android中的Handler

　　我的实例：

package com.wyl.wylhandler;



import android.os.Bundle;

import android.os.Handler;

import android.os.Message;

import android.support.v7.app.ActionBarActivity;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.TextView;



public class MainActivity extends ActionBarActivity {

	TextView tv;

	Button btn;

	Message msg;

	Handler handler;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        tv = (TextView)findViewById(R.id.textViewId); //获取TextView

        btn = (Button)findViewById(R.id.buttonId);	  //获取Button

        myOnclickListener l = new myOnclickListener();//实例化一个监听器l

        btn.setOnClickListener(l);					  //btn绑定上面获取的监听器l

        

    }



    class myOnclickListener implements OnClickListener{

    	@Override

    	public void onClick(View v) {

    		String c = "wyl";//设置断点用的

    		int len = c.length();//设置断点用的

    		System.out.println("len:"+len);

    		//1 .通过handler对象来获取message

    		myHandler myhandler = new myHandler();

    		msg = myhandler.obtainMessage();

    		String a = "zhang雅岚";//设置断点用的

    		msg.what = len;

    		msg.obj = a;

    		//handler sendMessage(msg)后，looper就自动从消息队列里取出msg(通过handleMessage方法),

    		myhandler.sendMessage(msg);	//handler把msg存入队列中

    		System.out.println("onClick所在线程："+Thread.currentThread().getName());

    	}	//调试发现，loop是在这一行的时候获取handler存入队列中的值msg

    }

    

    class myHandler extends Handler{

    	@Override

    	public void handleMessage(Message message) {

    		String name = "weiyongle";		//设置断点用的

    		int len2 = name.length();		//设置断点用的

    		System.out.println("len2:"+len2+","+"myHandler："+Thread.currentThread().getName());

    		Object obj = message.obj;		

    		System.out.println("myHandler里打印出来："+obj+"myHandler所在线程："+Thread.currentThread().getName());

    		

    	}

    }

    



}