蓝牙串口app程序源码

### 回答1：
蓝牙串口APP程序源码是一种用于在移动设备上实现蓝牙串口通信的程序代码。以下是一个简单的示例源码：

import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.UUID;

public class BluetoothSerialActivity extends AppCompatActivity {
    private BluetoothAdapter mBluetoothAdapter;
    private BluetoothDevice mBluetoothDevice;
    private BluetoothSocket mBluetoothSocket;

    private TextView mTextView;
    private Button mButton;

    private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");

    private static final int MSG_READ = 0;
    private static final int MSG_WRITE = 1;
    private static final int MSG_TOAST = 2;

    private ConnectedThread mConnectedThread;

    private Handler mHandler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
                case MSG_READ:
                    byte[] buffer = (byte[]) msg.obj;
                    String receivedData = new String(buffer);
                    mTextView.setText(receivedData);
                    break;

                case MSG_WRITE:
                    byte[] writeBuffer = (byte[]) msg.obj;
                    String sentData = new String(writeBuffer);
                    mTextView.setText(sentData);
                    break;

                case MSG_TOAST:
                    Toast.makeText(getApplicationContext(), msg.getData().getString("toast"), Toast.LENGTH_SHORT).show();
                    break;
            }
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mTextView = findViewById(R.id.text_view);
        mButton = findViewById(R.id.button);

        mButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (mConnectedThread != null) {
                    mConnectedThread.write("Hello from BluetoothSerialApp".getBytes());
                }
            }
        });

        mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
        mBluetoothDevice = mBluetoothAdapter.getRemoteDevice("Bluetooth Device Address");

        ConnectThread connectThread = new ConnectThread(mBluetoothDevice);
        connectThread.start();
    }

    private void manageConnectedSocket(BluetoothSocket socket) {
        mConnectedThread = new ConnectedThread(socket);
        mConnectedThread.start();
    }

    private class ConnectThread extends Thread {
        private final BluetoothSocket mmSocket;

        public ConnectThread(BluetoothDevice device) {
            BluetoothSocket socket = null;

            try {
                socket = device.createRfcommSocketToServiceRecord(MY_UUID);
            } catch (IOException e) {
                e.printStackTrace();
            }
            mmSocket = socket;
        }

        public void run() {
            mBluetoothAdapter.cancelDiscovery();

            try {
                mmSocket.connect();
            } catch (IOException connectException) {
                connectException.printStackTrace();
                try {
                    mmSocket.close();
                } catch (IOException closeException) {
                    closeException.printStackTrace();
                }
                return;
            }

            manageConnectedSocket(mmSocket);
        }
    }

    private class ConnectedThread extends Thread {
        private final BluetoothSocket mmSocket;
        private final InputStream mmInStream;
        private final OutputStream mmOutStream;

        public ConnectedThread(BluetoothSocket socket) {
            mmSocket = socket;
            InputStream tmpIn = null;
            OutputStream tmpOut = null;

            try {
                tmpIn = mmSocket.getInputStream();
                tmpOut = mmSocket.getOutputStream();
            } catch (IOException e) {
                e.printStackTrace();
            }

            mmInStream = tmpIn;
            mmOutStream = tmpOut;
        }

        public void run() {
            byte[] buffer = new byte[1024];
            int bytes;

            while (true) {
                try {
                    bytes = mmInStream.read(buffer);
                    mHandler.obtainMessage(MSG_READ, bytes, -1, buffer).sendToTarget();
                } catch (IOException e) {
                    e.printStackTrace();
                    break;
                }
            }
        }

        public void write(byte[] buffer) {
            try {
                mmOutStream.write(buffer);
                mHandler.obtainMessage(MSG_WRITE, -1, -1, buffer).sendToTarget();
            } catch (IOException e) {
                e.printStackTrace();
                mHandler.obtainMessage(MSG_TOAST, "Failed to send data").sendToTarget();
            }
        }
    }
}

这段代码实现了一个简单的蓝牙串口通信APP。首先通过BluetoothAdapter获取BluetoothDevice对象，并使用蓝牙设备地址创建BluetoothSocket。然后创建ConnectThread在后台连接蓝牙设备，并在连接成功后创建ConnectedThread进行数据的读写。当点击按钮时，会将字符串发送给蓝牙设备，并在接收到数据时更新界面上的TextView。

### 回答2：
蓝牙串口app程序源码是一种用于通过蓝牙通信与串口设备进行数据传输的应用程序源代码。下面是一个简单的蓝牙串口app程序源码示例：

import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.os.Handler;
import android.os.Message;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.UUID;

public class BluetoothSerialService {
    private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
    private final BluetoothAdapter mAdapter;
    private final Handler mHandler;
    private ConnectThread mConnectThread;
    private ConnectedThread mConnectedThread;
    private int mState;

    private static final int STATE_NONE = 0; // 无连接
    private static final int STATE_CONNECTING = 1; // 连接中
    private static final int STATE_CONNECTED = 2; // 连接成功

    public BluetoothSerialService(Handler handler) {
        mAdapter = BluetoothAdapter.getDefaultAdapter();
        mHandler = handler;
        mState = STATE_NONE;
    }

    private synchronized void setState(int state) {
        mState = state;
        mHandler.obtainMessage(MainActivity.MESSAGE_STATE_CHANGE, state, -1).sendToTarget();
    }

    public synchronized int getState() {
        return mState;
    }

    public synchronized void connect(BluetoothDevice 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) {
        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);
        mHandler.sendMessage(msg);

        setState(STATE_CONNECTED);
    }

    public synchronized void stop() {
        if (mConnectThread != null) {
            mConnectThread.cancel();
            mConnectThread = null;
        }

        if (mConnectedThread != null) {
            mConnectedThread.cancel();
            mConnectedThread = null;
        }

        setState(STATE_NONE);
    }

    public void write(byte[] out) {
        ConnectedThread r;
        synchronized (this) {
            if (mState != STATE_CONNECTED) return;
            r = mConnectedThread;
        }
        r.write(out);
    }

    private void connectionFailed() {
        setState(STATE_NONE);
        Message msg = mHandler.obtainMessage(MainActivity.MESSAGE_TOAST);
        mHandler.sendMessage(msg);
    }

    private void connectionLost() {
        setState(STATE_NONE);
        Message msg = mHandler.obtainMessage(MainActivity.MESSAGE_TOAST);
        mHandler.sendMessage(msg);
    }

    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) {
                e.printStackTrace();
            }

            mmSocket = tmp;
        }

        public void run() {
            mAdapter.cancelDiscovery();

            try {
                mmSocket.connect();
            } catch (IOException connectException) {
                try {
                    mmSocket.close();
                } catch (IOException closeException) {
                    closeException.printStackTrace();
                }
                connectionFailed();
                return;
            }

            synchronized (BluetoothSerialService.this) {
                mConnectThread = null;
            }

            connected(mmSocket, mmDevice);
        }

        public void cancel() {
            try {
                mmSocket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    private class ConnectedThread extends Thread {
        private final BluetoothSocket mmSocket;
        private final InputStream mmInStream;
        private final OutputStream mmOutStream;
        private byte[] mmBuffer;

        public ConnectedThread(BluetoothSocket socket) {
            mmSocket = socket;
            InputStream tmpIn = null;
            OutputStream tmpOut = null;

            try {
                tmpIn = socket.getInputStream();
                tmpOut = socket.getOutputStream();
            } catch (IOException e) {
                e.printStackTrace();
            }

            mmInStream = tmpIn;
            mmOutStream = tmpOut;
        }

        public void run() {
            mmBuffer = new byte[1024];
            int numBytes;

            while (true) {
                try {
                    numBytes = mmInStream.read(mmBuffer);

                    byte[] readBuffer = new byte[numBytes];
                    System.arraycopy(mmBuffer, 0, readBuffer, 0, numBytes);

                    mHandler.obtainMessage(MainActivity.MESSAGE_READ, numBytes, -1, readBuffer).sendToTarget();
                } catch (IOException e) {
                    e.printStackTrace();
                    connectionLost();
                    break;
                }
            }
        }

        public void write(byte[] buffer) {
            try {
                mmOutStream.write(buffer);
                mHandler.obtainMessage(MainActivity.MESSAGE_WRITE, -1, -1, buffer).sendToTarget();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

        public void cancel() {
            try {
                mmSocket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

以上是一个简单的蓝牙串口app程序的示例代码，可以利用该代码实现与串口设备之间的数据传输。其中，主要包括`BluetoothSerialService`类用于实现蓝牙连接和数据传输的相关方法，`ConnectThread`类用于管理蓝牙连接，`ConnectedThread`类用于管理蓝牙数据的读写。此外，代码还包括一些状态常量和相应的处理方式。请注意，这只是一个简单的示例代码，实际应用中还需根据具体需求进行相应的修改和扩展。