android编程4：多线程编程

本文博客链接:http://blog.csdn.net/jdh99,作者:jdh,转载请注明.

功能与编程3中一样，当按下键后，发送文本框中数据给PC。不同的是把发送数据的功能放在一个线程socket_send中。

环境：win7 + eclipse + ndk

代码：

主类test_socket.java

package test.soket;

//import com.test_button.R;

import java.io.DataOutputStream;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.Socket;
import java.net.SocketException;
import java.net.UnknownHostException;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class test_socket extends Activity {
	public static TextView show;
	public static Button press;
	public static boolean flag;
	
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        //开辟控件空间
        show = (TextView)findViewById(R.id.editText1);
        press = (Button)findViewById(R.id.button1);
        flag = false;
        soket_send thread = new soket_send();
        thread.init();
        thread.start();
	       
        press.setOnClickListener(new Button.OnClickListener()
        {
        	@Override
        	public void onClick(View v)
        	{
        		flag = true;
        	}
        });
    }
}

线程类socke_sendt.java:

package test.soket;

import java.io.DataOutputStream;  
import java.io.IOException;  
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.Socket;  
import java.net.SocketException;
import java.net.UnknownHostException;  
import java.util.LinkedList;  
  
import android.media.AudioFormat;  
import android.media.AudioRecord;  
import android.media.MediaRecorder;  
import android.util.Log;   

public class soket_send extends Thread
{ 
	private static final int MAX_DATA_PACKET_LENGTH = 40;
    private byte[] buffer = new byte[MAX_DATA_PACKET_LENGTH];
    private DatagramPacket dataPacket;
    private DatagramSocket udpSocket; 
    
    public void init()  
	{  
    	try
        {
        	udpSocket = new DatagramSocket(5554);
        }
        catch (SocketException e)
        {
        	// TODO Auto-generated catch block
        	e.printStackTrace();
        }
        dataPacket = new DatagramPacket(buffer, MAX_DATA_PACKET_LENGTH);
        String str = "hello,jdh";  //这是要传输的数据
		byte out [] = str.getBytes();  //把传输内容分解成字节
        dataPacket.setData(out);
        dataPacket.setLength(out.length);
        dataPacket.setPort(5554);
        
        try
        {
                
        	InetAddress broadcastAddr = InetAddress.getByName("192.168.0.248");
        	dataPacket.setAddress(broadcastAddr);
        	udpSocket.send(dataPacket);
        }
        catch (IOException e)
        {
        	// TODO Auto-generated catch block
        	e.printStackTrace();
        }	  
	}  
    
    public void run() 
    {  
    	while (true)
    	{
    		if (test_socket.flag)
    		{
		    	//获得输入框文本
				CharSequence str =test_socket.show.getText();
		        byte out[] = str.toString().getBytes();
		        dataPacket.setData(out);
		        dataPacket.setLength(out.length);
		        try
		        {
		                
		        	InetAddress broadcastAddr = InetAddress.getByName("192.168.0.248");
		        	dataPacket.setAddress(broadcastAddr);
		        	udpSocket.send(dataPacket);
		        }
		        catch (IOException e)
		        {
		        	// TODO Auto-generated catch block
		        	e.printStackTrace();
		        }
		        
		        test_socket.flag = false;
    		}
    	}
    }  
}

注意：程序中采用的线程间通信的方法是把需要共享的变量设置成public属性