蓝牙编程

 

蓝牙通讯;与LAN一样，通过MAC地址来识别远程设备，

通过蓝牙串口协议（SPP）建立端口后以输入输出方式通讯，与socket通讯类似。关键代码在于：将建立，连接好的socket传入线程中，利用新开启的线程发送接收数据。

 private static Context context;
 private BluetoothAdapter m_bluetoothadapter;
 private OutputStream outstream;
 private InputStream instream;
 private OnPortListener onportlistener;
 // 构造方法 
   public BluetoothChat(Context pContext) { 
      context = pContext; 
      message.what = 1; 
      onportlistener = (OnPortListener) pContext; 
 } 

public interface OnPortListener {
  public abstract void OnReceiveData(String p_Message); 
 }
 private Handler m_handler=new Handler(){
  @Override
  public void handleMessage(Message msg) {
   // TODO Auto-generated method stub
   super.handleMessage(msg);
   switch(msg.what)
   {
   case 1:
    Toast.makeText(context, "蓝牙设备未开启", Toast.LENGTH_LONG);
   }
  }
  
 };

 public class PortListenThread extends Thread{
  private BluetoothServerSocket serversocket;
  BluetoothSocket clientsocket=null;
  PortListenThread(BluetoothServerSocket socket)
  {
   serversocket=socket;
  }
  @Override
  public void run() {
   // TODO Auto-generated method stub
   super.run();
   try {
    //接受对方数据
    clientsocket=serversocket.accept();
    //获得输出流
    outstream =clientsocket.getOutputStream();
    //修改状态，改为连接状态
    m_state=m_stateConnected;
    while(m_state == m_stateConnected)
    {
     instream=clientsocket.getInputStream();
     RecviceData();
    }
   } catch (IOException e) {
    // TODO Auto-generated catch block
    if(!m_bluetoothadapter.isEnabled())
    {
     m_handler.sendMessage(msg);
    }
    e.printStackTrace();
   }
  }
  private void RecviceData()  {
   // TODO Auto-generated method stub
   //高效接受数据：
   byte[] bytes=new byte[8];//前8位为数据长度。
   try {
    instream.read(bytes);
    String lenstr=new String(bytes);
    int length=Integer.parseInt(lenstr);//长度
    byte[] bts =new byte[length];
    instream.read(bts);
    String msg=lenstr+ new String(bts);
   } catch (IOException e) {
    // TODO Auto-generated catch block
    Clone();//关闭socket ，重启
    e.printStackTrace();
   }//读取输入存在bytes

   //调用回调，在界面处理

  }
  private void Clone() {
   // TODO Auto-generated method stub
   serversocket.close();
   clientsocket.close();
   if(instream!=null)
   {
    instream.close();
   }
   if(outstream!=null)
   {
    outstream.close();
   }
  }
  private void SendData(String data)
  {//发送数据
   try {// 调用输出流向对方发送数据
    outstream.write(data.getBytes());
    outstream.flush();// 强制输出所有缓冲的数据 
   } catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }
  }
 }

private static final String S_NAME = "BluetoothChat"; 
    private static final UUID S_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");// UUID随机产生 

 public void CreatePortListen()
 {
  //获取本机的一个蓝牙设备
  m_bluetoothadapter =BluetoothAdapter.getDefaultAdapter();
  if(m_bluetoothadapter==null || m_bluetoothadapter.isEnabled())
  {
   //建立一个无线设备监听端口 类似于socket通讯。
   BluetoothServerSocket bluetoothst = null;
   try {
    bluetoothst = m_bluetoothadapter.listenUsingRfcommWithServiceRecord(S_NAME, S_UUID);
   } catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }
   //启动线程监听：
   PortListenThread thread=new PortListenThread(bluetoothst);
   thread.start();
  }
  else
  {
   m_handler.sendMessage(msg);
  }
 }

 注意  在最后，要XML开启 使用蓝牙权限。

上面OnPortListener 接口的使用目的在于可以让activity 实现这个接口，将数据传达到activity 显示。