Emitting enum class in namespace not working

Palli

Code: https://github.com/Drllap/EmitEnumFromNamspaceTest

Looks like I was wrong about this working with structs:
MyEnum and MyStruct are metatype declared with:

namespace MyNamespace {
    Q_DECLARE_METATYPE(MyEnum)
    Q_DECLARE_METATYPE(MyStruct)
}

and are successfully sent between threads but MyEnum2, MyStruct2

Q_DECLARE_METATYPE(MyNamespace::MyEnum2)
Q_DECLARE_METATYPE(MyNamespace::MyStruct2)

are not sent between threads.

Then there is another problem, this:

namespace MyNamespace {
    Q_DECLARE_METATYPE(MyEnum)
    Q_DECLARE_METATYPE(MyStruct)
}

doesn't compile on Ubuntu18 with GCC

Christian Ehrlicher

@Palli said in Emitting enum class in namespace not working:

are not sent between threads.

They are, please recheck.

doesn't compile on Ubuntu18 with GCC

Because you use the macro wrong:

If MyStruct is in a namespace, the Q_DECLARE_METATYPE() macro has to be outside the namespace.

This works as expected (and shown in the documentation)


Q_DECLARE_METATYPE(MyNamespace::MyEnum)
Q_DECLARE_METATYPE(MyNamespace::MyEnum2)
Q_DECLARE_METATYPE(MyNamespace::MyStruct)
Q_DECLARE_METATYPE(MyNamespace::MyStruct2)

void MetaRegister::RegisterAllOfTheThings()
{
    qDebug() << "Registering meta type: " << qRegisterMetaType<MyNamespace::MyEnum>();
    qDebug() << "Registering meta type: " << qRegisterMetaType<MyNamespace::MyEnum2>();
    qDebug() << "Registering meta type: " << qRegisterMetaType<MyNamespace::MyStruct>();
    qDebug() << "Registering meta type: " << qRegisterMetaType<MyNamespace::MyStruct2>();
}

Palli

@Christian-Ehrlicher

They are, please recheck.

I did, and they are not.

Because you use the macro wrong:

I know I'm using the macro wrong, but it is the only way I have found to get the signaling between threads to work.

Q_DECLARE_METATYPE(MyNamespace::MyEnum)
Q_DECLARE_METATYPE(MyNamespace::MyEnum2)
Q_DECLARE_METATYPE(MyNamespace::MyStruct)
Q_DECLARE_METATYPE(MyNamespace::MyStruct2)

void MetaRegister::RegisterAllOfTheThings()
{
qDebug() << "Registering meta type: " << qRegisterMetaTypeMyNamespace::MyEnum();
qDebug() << "Registering meta type: " << qRegisterMetaTypeMyNamespace::MyEnum2();
qDebug() << "Registering meta type: " << qRegisterMetaTypeMyNamespace::MyStruct();
qDebug() << "Registering meta type: " << qRegisterMetaTypeMyNamespace::MyStruct2();
}

If I use this code above, I get this:
alt text

Christian Ehrlicher

Please push the code with my changes so others can test it

Palli

@Christian-Ehrlicher Done

Christian Ehrlicher

Ah, you still forget to fully qualify the enums in the slots as I said in my first post. I did this locally.

Palli

@Christian-Ehrlicher

I don't quite follow, are you talking about in the Receiver class?

class Receiver : public QObject
{
    Q_OBJECT

    public slots:
        void OnGettingEnum(MyNamespace::MyEnum e) {
            qDebug() << "Received on thread: " << QThread::currentThread();
            qDebug() << "Got the MyEnum: " << static_cast<int>(e);
        }
        void OnGettingEnum2(MyNamespace::MyEnum2 e) {
            qDebug() << "Received on thread: " << QThread::currentThread();
            qDebug() << "Got the MyEnum2: " << static_cast<int>(e);
        }
        void OnGettingStruct(MyNamespace::MyStruct s) {
            qDebug() << "Received on thread: " << QThread::currentThread();
            qDebug() << "Got the MyStruct";
        }
        void OnGettingStruct2(MyNamespace::MyStruct2 s) {
            qDebug() << "Received on thread: " << QThread::currentThread();
            qDebug() << "Got the MyStruct2";
        }
};

Palli

@Christian-Ehrlicher

Ok, you are talking about the signals in the Sender class?

Changing this

    class Sender : public QObject
    {
        Q_OBJECT
    signals:
        void EmitEnum(MyEnum);
        void EmitEnum2(MyEnum2);
        void EmitStruct(MyStruct);
        void EmitStruct2(MyStruct2);
    };

to this

    class Sender : public QObject
    {
        Q_OBJECT
    signals:
        void EmitEnum(MyNamespace::MyEnum);
        void EmitEnum2(MyNamespace::MyEnum2);
        void EmitStruct(MyNamespace::MyStruct);
        void EmitStruct2(MyNamespace::MyStruct2);
    };

fixes it.

Christian Ehrlicher

@Palli said in Emitting enum class in namespace not working:

Ok, you are talking about the signals in the Sender class?

Yes:

forgot to add the namespace to your signal - otherwise there would have been a warning about my_namespace ::my_enum and not my_enum.

Please mark the topic as solved then.

Palli

@Christian-Ehrlicher Done, thanks for you help