<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />

private BluetoothAdapter adapter = null;//用于获取蓝牙适配器
private BluetoothDevice mBtDevice = null;//用于获取蓝牙设备
private BluetoothSocket mBtSocket = null;//用于建立通信

adapter = BluetoothAdapter.getDefaultAdapter();

boolean enabled = adapter.enable();
if(!enabled){
        adapter.enable();
}

搜索设备：

adapter.startDiscovery();

private BroadcastReceiver blueRevever = new BroadcastReceiver(){

			@Override
			public void onReceive(Context context, Intent intent) {
				// TODO Auto-generated method stub
				String action = intent.getAction();
				if(action.equals(BluetoothDevice.ACTION_FOUND)){
					BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
					if(device.getBondState()!=BluetoothDevice.BOND_BONDED){
						//获取未配对的设备名称和MAC地址
						//依据搜索到的蓝牙设备的MAC地址，得到该设备
						mBtDevice = adapter.getRemoteDevice(device.getAddress());  
						//假设设备名称是指定的设备则给出提示
						if(device.getName().equals("HC-06")){
							Toast.makeText(MainActivity.this,device.getName(),Toast.LENGTH_LONG).show();
						}
					}
					else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {

						Toast.makeText(MainActivity.this,"检測完成",Toast.LENGTH_LONG).show();
					}
				}}};

 IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);

	    registerReceiver(blueRevever, filter);

	    filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);

	    registerReceiver(blueRevever, filter);

连接设备：

private class clientThread extends Thread{
  		public void run(){
  			try {
  				//取消搜索设备的动作。否则接下来的设备连接会失败
  				adapter.cancelDiscovery();
  				//依据device获取socket
  				mBtSocket = mBtDevice.createRfcommSocketToServiceRecord(UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"));
  				//连接socket
  				mBtSocket.connect();
  			} catch (IOException e) {
  				// TODO Auto-generated catch block
  				e.printStackTrace();
  				Toast.makeText(MainActivity.this,"连接失败！。。！
！
！
！！！",Toast.LENGTH_LONG).show();
  			}
  		}
  	}

//创建连接的进程
Thread mBtClientConnectThread = new clientThread();  
//开启进程
mBtClientConnectThread.start();  

发送信息：

public void sendMessageHandle(String msg)   
  	    {         
  	        if (mBtSocket == null)    
  	        {  
  	        	Toast.makeText(MainActivity.this,"没有连接！。",Toast.LENGTH_LONG).show();
  	                return;  
  	        }  
  	          
  	        try {  
  	            OutputStream os = mBtSocket.getOutputStream();   
  	            os.write(msg.getBytes()); //发送出去的值为：msg  
  	            Toast.makeText(MainActivity.this,"发送成功！
！
",Toast.LENGTH_LONG).show();
  	        } catch (IOException e) {  
  	            // TODO Auto-generated catch block  
  	            e.printStackTrace();  
  	            Toast.makeText(MainActivity.this,"发送失败！
！！
。！！
！！！
",Toast.LENGTH_LONG).show();
  	        }             
  	    }