Android下如何通过蓝牙发送字符串消息？

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

BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

if (bluetoothAdapter == null || !bluetoothAdapter.isEnabled()) {
    Intent enableBluetoothIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
    startActivityForResult(enableBluetoothIntent, REQUEST_ENABLE_BLUETOOTH);
}

Set<BluetoothDevice> pairedDevices = bluetoothAdapter.getBondedDevices();
BluetoothDevice targetDevice = null;

for (BluetoothDevice device : pairedDevices) {
    if (device.getName().equals("目标设备名称")) {
        targetDevice = device;
        break;
    }
}

BluetoothSocket socket = targetDevice.createRfcommSocketToServiceRecord(MY_UUID);
socket.connect();

OutputStream outputStream = socket.getOutputStream();
String message = "要发送的消息";
outputStream.write(message.getBytes());

socket.close();