android handler 学习

package pos.app;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.Button;

public class Android extends Activity {
	/** Called when the activity is first created. */
	@Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.home);
       
        Button helpButton =(Button) findViewById(R.id.login_help);
        
     
        helpButton.setOnClickListener(new Button.OnClickListener(){

			@Override
			public void onClick(View v) {
				
				Intent intent  = new Intent(AndroidApp.this,MyHandlerActivity.class);
				startActivity(intent);
			}
        	
        });
	}
}

package pos.app;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.os.Message;
import android.util.Log;
import android.widget.Button;

public class MyHandlerActivity extends Activity {

Button button;
MyHandler myHandler;

public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);

setContentView(R.layout.home);
setTitle("My Handler Activity");
button = (Button)findViewById(R.id.login_help);

myHandler = new MyHandler();

MyThread m = new MyThread();
new Thread(m).start();
}


class MyHandler extends Handler {

public MyHandler(){

}

public MyHandler( Looper L){
super(L);
}

@Override
public void handleMessage(Message msg){
Log.v("MyHandler", "handleMessage....");
super.handleMessage(msg);
Bundle bundle  = msg.getData();
String text = bundle.getString("text");
MyHandlerActivity.this.button.setText(text);

}
}

class MyThread implements Runnable  {

@Override
public void run() {

try{
Thread.sleep(1000);
}catch(Exception e){

}

Message msg = new Message();
Bundle bundle = new Bundle();
bundle.putString("text", "handler text");
msg.setData(bundle);

MyHandlerActivity.this.myHandler.sendMessage(msg);
}


}

}