Android-解决在主线程之外的线程不能访问界面组件的问题

报的异常错误： android.view.ViewRootImpl$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.

 

解决方法：使用Handle来处理来自线程的消息。

 

package com.example.net_simplenet;



import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

import java.net.Socket;

import java.net.UnknownHostException;



import android.app.Activity;

import android.os.Bundle;

import android.os.Handler;

import android.os.Message;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.TextView;



public class MainActivity extends Activity {

    TextView show;

    Button btn;

    //处理线程消息的handler

    Handler handler;

    //消息类型

    final static int MSG_TYPE = 0x123;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        show = (TextView) findViewById(R.id.show);

        btn = (Button) findViewById(R.id.button1);

        handler = new Handler()

        {

            @Override

            public void handleMessage(Message msg) {

                // TODO Auto-generated method stub

                //super.handleMessage(msg);

                if (msg.what == MSG_TYPE) {

                    show.setText(msg.obj.toString());

                }

            }

        };

        btn.setOnClickListener(new OnClickListener() {

            

            @Override

            public void onClick(View v) {

                // TODO Auto-generated method stub

                new Thread()

                {

                    @Override

                    public void run() {

                        try {

                            Socket socket = new Socket("192.168.14.100", 30000);

                            BufferedReader br = new BufferedReader(

                                    new InputStreamReader(socket.getInputStream()));

                            String line = br.readLine();

                            Message msg = new Message();

                            msg.what = MSG_TYPE;

                            msg.obj = line;

                            handler.sendMessage(msg);

                            br.close();

                            socket.close();

                        } catch (UnknownHostException e) {

                            // TODO Auto-generated catch block

                            e.printStackTrace();

                        } catch (IOException e) {

                            // TODO Auto-generated catch block

                            e.printStackTrace();

                        }

                    };

                }.start();

            }

        });

        

    }

}