template typename enum as default value

Silvia-V

use QVariant::Invalid as template default value

    template <typename T, typename V = QVariant::Invalid>
    T *registerExServiceStp2(const ServiceType &type, void (T::*func)(const V &) = nullptr) {
        Service *service = typeToService(type);
        if (!service)
            return nullptr;
        if (!service->token()) {
            T *token = new T(service);
            if (func)
                (token->*func)(service->extraInfo().value<V>());
            service->token(token);
            emit moduleStatusChanged(type);
        }
        return dynamic_cast<T *>(service->token());
    }

but get this

error: ‘Invalid’ in ‘class QVariant’ does not name a type
line: template <typename T, typename V = typename QVariant::Invalid>

how should i fix it

jeremy_k

QVariant::Invalid is a value for the type QVariant::Type. template <typename T, QVariant::Type V = QVariant::Invalid> is probably what you're looking for. The other uses of V should to be updated in the same manner.

mrjj

Hi
Maybe

template <typename T, typename V = QVariant() >
....

if the intent was to have V be an invalid QVariant pr default if not specified.

Silvia-V

@mrjj Thank you. It really worked out with this method