Android 蓝牙通信

蓝牙工具类

/**
 * @anthor GrainRain
 * @funcation 蓝牙工具类 提供回调接口和发送方法
 * @date 2019/10/25
 */
public class BluetoothUtil {

    private static BluetoothUtil bluetoothUtil;

    //这条是蓝牙串口通用的UUID，不要更改
    private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");

    //device var
    private BluetoothAdapter mBluetoothAdapter = null;
    private static BluetoothSocket btSocket = null;
    private static OutputStream outStream = null;
    private InputStream inStream = null;

    private ReceiveThread rThread=null;  //数据接收线程
    private MyHandler handler;

    //连接状态
    private static String statusLabel = "";

    private OnConnectListener onConnectListener;

    //初始化对象
    public static BluetoothUtil get() {
        if(bluetoothUtil == null) {
            bluetoothUtil = new BluetoothUtil();
        }
        return bluetoothUtil;
    }

    public BluetoothUtil() {
    }

    public void initBluetooth() {
        //得到一个蓝牙适配器
        mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
        if(mBluetoothAdapter == null) {
            Log.e("Bluetooth", "你的手机不支持蓝牙");
            return;
        }
    }

    //创建方法
    public void getMsg(String mac, OnConnectListener listener) {

        initBluetooth();
        handler = new MyHandler();


        //判断蓝牙是否打开
        if(!mBluetoothAdapter.isEnabled()) {
            mBluetoothAdapter.enable();
        }

        //自动配对
        //mBluetoothAdapter.startDiscovery();

        //创建连接
        //mac 要连接的目标蓝牙设备MAC地址
        new ConnectTask().execute(mac);

        setOnConnectListener(listener);
        listener.onConnectSuccess(null);
        listener.onConnectFailed(null);
    }

    //连接蓝牙设备的异步任务
    class ConnectTask extends AsyncTask<String,String,String> {

        @Override
        protected String doInBackground(String... params) {
            // TODO Auto-generated method stub
            BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(params[0]);
            try {
                btSocket = device.createRfcommSocketToServiceRecord(MY_UUID);
                btSocket.connect();
                Log.e("error", "ON RESUME: BT connection established, data transfer link open.");
            } catch (IOException e) {
                try {

                    //将异常信息传递给回调接口
                    if(getOnConnectListener() != null) {
                        getOnConnectListener().onConnectFailed(e);
                    }
                    btSocket.close();
                    return "Socket 创建失败";
                } catch (IOException e2) {

                    //将异常信息传递给回调接口
                    if(getOnConnectListener() != null) {
                        getOnConnectListener().onConnectFailed(e2);
                    }
                    Log .e("error","ON RESUME: Unable to close socket during connection failure", e2);
                    return "Socket 关闭失败";
                }
            }
            //取消搜索
            mBluetoothAdapter.cancelDiscovery();
            try {
                outStream = btSocket.getOutputStream();
            } catch (IOException e) {

                //将异常信息传递给回调接口
                if(getOnConnectListener() != null) {
                    getOnConnectListener().onConnectFailed(e);
                }
                Log.e("error", "ON RESUME: Output stream creation failed.", e);
                return "Socket 流创建失败";
            }
            return "蓝牙连接正常,Socket 创建成功";
        }

        @Override    //这个方法是在主线程中运行的，所以可以更新界面
        protected void onPostExecute(String result) {
            // TODO Auto-generated method stub
            //连接成功则启动监听
            rThread = new ReceiveThread();
            rThread.start();
            statusLabel = result;
            Log.e("Bluetooth", "连接状态:" + result);

            super.onPostExecute(result);
        }
    }

    //从蓝牙接收信息的线程
    class ReceiveThread extends Thread {

        String buffer="";

        @Override
        public void run() {
            while(btSocket != null ) {

                //定义一个存储空间buff
                byte[] buff = new byte[1024];
                try {
                    inStream = btSocket.getInputStream();
                    System.out.println("waitting for instream");

                    if(inStream != null) {
                        inStream.read(buff); //读取数据存储在buff数组中
                    }
                    processBuffer(buff,1024);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

        public void processBuffer(byte[] buff,int size) {

            int length = 0;
            for(int i = 0; i < size; i++) {
                if(buff[i] > '\0') {
                    length++;
                } else {
                    break;
                }
            }

            //newbuff字节数组，用于存放真正接收到的数据
            byte[] newbuff = new byte[length];
            int[] receiveData = new int[length];

            for(int j = 0; j < length; j++) {
                newbuff[j] = buff[j];
                receiveData[j] = buff[j] & 0xff;
            }

            Log.w("收到数据: ", Arrays.toString(receiveData));
            //回调
            if(getOnConnectListener() != null) {
                getOnConnectListener().onConnectSuccess(receiveData);
            }

            Message msg= Message.obtain();
            msg.what=1;
            handler.sendMessage(msg);  //发送消息:系统会自动调用handleMessage( )方法来处理消息
        }
    }

    //发送数据到蓝牙设备的异步任务
    static class SendInfoTask extends AsyncTask<String,String,String> {

        @Override
        protected void onPostExecute(String result) {
            // TODO Auto-generated method stub
            super.onPostExecute(result);

            statusLabel = result;
            Log.e("Bluetooth", "连接状态:" + result);
        }

        @Override
        protected String doInBackground(String... arg0) {

            // TODO Auto-generated method stub
            if(btSocket == null) {
                return "还没有创建连接";
            }

            if(arg0[0].length()>0) {
                //不是空白串
                //String target=arg0[0];
                byte[] msgBuffer = arg0[0].getBytes();
                try {
                    if(outStream != null) {
                        //  将msgBuffer中的数据写到outStream对象中
                        outStream.write(msgBuffer);
                    }
                } catch (IOException e) {
                    Log.e("error", "ON RESUME: Exception during write.", e);
                    return "发送失败";
                }
            }
            return "发送成功";
        }
    }

    //更新界面的Handler类
    class MyHandler extends Handler {
        @Override
        public void handleMessage(Message msg) {
            switch(msg.what){
                case 1:
                    //显示接收的信息
//                    etReceived.setText(ReceiveData);
                    break;
            }
        }
    }

    //回调接口
    public interface OnConnectListener{
        //连接成功
        void onConnectSuccess(int[] msg);
        //连接异常信息
        void onConnectFailed(Exception e);
    }

    public OnConnectListener getOnConnectListener() {
        return onConnectListener;
    }

    public void setOnConnectListener(OnConnectListener onConnectListener) {
        this.onConnectListener = onConnectListener;
    }

}

使用

BluetoothUtil.get().getMsg("20:19:01:26:05:87", new BluetoothUtil.OnConnectListener() {
    @Override
    public void onConnectSuccess(int[] msg) {

    }

    @Override
    public void onConnectFailed(Exception e) {
        
    }
});