Android Bluetooth LE scan for UUID

Question

I tried the android sample app for BLE, but I can't get the desired output. Need to know how I can specifically scan for a UUID and get the message the device is transmitting.

For BLE transmitter I am using my macbook as transmitter using MacRadius to make it act as a beacon.

I just want to detect my mac's uuid and later fetch some info from it.

Need code example

Thanks

score -1 · Answer 1 · answered Nov 13 '14 at 19:34

Primary service UUIDs can be parsed from the scanRecord parameter passed to BluetoothAdapter.LeScanCallback#onLeScan() using the following snippet:

public static List<UUID> parseServiceUuids(final byte[] advertisedData)
    {
        List<UUID> uuids = new ArrayList<UUID>();

         if( advertisedData == null )  return uuids;

        int offset = 0;
        while(offset < (advertisedData.length - 2))
        {
            int len = advertisedData[offset++];
            if(len == 0)
                break;

            int type = advertisedData[offset++];
            switch(type)
            {
                case 0x02: // Partial list of 16-bit UUIDs
                case 0x03: // Complete list of 16-bit UUIDs
                    while(len > 1)
                    {
                        int uuid16 = advertisedData[offset++];
                        uuid16 += (advertisedData[offset++] << 8);
                        len -= 2;
                        uuids.add(UUID.fromString(String.format("%08x-0000-1000-8000-00805f9b34fb", uuid16)));
                    }
                    break;
                case 0x06:// Partial list of 128-bit UUIDs
                case 0x07:// Complete list of 128-bit UUIDs
                      // Loop through the advertised 128-bit UUID's.
                    while(len >= 16)
                    {
                        try
                        {
                            // Wrap the advertised bits and order them.
                            ByteBuffer buffer = ByteBuffer.wrap(advertisedData, offset++, 16).order(ByteOrder.LITTLE_ENDIAN);
                            long mostSignificantBit = buffer.getLong();
                            long leastSignificantBit = buffer.getLong();
                            uuids.add(new UUID(leastSignificantBit, mostSignificantBit));
                        }
                        catch(IndexOutOfBoundsException e)
                        {
                            // Defensive programming.
                            Log.e(TAG, e.toString());
                            continue;
                        }
                        finally
                        {
                            // Move the offset to read the next uuid.
                            offset += 15;
                            len -= 16;
                        }
                    }
                    break;
                default:
                    offset += (len - 1);
                    break;
            }
        }

        return uuids;
    }

You'll then have to parse scanRecord yourself further to get more information from it.

Android Bluetooth LE scan for UUID

1 Answers1