class="aTitle" style="text-align: center">handler消息机制入门

 1 package com.example.handlerrumen;
 2 
 3 import android.app.Activity;
 4 import android.os.Bundle;
 5 import android.os.Handler;
 6 import android.os.Looper;
 7 import android.os.Message;
 8 import android.util.Log;
 9 import android.widget.TextView;
10 
11 public class MainActivity extends Activity {
12     private TextView tv_txt;
13     private Handler handler=new Handler(){
14         //处理消息（被主线程执行）
15         public void handleMessage(Message msg) {
16             String str=(String) msg.obj;
17             tv_txt.setText(str);
18             
19             //判断当前函数是否被主线程调用的方式
20 //            boolean result=Looper.getMainLooper()==Looper.myLooper();
21 //            Log.d("bh",result+"");
22         };
23     };
24     @Override
25     protected void onCreate(Bundle savedInstanceState) {
26         super.onCreate(savedInstanceState);
27         setContentView(R.layout.activity_main);
28         tv_txt=(TextView) findViewById(R.id.tv_txt);
29         //创建子线程，并启动
30         MyThread myTh=new MyThread();
31         myTh.start();
32     }
33     //自定义子线程
34     class MyThread extends Thread{
35         @Override
36         public void run() {
37             //伪代码来体现
38             try {
39                 Thread.sleep(6000);
40                 Log.d("bh","访问到网络了");
41                 String str="我是网络数据";
42                 //创建message对象
43                 Message msg=new Message();
44                 msg.obj=str;
45                 //发送一个消息
46                 handler.sendMessage(msg);
47             } catch (InterruptedException e) {
48                 e.printStackTrace();
49             }
50         }
51     }
52 }