Connect to Android Bluetooth socket

Question

Hi I am trying to create an Android app which will connect to a Blue SMiRF Bluetooth dongle which I want to send data to. I have read over the developer pages and looked at multiple different examples however I am currently having trouble creating a connection to the socket. The Bluetooth portion of the code is pretty much from an example that I was able to find. When trying to connect to the Bluetooth dongle the app gets a force close because there is some error I am not handling correctly. However I have also tried to use the app just to connect to another PC and the connection wont get established correctly for some reason even though I am already paired with the device through the Bluetooth settings before I even run the app. I have posted some of the more important code below for where I think my issue may be. Any help will be very appreciated, please let me know if I should post any additional code.

protected void connect(BluetoothDevice device) {
    //BluetoothSocket socket = null;
    try {
        //Create a Socket connection: need the server's UUID number of registered

        socket = device.createRfcommSocketToServiceRecord(UUID.fromString("a60f35f0-b93a-11de-8a39-08002009c666"));



        socket.connect();
        Log.d("EF-BTBee", ">>Client connectted");

        InputStream inputStream = socket.getInputStream();                                                      
        OutputStream outputStream = socket.getOutputStream();
        outputStream.write(new byte[] { (byte) 0xa0, 0, 7, 16, 0, 4, 0 });


        new Thread() {
            public void run() {
                    while(true)
                    {   
                    try {
                        Log.d("EF-BTBee", ">>Send data thread!");
                        OutputStream outputStream = socket.getOutputStream();
                        outputStream.write(new byte[] { (byte) 0xa2, 0, 7, 16, 0, 4, 0 });
                    } catch (IOException e) {
                        Log.e("EF-BTBee", "", e);
                    }
                    }
            };
        }.start();

    } catch (IOException e) {
        Log.e("EF-BTBee", "", e);
    } finally {
        if (socket != null) {
            try {
                Log.d("EF-BTBee", ">>Client Close");
                socket.close(); 
                finish();
                return ;
            } catch (IOException e) {
                Log.e("EF-BTBee", "", e);
            }
        }
    }
}`

I have also tried using

Method m = device.getClass().getMethod("createRfcommSocket", new Class[] {int.class});

        socket = (BluetoothSocket) m.invoke(device, 1);

instead of just the "socket =" line from above and still had no success.

Answer 1

if the device is already paired , then you can use

if(device.getBondState()==device.BOND_BONDED){
    Log.d(TAG,device.getName());
    //BluetoothSocket mSocket=null;
    try {
        mSocket = device.createInsecureRfcommSocketToServiceRecord(MY_UUID);
    } catch (IOException e1) {
        // TODO Auto-generated catch block
        Log.d(TAG,"socket not created");
        e1.printStackTrace();
    }
    try{
        mSocket.connect();
    }
    catch(IOException e){
        try {
            mSocket.close();
            Log.d(TAG,"Cannot connect");
        } catch (IOException e1) {
            Log.d(TAG,"Socket not closed");
            e1.printStackTrace();
        }
    }

for the MY_UUID use

private static final UUID MY_UUID = UUID.fromString("0000110E-0000-1000-8000-00805F9B34FB");