELATIVE_TO_SELF,

0.5f, Animation.RELATIVE_TO_SELF, 0.5f));

shrinkAnimationSet.addAnimation(new AlphaAnimation(0.3f, 1.0f));

shrinkAnimationSet.setDuration(1000);

shrinkAnimationSet.setInterpolator(new DecelerateInterpolator());

shrinkAnimationSet.setFillAfter(false);

heartbeatView.startAnimation(shrinkAnimationSet);// 动画结束时重新开始，实现心跳的View

}

});

heartbeatView.startAnimation(swellAnimationSet);

}

心跳的效果是要不停地膨胀和收缩，所以要开一个线程来处理，每当收缩完毕后重新膨胀。

private class HeatbeatThread extends Thread {

public void run() {

try {

sleep(100);

} catch (InterruptedException e1) {

e1.printStackTrace();

}

while (true) {

runOnUiThread(new Runnable() {

public void run() {

for (View view : heartbeatViews) {

playHeartbeatAnimation(view);

}

}

});

try {

Thread.sleep(1500);

} catch (InterruptedException e) {

e.printStackTrace();

}

}

};

}

最后和Activity的生命周期结合，对线程进行开始和结束。

private Thread heartbeatThread;

/**

* 开始心跳

*/

private void startHeartBeat() {

if (heartbeatThread == null) {

heartbeatThread = new HeatbeatThread();

}

if (!heartbeatThread.isAlive()) {

heartbeatThread.start();

}

}

/**

* 停止心跳

*/

private void stopHeartBeat() {

if (heartbeatThread != null && heartbeatThread.isInterrupted()) {

heartbeatThread.interrupt();

heartbeatThread = null;

System.gc();

}

}

@Override

protected void onResume() {

super.onResume();

startHeartBeat();

}

@Override

protected void onPause() {

super.onPause();

stopHeartBeat();

}

原文：http://blog.csdn.net/u014375869/article/details/46638061