BluetoothManager Sınıfı

openGattServer metodu
Şöyle yaparız.

BluetoothGattServerCallback mGattServerCallback =   new BluetoothGattServerCallback() {

  @Override
  public void onCharacteristicReadRequest(BluetoothDevice device, int requestId,
    int offset, BluetoothGattCharacteristic characteristic) {
    ...
  }
};

mGattServer = bluetoothManager.openGattServer(mContext, mGattServerCallback);