最近再做一個教育類的項目，

Android實現(xiàn)心跳的效果

    其實實現(xiàn)過程也不難，大致就是對一個視圖控件添加一個圓形的背景，然后該視圖進(jìn)行動畫處理，膨脹的同時，透明度增大，收縮的同時，透明度降低。

    我在例子中是使用了TextView，所以首先對TextView添加一個圓形的背景：

<shape android:shape="oval" xmlns:android="http://schemas.android.com/apk/res/android"><size android:height="90dp" android:width="90dp"><solid android:color="@color/color_space_studytools_red"><corners android:radius="180dip"><padding android:bottom="4dip" android:left="4dip" android:right="4dip" android:top="4dip"></padding></corners></solid></size></shape>

    然后為TextView添加動畫，包括調(diào)整大小的ScaleAnimation和調(diào)整透明度的AlphaAnimation。調(diào)整大小有兩個部分，膨脹和收縮。在膨脹完畢后馬上收縮，也就是對膨脹的動畫進(jìn)行監(jiān)聽，在onAnimationEnd()方法里面進(jìn)行收縮，

// 按鈕模擬心臟跳動	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);// 動畫結(jié)束時重新開始，實現(xiàn)心跳的View			}		});		heartbeatView.startAnimation(swellAnimationSet);	}

    心跳的效果是要不停地膨脹和收縮，所以要開一個線程來處理，每當(dāng)收縮完畢后重新膨脹，

電腦資料

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的生命周期結(jié)合，對線程進(jìn)行開始和結(jié)束。

private Thread heartbeatThread;	/**	 * 開始心跳	 */	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();	}