4APP蓝牙通讯协议 格式：10Hz, 以ASCII字符串发送，英文逗号分隔，\r\n结束。 表5数据通讯协议 序号 数据定义 数据类型 备注 1 帧序号 unsigned int 每一帧数据+1，单独计数 2 系统状态 unsigned char 分别为 0 1 2 3 4 5 10，见表2 3 寻北进度 unsigned char 1~100 4 航向角 float 0~360° 5 俯仰角 float -90°~90° 6 横滚角 float -180°~180° 7 实时更新数据 float 帧序号进行除以10取余计算，见表3以里面的要求在andriod studio中写一个类

以下是在Android Studio中编写的一个类，用于发送和接收4APP蓝牙通讯协议格式的数据： ``` import android.bluetooth.BluetoothAdapter; import android.bluetooth.BluetoothDevice; import android.bluetooth.BluetoothSocket; import android.os.Handler; import android.os.Message; import android.util.Log; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.util.UUID; public class BluetoothConnectionService { private static final String TAG = "BluetoothConnectionServ"; private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"); private final BluetoothAdapter mBluetoothAdapter; private ConnectThread mConnectThread; private ConnectedThread mConnectedThread; private Handler mHandler; private int mState; private static final int STATE_NONE = 0; private static final int STATE_CONNECTING = 1; private static final int STATE_CONNECTED = 2; public BluetoothConnectionService(Handler handler) { mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter(); mState = STATE_NONE; mHandler = handler; } private synchronized void setState(int state) { Log.d(TAG, "setState() " + mState + " -> " + state); mState = state; mHandler.obtainMessage(MainActivity.MESSAGE_STATE_CHANGE, state, -1).sendToTarget(); } public synchronized int getState() { return mState; } public synchronized void connect(BluetoothDevice device) { Log.d(TAG, "connect to: " + device); if (mState == STATE_CONNECTING) { if (mConnectThread != null) { mConnectThread.cancel(); mConnectThread = null; } } if (mConnectedThread != null) { mConnectedThread.cancel(); mConnectedThread = null; } mConnectThread = new ConnectThread(device); mConnectThread.start(); setState(STATE_CONNECTING); } public synchronized void connected(BluetoothSocket socket, BluetoothDevice device) { Log.d(TAG, "connected"); if (mConnectThread != null) { mConnectThread.cancel(); mConnectThread = null; } if (mConnectedThread != null) { mConnectedThread.cancel(); mConnectedThread = null; } mConnectedThread = new ConnectedThread(socket); mConnectedThread.start(); Message msg = mHandler.obtainMessage(MainActivity.MESSAGE_DEVICE_NAME); msg.obj = device.getName(); mHandler.sendMessage(msg); setState(STATE_CONNECTED); } public synchronized void stop() { Log.d(TAG, "stop"); if (mConnectThread != null) { mConnectThread.cancel(); mConnectThread = null; } if (mConnectedThread != null) { mConnectedThread.cancel(); mConnectedThread = null; } setState(STATE_NONE); } public void write(String message) { ConnectedThread r; synchronized (this) { if (mState != STATE_CONNECTED) return; r = mConnectedThread; } byte[] msgBuffer = (message + "\r\n").getBytes(); r.write(msgBuffer); } private void connectionFailed() { Message msg = mHandler.obtainMessage(MainActivity.MESSAGE_TOAST); msg.obj = "Unable to connect device"; mHandler.sendMessage(msg); BluetoothConnectionService.this.start(); } private void connectionLost() { Message msg = mHandler.obtainMessage(MainActivity.MESSAGE_TOAST); msg.obj = "Device connection was lost"; mHandler.sendMessage(msg); BluetoothConnectionService.this.start(); } private class ConnectThread extends Thread { private final BluetoothSocket mmSocket; private final BluetoothDevice mmDevice; public ConnectThread(BluetoothDevice device) { mmDevice = device; BluetoothSocket tmp = null; try { tmp = device.createRfcommSocketToServiceRecord(MY_UUID); } catch (IOException e) { Log.e(TAG, "create() failed", e); } mmSocket = tmp; } public void run() { Log.i(TAG, "BEGIN mConnectThread"); setName("ConnectThread"); mBluetoothAdapter.cancelDiscovery(); try { mmSocket.connect(); } catch (IOException e) { connectionFailed(); try { mmSocket.close(); } catch (IOException e2) { Log.e(TAG, "unable to close() socket during connection failure", e2); } BluetoothConnectionService.this.start(); return; } synchronized (BluetoothConnectionService.this) { mConnectThread = null; } connected(mmSocket, mmDevice); } public void cancel() { try { mmSocket.close(); } catch (IOException e) { Log.e(TAG, "close() of connect socket failed", e); } } } private class ConnectedThread extends Thread { private final BluetoothSocket mmSocket; private final InputStream mmInStream; private final OutputStream mmOutStream; public ConnectedThread(BluetoothSocket socket) { Log.d(TAG, "create ConnectedThread"); mmSocket = socket; InputStream tmpIn = null; OutputStream tmpOut = null; try { tmpIn = socket.getInputStream(); tmpOut = socket.getOutputStream(); } catch (IOException e) { Log.e(TAG, "temp sockets not created", e); } mmInStream = tmpIn; mmOutStream = tmpOut; } public void run() { Log.i(TAG, "BEGIN mConnectedThread"); byte[] buffer = new byte[1024]; int bytes; while (true) { try { bytes = mmInStream.read(buffer); String readMessage = new String(buffer, 0, bytes); mHandler.obtainMessage(MainActivity.MESSAGE_READ, bytes, -1, readMessage).sendToTarget(); } catch (IOException e) { Log.e(TAG, "disconnected", e); connectionLost(); break; } } } public void write(byte[] buffer) { try { mmOutStream.write(buffer); mHandler.obtainMessage(MainActivity.MESSAGE_WRITE, -1, -1, buffer).sendToTarget(); } catch (IOException e) { Log.e(TAG, "Exception during write", e); } } public void cancel() { try { mmSocket.close(); } catch (IOException e) { Log.e(TAG, "close() of connect socket failed", e); } } } } ``` 这个类中包含了一个ConnectThread和一个ConnectedThread。ConnectThread用于在蓝牙设备上建立连接，而ConnectedThread用于处理连接后的输入和输出流。根据4APP蓝牙通讯协议的格式，我们可以在ConnectedThread的write()方法中将要发送的字符串转换为字节数组，然后将它们写入到输出流中。接收到的数据可以在ConnectedThread的run()方法中使用mmInStream读取，并将读取的字节转换为字符串后发送到主线程中进行处理。