android开发之蓝牙配对连接的方法

最近在做蓝牙开锁的小项目，手机去连接单片机总是出现问题，和手机的连接也不稳定，看了不少蓝牙方面的文档，做了个关于蓝牙连接的小结。

在做android蓝牙串口连接的时候一般会使用

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BluetoothSocket tmp = null;
// Get a BluetoothSocket for a connection with the
// given BluetoothDevice
try {
tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) {
Log.e(TAG, "create() failed", e);
}

然后是tmp赋给BluetoothSocket,接着调用connect方法进行蓝牙设备的连接。

可是 BluetoothSocket 的connect方法本身就会报很多异常错误。

以下根据对蓝牙开发的一点研究可通过以下方法解决：

方法1.先进行蓝牙自动配对，配对成功，通过UUID获得BluetoothSocket,然后执行connect()方法。

方法2.通过UUID获得BluetoothSocket,然后先根据mDevice.getBondState()进行判断是否需要配对，最后执行connnect()方法。

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private class ConnectThread extends Thread {
    String macAddress = "";

    public ConnectThread(String mac) {
        macAddress = mac;
    }

    public void run() {
        connecting = true;
        connected = false;
        if(mBluetoothAdapter == null){
            mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
        }
        mBluetoothDevice = mBluetoothAdapter.getRemoteDevice(macAddress);
        mBluetoothAdapter.cancelDiscovery();
        try {
            socket = mBluetoothDevice.createRfcommSocketToServiceRecord(uuid);

        } catch (IOException e) {
            // TODO Auto-generated catch block
            //e.printStackTrace();
            Log.e(TAG, "Socket", e);
        }
        //adapter.cancelDiscovery();
        while (!connected && connetTime <= 10) {
            connectDevice();
        }
        // 重置ConnectThread
        //synchronized (BluetoothService.this) {
           //ConnectThread = null;
        //}
    }

    public void cancel() {
        try {
            socket.close();
            socket = null;
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            connecting = false;
        }
    }
}

接下来是调用的连接设备方法connectDevice():

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protected void connectDevice() {
        try {
            // 连接建立之前的先配对
            if (mBluetoothDevice.getBondState() == BluetoothDevice.BOND_NONE) {
                Method creMethod = BluetoothDevice.class
                        .getMethod("createBond");
                Log.e("TAG", "开始配对");
                creMethod.invoke(mBluetoothDevice);
            } else {
            }
        } catch (Exception e) {
            // TODO: handle exception
            //DisplayMessage("无法配对！");
            e.printStackTrace();
        }
        mBluetoothAdapter.cancelDiscovery();
        try {
            socket.connect();
            //DisplayMessage("连接成功!");
            //connetTime++;
            connected = true;
        } catch (IOException e) {
            // TODO: handle exception
            //DisplayMessage("连接失败！");
            connetTime++;
            connected = false;
            try {
                socket.close();
                socket = null;
            } catch (IOException e2) {
                // TODO: handle exception
                Log.e(TAG, "Cannot close connection when connection failed");
            }
        } finally {
            connecting = false;
        }
    }

方法3.利用反射通过端口获得BluetoothSocket,然后执行connect()方法。

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private class ConnectThread extends Thread {
    String macAddress = "";

    public ConnectThread(String mac) {
        macAddress = mac;
    }

    public void run() {
        connecting = true;
        connected = false;
        if(mBluetoothAdapter == null){
            mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
        }
        mBluetoothDevice = mBluetoothAdapter.getRemoteDevice(macAddress);
        mBluetoothAdapter.cancelDiscovery();
        initSocket();
        //adapter.cancelDiscovery();
        while (!connected && connetTime <= 10) {
            try {
                socket.connect();
                connected = true;
            } catch (IOException e1) {
                connetTime++;
                connected = false;
                // 关闭 socket
                try {
                    socket.close();
                    socket = null;
                } catch (IOException e2) {
                    //TODO: handle exception
                    Log.e(TAG, "Socket", e2);
                }
            } finally {
                connecting = false;
            }
            //connectDevice();
        }
        // 重置ConnectThread
        //synchronized (BluetoothService.this) {
           //ConnectThread = null;
        //}
    }

    public void cancel() {
        try {
            socket.close();
            socket = null;
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            connecting = false;
        }
    }
}

接下来是初始化并得到BluetoothSocket的方法

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/**
     * 取得BluetoothSocket
     */
    private void initSocket() {
        BluetoothSocket temp = null;
        try {
            Method m = mBluetoothDevice.getClass().getMethod(
                    "createRfcommSocket", new Class[] { int.class });
            temp = (BluetoothSocket) m.invoke(mBluetoothDevice, 1);//这里端口为1
        } catch (SecurityException e) {
            e.printStackTrace();
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
        } catch (IllegalArgumentException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        }
        socket = temp;
    }