{
        QLowEnergyCharacteristicData charData;
        charData.setUuid(QBluetoothUuid::CharacteristicType::ServiceChanged);
        charData.setProperties(QLowEnergyCharacteristic::Indicate);
        const QLowEnergyDescriptorData cpClientConfig(QBluetoothUuid::ClientCharacteristicConfiguration,
                                                      QByteArray(2, 0));
        charData.addDescriptor(cpClientConfig);

        serviceDataChanged.setType(QLowEnergyServiceData::ServiceTypePrimary);
        serviceDataChanged.setUuid(QBluetoothUuid::ServiceClassUuid::GenericAttribute);
        serviceDataChanged.addCharacteristic(charData);
    }

    //! [Start Advertising]
    leController = QLowEnergyController::createPeripheral();
    Q_ASSERT(leController);

    if(service_changed)
        serviceChanged = leController->addService(serviceDataChanged);