android-handler基本使用

Handler的使用，利用Handler来更新ui界面

例画圆移动：

1. public class TestHandler extends Activity {  
2.      protected static final int GUIUPDATEIDENTIFIER = 0x101;   
3.        
4.      Thread myRefreshThread = null;   
5.      BounceView myBounceView = null;   
6.    
7.      Handler myHandler = new Handler() {  
8.           public void handleMessage(Message msg) {   
9.                switch (msg.what) {   
10.                     case TestHandler.GUIUPDATEIDENTIFIER:   
11.                          myBounceView.invalidate();  
12.                          break;   
13.                }   
14.                super.handleMessage(msg);   
15.           }   
16.      };  
17.      public void onCreate(Bundle savedInstanceState) {   
18.           super.onCreate(savedInstanceState);   
19.           this.requestWindowFeature(Window.FEATURE_NO_TITLE);   
20.    
21.           this.myBounceView = new BounceView(this);  
22.           this.setContentView(this.myBounceView);   
23.           new Thread(new myThread()).start();  
24.      }   
25.    
26.      class myThread implements Runnable {   
27.           public void run() {  
28.                while (!Thread.currentThread().isInterrupted()) {    
29.                        
30.                     Message message = new Message();   
31.                     message.what = TestHandler.GUIUPDATEIDENTIFIER;   
32.                       
33.                     TestHandler.this.myHandler.sendMessage(message);   
34.                     try {   
35.                          Thread.sleep(100);    
36.                     } catch (InterruptedException e) {   
37.                          Thread.currentThread().interrupt();   
38.                     }   
39.                }   
40.           }   
41.      }   
42. }