开启

            Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
            startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);

关闭

 
mBTAdapter = BluetoothAdapter.getDefaultAdapter(); 
mBTAdapter.disable(); 

获取已经配对的设备

mPairedDevices = mBTAdapter.getBondedDevices();
for (BluetoothDevice device : mPairedDevices)
               device.getName() + "\n" + device.getAddress();