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Emitting enum class in namespace not working

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  • Christian EhrlicherC Christian Ehrlicher

    Please show your connect statement. Looks like you're using the old style connect and forgot to add the namespace to your signal - otherwise there would have been a warning about my_namespace ::my_enum and not my_enum. Fix your signal and use the new style connect.

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    Palli
    wrote on last edited by Palli
    #3

    @Christian-Ehrlicher
    The connection is something like this

    QObject::connet(my_class_ptr, &my_class::EmittMyEnum,
    some_other_class_ptr, &some_other_class::other_class_slot);
    

    But this connection is made in my_namespace , but some_other_class is not in my_namespace.

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    • Christian EhrlicherC Online
      Christian EhrlicherC Online
      Christian Ehrlicher
      Lifetime Qt Champion
      wrote on last edited by
      #4

      Your code above is not consistent with the enum naming and others. Please provide a minimal, compilable example so we can reproduce the issue.

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      • Christian EhrlicherC Christian Ehrlicher

        Your code above is not consistent with the enum naming and others. Please provide a minimal, compilable example so we can reproduce the issue.

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        P Offline
        Palli
        wrote on last edited by
        #5

        @Christian-Ehrlicher

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

        a8109696-e6d2-446d-8b09-f681ea3b238d-image.png

        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

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        • Christian EhrlicherC Online
          Christian EhrlicherC Online
          Christian Ehrlicher
          Lifetime Qt Champion
          wrote on last edited by
          #6

          @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>();
          }
          

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          • Christian EhrlicherC 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>();
            }
            
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            P Offline
            Palli
            wrote on last edited by
            #7

            @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

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            • Christian EhrlicherC Online
              Christian EhrlicherC Online
              Christian Ehrlicher
              Lifetime Qt Champion
              wrote on last edited by
              #8

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

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              • Christian EhrlicherC Christian Ehrlicher

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

                P Offline
                P Offline
                Palli
                wrote on last edited by
                #9

                @Christian-Ehrlicher Done

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                • Christian EhrlicherC Online
                  Christian EhrlicherC Online
                  Christian Ehrlicher
                  Lifetime Qt Champion
                  wrote on last edited by
                  #10

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

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                  • Christian EhrlicherC 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.

                    P Offline
                    P Offline
                    Palli
                    wrote on last edited by
                    #11

                    @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";
                            }
                    };
                    
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                    • Christian EhrlicherC 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.

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                      Palli
                      wrote on last edited by
                      #12

                      @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 EhrlicherC 1 Reply Last reply
                      0
                      • P 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 EhrlicherC Online
                        Christian EhrlicherC Online
                        Christian Ehrlicher
                        Lifetime Qt Champion
                        wrote on last edited by
                        #13

                        @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.

                        Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
                        Visit the Qt Academy at https://academy.qt.io/catalog

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                        • Christian EhrlicherC 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.

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                          P Offline
                          Palli
                          wrote on last edited by
                          #14

                          @Christian-Ehrlicher Done, thanks for you help

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