学步园

在智能电视TV开发---直播视频客户端结构设计和实现中，我们设计出了简单的客户端，这里这个客户端与智能电视上面的TV服务端进行通信，实现手机控制电视来播放节目。

一、手机端UDP的client实现

  在智能电视TV开发---客户端和服务器通信中我是使用PC端来做客户端与智能电视TV通信的，现在需要把PC端的代码移植到手机端就可以了，这一步很容易。代码如下：

package com.jwzhangjie.smarttv_client.server.service;

import java.io.IOException;
import java.io.Serializable;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;

import android.os.AsyncTask;

public class UDPClient implements Serializable{

	private static final long serialVersionUID = 1L;
	private DatagramSocket udpSocket;
	private  DatagramPacket dataPacket;
	private static final int DEFAULT_PORT = 43701;
	private static final int MAX_DATA_PACKET_LENGTH = 40;
	private byte[] buffer = new byte[MAX_DATA_PACKET_LENGTH];
	private String scret = "jwzhangjie";//验证密钥
	private boolean connect = false;
	
	private static class SingleHolder{
		private static UDPClient instance = new UDPClient();
	}
	
	public static UDPClient getInstance(){
		return SingleHolder.instance;
	}
	
	/**
	 * 在串行化和反串行化中
	 * 阻止产生新的实例，总是返回当前对象
	 * @return
	 */
	private Object readResolve(){
		return SingleHolder.instance;
	}
	
	/**
	 * 建立通信连接
	 */
	public boolean startUDP(){
		new startBack().execute();
		 return connect;
	}
	
	private class startBack extends AsyncTask<Void, Void, Void>{
		@Override
		protected Void doInBackground(Void... params) {
			try {
			       udpSocket = new DatagramSocket(DEFAULT_PORT );
			       dataPacket = new DatagramPacket(buffer, MAX_DATA_PACKET_LENGTH);      
			       dataPacket.setPort( DEFAULT_PORT );
			       InetAddress broadcastAddr;
			       broadcastAddr = InetAddress.getByName("255.255.255.255");
			       dataPacket.setAddress(broadcastAddr);
			       connect = true;
			   } catch (Exception e) {
				   e.printStackTrace();
			   }
			 if (connect) {
				 showInfo("初始化成功");
			}else {
				showInfo("初始化失败");
			}
			return null;
		}
		
	}
	/**
	 * 发送数据
	 * @param data
	 */
	public void sendMSG(String params){
		new sendBack().execute(params);
	}
	
	/**
	 * 使用线程运行的目的是因为4.0之后不允许网络操作在主线程中
	 */
	private class sendBack extends AsyncTask<String, Void, Void>{
		@Override
		protected Void doInBackground(String... params) {
			if (connect) {
				showInfo(params[0]);
				byte[] data = params[0].getBytes();
				dataPacket.setData(data);
				dataPacket.setLength(data.length);
				try {
					udpSocket.send(dataPacket);
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return null;
		}
		
	}
	
	/**
	 * 关闭客户端广播
	 */
	public void closeUDP(){
		if (connect) {
			if (udpSocket != null && !udpSocket.isClosed() && udpSocket.isConnected()) {
				udpSocket.close();
				udpSocket = null;
				dataPacket = null;
			}
			showInfo("关闭客户端");
		}
	}
	
	public void showInfo(String params){
		System.out.println(params);
	}
}

上面的代码需要主要的地方就是Android系统功能是与权限挂钩，不同版本也是有差异的，就如上面的网络通信在4.0之后就不允许在主线程中运行。

二、手机客户端主界面代码

package com.jwzhangjie.smarttv_client;

import java.util.List;

import com.jwzhangjie.smarttv_client.adapter.LiveVideoAdapter;
import com.jwzhangjie.smarttv_client.model.LiveVideoModel;
import com.jwzhangjie.smarttv_client.server.service.UDPClient;
import com.jwzhangjie.smarttv_client.utils.DBUtils;

import android.os.AsyncTask;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.Window;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;

public class Smart_TV_Client extends Activity {

	private ListView listView;
	private LiveVideoAdapter adapter;
	private DBUtils dbUtils;
	private List<LiveVideoModel> listDatas;
	public static Smart_TV_Client instance;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		requestWindowFeature(Window.FEATURE_NO_TITLE);
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_smart__tv__client);
		instance = this;
		dbUtils = new DBUtils(this);
		initView();
		initListener();
		UDPClient.getInstance().startUDP();
		loadData();
	}
	
	@Override
	protected void onDestroy() {
		UDPClient.getInstance().closeUDP();
		super.onDestroy();
	}


	public void initView(){
		adapter = new LiveVideoAdapter(this);
		listView = (ListView)findViewById(R.id.listview);
		listView.setAdapter(adapter);
	}
	
	public void initListener(){
		listView.setOnItemClickListener(new OnItemClickListener() {
			@Override
			public void onItemClick(AdapterView<?> parent, View view,
					int position, long id) {
				LiveVideoModel video = listDatas.get(position);
				UDPClient.getInstance().sendMSG(video.getUrl());
			}
		});
	}
	
	public void loadData(){
		new loadData().execute();
	}
	
	private class loadData extends AsyncTask<Void, Void, Void>{
		@Override
		protected Void doInBackground(Void... params) {
			listDatas = dbUtils.getLiveVideoModels();
			return null;
		}

		@Override
		protected void onPostExecute(Void result) {
			adapter.updateListDatas(listDatas);
			super.onPostExecute(result);
		}
		
	}
	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.smart__tv__client, menu);
		return true;
	}
}