Android主线程给多个线程发送消息

package com.boao; import java.util.ArrayList; import java.util.List; import android.app.Activity; import android.os.Bundle; import android.os.Handler; import android.os.Looper; import android.os.Message; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.TextView; public class MyHandlerActivity extends Activity { /** Called when the activity is first created. */ // 主线程给子线程发送消息 Button button3; TextView textView; // 主线程 MainActivityHandler mainHandler; // 其它线程 List<MyThreadHandler> list = new ArrayList<MyHandlerActivity.MyThreadHandler>(); @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); button3 = (Button) findViewById(R.id.button3); textView = (TextView) findViewById(R.id.text); button3.setOnClickListener(clickListener); for (int i = 0; i < 10; i++) { MyThread thread = new MyThread(); thread.start(); } } OnClickListener clickListener = new OnClickListener() { @Override public void onClick(View v) { switch (v.getId()) { // 主线程给子线程发送消息 case R.id.button3: // 在主线程中获取子线程的message对象然后再发送 for (int i = 0; i < list.size(); i++) { MyThreadHandler myThreadHandler = list.get(i); Message msg = myThreadHandler.obtainMessage(1, "这是主线程发送的消息" + myThreadHandler.toString()); // msg.obj="这是主线程发送的消息"; myThreadHandler.sendMessage(msg); } break; default: break; } } }; class MainActivityHandler extends Handler { public MainActivityHandler(Looper looper) { super(looper); } @Override public void handleMessage(Message msg) { super.handleMessage(msg); textView.setText("我是主线程，这是收到的消息：" + msg.obj + msg.getWhen()); } } // ////////////////////////////////////////////////////////////////////////// // 以下是其他线程类和他的handler类 class MyThread extends Thread { @Override public void run() { super.run(); // 创建该线程的Looper对象，用于接收消息 Looper.prepare(); // 线程的looper创建的handler表示消息接收者是子线程 MyThreadHandler myThreadHandler = new MyThreadHandler( Looper.myLooper()); list.add(myThreadHandler); // 循环从MessageQueue中取消息。 Looper.loop(); } } class MyThreadHandler extends Handler { public MyThreadHandler(Looper looper) { super(looper); } @Override public void handleMessage(Message msg) { super.handleMessage(msg); // textView.setText("我是子线程，这是收到的消息：" + msg.obj);这里直接操作UI线程的内容是不行的会出错 mainHandler = new MainActivityHandler(Looper.getMainLooper()); Message message = new Message(); message.obj = "子线程收到消息.收到的消息内容是:" + msg.obj; mainHandler.sendMessage(message); } } }