Android Handler

package com.example.myapp7;

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.os.Message;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
/**
* UI线程发送数据，子线程接收数据。
* @author shaobn
* @date 2015-9-15
* @packege com.example.myapp7MyApp7
*/
public class MainActivity extends ActionBarActivity {
private Button button;
private Handler handler;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button = (Button) this.findViewById(R.id.button1);
button.setOnClickListener(new View.OnClickListener() {

@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
Message message = handler.obtainMessage();
message.what = 8;
handler.sendMessage(message);
}
});
MyThread myThread = new MyThread();
Thread thread = new Thread(myThread);
thread.start();
}
class MyThread implements Runnable{
@Override
public void run() {
// TODO Auto-generated method stub
Looper.prepare();
handler = new Handler(){
@Override
public void handleMessage(Message msg) {
// TODO Auto-generated method stub
Log.i("msg","--->>>"+String.valueOf(msg.what));
}
};
Looper.loop();
}

}
}