Android消息处理机制②

1 public class Activity2 extends Activity implements OnClickListener{
 2        Button button = null;
 3        TextView text = null;
 4        MyHandler mHandler = null;
 5        Thread thread ;
 6        @Override
 7        protected void onCreate(Bundle savedInstanceState) {
 8               super.onCreate(savedInstanceState);
 9               setContentView(R.layout.activity1);        
10               button = (Button)findViewById(R.id.btn);
11               button.setOnClickListener(this);
12               text = (TextView)findViewById(R.id.content);
13        }
14        public void onClick(View v) {
15               switch (v.getId()) {
16               case R.id.btn:
17                      thread = new MyThread();
18                      thread.start();
19                      break;
20               }            
21        }     
22        private class MyHandler extends Handler{             
23               public MyHandler(Looper looper){
24                      super(looper);
25               }
26               @Override
27               public void handleMessage(Message msg) {//处理消息
28                       text.setText(msg.obj.toString());
29               }            
30        }
31        private class MyThread extends Thread{
32               @Override
33               public void run() {
34                      Looper curLooper = Looper.myLooper();
35                      Looper mainLooper = Looper.getMainLooper();
36                      String msg ;
37                      if(curLooper==null){
38                             mHandler = new MyHandler(mainLooper);
39                             msg = "curLooper is null";
40                      }else{
41                             mHandler = new MyHandler(curLooper);
42                             msg = "This is curLooper";
43                      }
44                      mHandler.removeMessages(0);
45                      Message m = mHandler.obtainMessage(1, 1, 1, msg);
46                      mHandler.sendMessage(m);
47               }            
48        }
49 }