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I'm trying to find all devices that are paired and are in range of my mobile device.

I'm testing with my laptop and my sony amp which are bluetooth enabled.

I can find my laptop, but my amp always returns "read failed, socket might closed or timeout, read ret: -1". My laptop is connected to my amp via bluetooth playing spotify - so maybe this is why my phone can't connect. However I still need to be able to detect whether this device is in range regardless of whether I can connect to it.

Here is some example code showing how I am trying to retrieve the devices. I got this solution from this SO answer https://stackoverflow.com/a/25647197/400320 

 Set<BluetoothDevice> bondedDevices = new HashSet<>(getBondedDevices());
    Set<BluetoothDevice> connectedDevices = new HashSet<>();
    for (BluetoothDevice device : bondedDevices) {
        BluetoothDevice actual = bluetoothAdapter.getRemoteDevice(device.getAddress());
        UUID SERIAL_UUID = actual.getUuids()[0].getUuid(); //if you don't know the UUID of the bluetooth device service, you can get it like this from android cache

        BluetoothSocket socket = null;

        try {
            socket = device.createRfcommSocketToServiceRecord(SERIAL_UUID);
        } catch (Exception e) {
            Log.e("", "Error creating socket");
        }

        try {
            socket.connect();
            connectedDevices.add(device);
            Log.e("", "Connected");
        } catch (IOException e) {
            Log.e("", e.getMessage());
            try {
                Log.e("", "trying fallback...");

                socket = (BluetoothSocket) actual.getClass().getMethod("createRfcommSocket", new Class[]{int.class}).invoke(actual, 1);
                socket.connect();
                connectedDevices.add(device);
                Log.e("", "Connected");
            } catch (Exception e2) {
                Log.e("", "Couldn't establish Bluetooth connection!");
            }
        } finally {
            if (socket != null) {
                try {
                    socket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
    return connectedDevices;
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serenskye
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  • It's likely that your amp doesn't offer serial communication over bluetooth. – 323go Sep 16 '15 at 13:54
  • What does that mean? My phone has also previously been paired with my amp as well as my laptop – serenskye Sep 16 '15 at 13:57
  • It's really out of the scope of comments, but Bluetooth offers different service profiles. Your amplifier is likely an audio-device, so it offers A2DP. If you're opening an rfcomm socket, it would look for an SPP profile, which your amp may or may not have. Thus, connection refused. – 323go Sep 16 '15 at 18:28
  • In that case, Is there an alternative way I can ascertain that it is in range? Feel free to answer as an answer rarther than a comment :) – serenskye Sep 17 '15 at 09:14

0 Answers0