倒计时五种方法，方法一：Timer与TimerTask（Java实现）

1. public class timerTask extends Activity{    
2.    
3.     private int recLen = 11;    
4.     private TextView txtView;    
5.     Timer timer = new Timer();    
6.    
7.     public void onCreate(Bundle savedInstanceState){    
8.         super.onCreate(savedInstanceState);    
9.             
10.         setContentView(R.layout.timertask);    
11.         txtView = (TextView)findViewById(R.id.txttime);    
12.             
13.         timer.schedule(task, 1000, 1000);       // timeTask    
14.     }       
15.    
16.     TimerTask task = new TimerTask() {    
17.         @Override    
18.         public void run() {    
19.    
20.             runOnUiThread(new Runnable() {      // UI thread    
21.                 @Override    
22.                 public void run() {    
23.                     recLen--;    
24.                     txtView.setText(""+recLen);    
25.                     if(recLen < 0){    
26.                         timer.cancel();    
27.                         txtView.setVisibility(View.GONE);    
28.                     }    
29.                 }    
30.             });    
31.         }    
32.     };    
33. }