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QObject::connect returns false

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  • JonBJ JonB

    @SPlatten said in QObject::connect returns false:

    @JonB , I have a break point in the debugger after the connect and can see it contains false.

    Noooo.
    Like I said, print it out........

    SPlattenS Offline
    SPlattenS Offline
    SPlatten
    wrote on last edited by
    #21

    @JonB, just did that adding:

    qDebug() << "connect: " << blnRC;
    

    Shown in console as:

    connect: false
    

    Kind Regards,
    Sy

    JonBJ 2 Replies Last reply
    0
    • SPlattenS SPlatten

      @JonB, just did that adding:

      qDebug() << "connect: " << blnRC;
      

      Shown in console as:

      connect: false
      
      JonBJ Offline
      JonBJ Offline
      JonB
      wrote on last edited by
      #22

      @SPlatten
      OK, damn!
      Just I warn you now: do not rely on what you see in the debugger for values of variables...!

      1 Reply Last reply
      0
      • SPlattenS SPlatten

        @KroMignon I will look at the generated moc files, but as you can see from my posts the prototypes are identical.

        KroMignonK Offline
        KroMignonK Offline
        KroMignon
        wrote on last edited by
        #23

        @SPlatten said in QObject::connect returns false:

        I will look at the generated moc files, but as you can see from my posts the prototypes are identical.

        Are you sure header files are in HEADERS in your PRO file?
        Did you (re)run qmake?
        You could also try to remove the build directory to force moc re-run.

        It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

        1 Reply Last reply
        2
        • SPlattenS SPlatten

          @JonB, just did that adding:

          qDebug() << "connect: " << blnRC;
          

          Shown in console as:

          connect: false
          
          JonBJ Offline
          JonBJ Offline
          JonB
          wrote on last edited by
          #24

          @SPlatten
          Like I said, have you done a delete and fresh rebuild?
          Does clsTimeEmu have Q_OBJECT in it?

          1 Reply Last reply
          0
          • SPlattenS Offline
            SPlattenS Offline
            SPlatten
            wrote on last edited by
            #25

            @J-Hilk , @JonB , @KroMignon , I've looked at both moc files, moc_clsTimeEmu.cpp has the signal:

            // SIGNAL_0
            void clsTimeEmu::epoch(int _t1)
            {
                void *_a[] = { 0, const_cast<void*>reinterpret_cast<const void*>(&_t)) };
                QMetaObject::activate(this, &staticMetaObject, 0, _a);
            }
            

            moc_clsSchdSrv.cpp does not have anything that looks like the slot, no mention of updateTime at all, why ?

            Kind Regards,
            Sy

            J.HilkJ KroMignonK JonBJ 3 Replies Last reply
            0
            • SPlattenS SPlatten

              @J-Hilk , @JonB , @KroMignon , I've looked at both moc files, moc_clsTimeEmu.cpp has the signal:

              // SIGNAL_0
              void clsTimeEmu::epoch(int _t1)
              {
                  void *_a[] = { 0, const_cast<void*>reinterpret_cast<const void*>(&_t)) };
                  QMetaObject::activate(this, &staticMetaObject, 0, _a);
              }
              

              moc_clsSchdSrv.cpp does not have anything that looks like the slot, no mention of updateTime at all, why ?

              J.HilkJ Offline
              J.HilkJ Offline
              J.Hilk
              Moderators
              wrote on last edited by J.Hilk
              #26

              @SPlatten well, can you post more of the clsSchdSrv header ?


              Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


              Q: What's that?
              A: It's blue light.
              Q: What does it do?
              A: It turns blue.

              SPlattenS 1 Reply Last reply
              0
              • SPlattenS SPlatten

                @J-Hilk , @JonB , @KroMignon , I've looked at both moc files, moc_clsTimeEmu.cpp has the signal:

                // SIGNAL_0
                void clsTimeEmu::epoch(int _t1)
                {
                    void *_a[] = { 0, const_cast<void*>reinterpret_cast<const void*>(&_t)) };
                    QMetaObject::activate(this, &staticMetaObject, 0, _a);
                }
                

                moc_clsSchdSrv.cpp does not have anything that looks like the slot, no mention of updateTime at all, why ?

                KroMignonK Offline
                KroMignonK Offline
                KroMignon
                wrote on last edited by
                #27

                @SPlatten said in QObject::connect returns false:

                moc_clsSchdSrv.cpp does not have anything that looks like the slot, no mention of updateTime at all, why ?

                Some time Qt-Creator do not detect changes is HEADERS files, so moc will not be re-run.
                This is why I suggest you to try to re-run yourself qmake and, if this not help, remove the build directory (as also suggested by @JonB ) to force full rebuild (with moc).

                But first, make sure all headers are present in HEADERS of your PRO file.

                It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

                SPlattenS 1 Reply Last reply
                0
                • J.HilkJ J.Hilk

                  @SPlatten well, can you post more of the clsSchdSrv header ?

                  SPlattenS Offline
                  SPlattenS Offline
                  SPlatten
                  wrote on last edited by SPlatten
                  #28

                  @J-Hilk , clsSchdSrv.h, still a early work in progress:

                  class clsSchdSrv : public QTimer {
                      Q_OBJECT
                  
                  public:
                      explicit clsSchdSrv(QObject* pParent = 0);
                      void kick();
                  
                  public slots:
                      virtual void expired() = 0;
                  }
                  

                  Sorry, should have added:

                  class clsTimeSync : public clsSchdSrv {
                  public:
                      explicit clsTimeSync();
                  
                  public slots:
                      virtual void expired();
                      void updateTime(int intTimeNow);
                  }
                  

                  Kind Regards,
                  Sy

                  jsulmJ J.HilkJ JonBJ KroMignonK 4 Replies Last reply
                  0
                  • SPlattenS SPlatten

                    @J-Hilk , @JonB , @KroMignon , I've looked at both moc files, moc_clsTimeEmu.cpp has the signal:

                    // SIGNAL_0
                    void clsTimeEmu::epoch(int _t1)
                    {
                        void *_a[] = { 0, const_cast<void*>reinterpret_cast<const void*>(&_t)) };
                        QMetaObject::activate(this, &staticMetaObject, 0, _a);
                    }
                    

                    moc_clsSchdSrv.cpp does not have anything that looks like the slot, no mention of updateTime at all, why ?

                    JonBJ Offline
                    JonBJ Offline
                    JonB
                    wrote on last edited by
                    #29

                    @SPlatten
                    We have all said several times to try a complete delete and re-build.....

                    1 Reply Last reply
                    0
                    • SPlattenS SPlatten

                      @J-Hilk , clsSchdSrv.h, still a early work in progress:

                      class clsSchdSrv : public QTimer {
                          Q_OBJECT
                      
                      public:
                          explicit clsSchdSrv(QObject* pParent = 0);
                          void kick();
                      
                      public slots:
                          virtual void expired() = 0;
                      }
                      

                      Sorry, should have added:

                      class clsTimeSync : public clsSchdSrv {
                      public:
                          explicit clsTimeSync();
                      
                      public slots:
                          virtual void expired();
                          void updateTime(int intTimeNow);
                      }
                      
                      jsulmJ Offline
                      jsulmJ Offline
                      jsulm
                      Lifetime Qt Champion
                      wrote on last edited by
                      #30

                      @SPlatten You should see a warning at runtime when connect is executed: what does it say?

                      https://forum.qt.io/topic/113070/qt-code-of-conduct

                      1 Reply Last reply
                      0
                      • KroMignonK KroMignon

                        @SPlatten said in QObject::connect returns false:

                        moc_clsSchdSrv.cpp does not have anything that looks like the slot, no mention of updateTime at all, why ?

                        Some time Qt-Creator do not detect changes is HEADERS files, so moc will not be re-run.
                        This is why I suggest you to try to re-run yourself qmake and, if this not help, remove the build directory (as also suggested by @JonB ) to force full rebuild (with moc).

                        But first, make sure all headers are present in HEADERS of your PRO file.

                        SPlattenS Offline
                        SPlattenS Offline
                        SPlatten
                        wrote on last edited by
                        #31

                        @KroMignon, I deleted the content of the build folder , checking for any hidden files, then ran clean, remake and build, same results.

                        Kind Regards,
                        Sy

                        1 Reply Last reply
                        0
                        • SPlattenS SPlatten

                          @J-Hilk , clsSchdSrv.h, still a early work in progress:

                          class clsSchdSrv : public QTimer {
                              Q_OBJECT
                          
                          public:
                              explicit clsSchdSrv(QObject* pParent = 0);
                              void kick();
                          
                          public slots:
                              virtual void expired() = 0;
                          }
                          

                          Sorry, should have added:

                          class clsTimeSync : public clsSchdSrv {
                          public:
                              explicit clsTimeSync();
                          
                          public slots:
                              virtual void expired();
                              void updateTime(int intTimeNow);
                          }
                          
                          J.HilkJ Offline
                          J.HilkJ Offline
                          J.Hilk
                          Moderators
                          wrote on last edited by
                          #32

                          @SPlatten if thats the header, than I as well fail to see the slot void updateTime(long); declaration ;)


                          Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


                          Q: What's that?
                          A: It's blue light.
                          Q: What does it do?
                          A: It turns blue.

                          1 Reply Last reply
                          0
                          • SPlattenS SPlatten

                            @J-Hilk , clsSchdSrv.h, still a early work in progress:

                            class clsSchdSrv : public QTimer {
                                Q_OBJECT
                            
                            public:
                                explicit clsSchdSrv(QObject* pParent = 0);
                                void kick();
                            
                            public slots:
                                virtual void expired() = 0;
                            }
                            

                            Sorry, should have added:

                            class clsTimeSync : public clsSchdSrv {
                            public:
                                explicit clsTimeSync();
                            
                            public slots:
                                virtual void expired();
                                void updateTime(int intTimeNow);
                            }
                            
                            JonBJ Offline
                            JonBJ Offline
                            JonB
                            wrote on last edited by JonB
                            #33

                            @SPlatten said in QObject::connect returns false:

                            public slots:
                            virtual void expired() = 0;

                            But you use SLOT(updateTime())?

                            Why are you showing us clsSchdSrv? Earlier you showed clsTimeSync?

                            SPlattenS 1 Reply Last reply
                            0
                            • SPlattenS SPlatten

                              @J-Hilk , clsSchdSrv.h, still a early work in progress:

                              class clsSchdSrv : public QTimer {
                                  Q_OBJECT
                              
                              public:
                                  explicit clsSchdSrv(QObject* pParent = 0);
                                  void kick();
                              
                              public slots:
                                  virtual void expired() = 0;
                              }
                              

                              Sorry, should have added:

                              class clsTimeSync : public clsSchdSrv {
                              public:
                                  explicit clsTimeSync();
                              
                              public slots:
                                  virtual void expired();
                                  void updateTime(int intTimeNow);
                              }
                              
                              KroMignonK Offline
                              KroMignonK Offline
                              KroMignon
                              wrote on last edited by
                              #34

                              @SPlatten said in QObject::connect returns false:

                              clsSchdSrv.h, still a early work in progress:

                              I am not sure, you can declare a slot as virtual.
                              I would change this to:

                              class clsSchdSrv : public QTimer {
                                  Q_OBJECT
                              
                              public:
                                  explicit clsSchdSrv(QObject* pParent = 0);
                                  void kick();
                              
                              public:
                                   virtual void  onExpired() = 0;
                              public slots:
                                  void expired() {  onExpired(); } 
                              }
                              

                              It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

                              1 Reply Last reply
                              0
                              • JonBJ JonB

                                @SPlatten said in QObject::connect returns false:

                                public slots:
                                virtual void expired() = 0;

                                But you use SLOT(updateTime())?

                                Why are you showing us clsSchdSrv? Earlier you showed clsTimeSync?

                                SPlattenS Offline
                                SPlattenS Offline
                                SPlatten
                                wrote on last edited by
                                #35

                                @JonB , please see the edited post which includes the derived class, sorry.

                                Kind Regards,
                                Sy

                                J.HilkJ KroMignonK JonBJ 3 Replies Last reply
                                0
                                • SPlattenS SPlatten

                                  @JonB , please see the edited post which includes the derived class, sorry.

                                  J.HilkJ Offline
                                  J.HilkJ Offline
                                  J.Hilk
                                  Moderators
                                  wrote on last edited by J.Hilk
                                  #36

                                  @SPlatten your derived class will need the Q_OBJECT macro as well, if it defines slots/signals


                                  Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


                                  Q: What's that?
                                  A: It's blue light.
                                  Q: What does it do?
                                  A: It turns blue.

                                  SPlattenS 1 Reply Last reply
                                  1
                                  • SPlattenS SPlatten

                                    @JonB , please see the edited post which includes the derived class, sorry.

                                    KroMignonK Offline
                                    KroMignonK Offline
                                    KroMignon
                                    wrote on last edited by
                                    #37

                                    @SPlatten said in QObject::connect returns false:

                                    please see the edited post which includes the derived class, sorry.

                                    In this header signal signature is void updateTime(int) and not void updateTime(long)

                                    It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

                                    JonBJ SPlattenS 2 Replies Last reply
                                    0
                                    • SPlattenS SPlatten

                                      @JonB , please see the edited post which includes the derived class, sorry.

                                      JonBJ Offline
                                      JonBJ Offline
                                      JonB
                                      wrote on last edited by
                                      #38

                                      @SPlatten
                                      class clsTimeSync : public clsSchdSrv {
                                      Although updateTime() is only a slot and not a signal, you do not have Q_OBJECT in this class. Does it help if you do (and then rebuild from scratch)?

                                      1 Reply Last reply
                                      0
                                      • KroMignonK KroMignon

                                        @SPlatten said in QObject::connect returns false:

                                        please see the edited post which includes the derived class, sorry.

                                        In this header signal signature is void updateTime(int) and not void updateTime(long)

                                        JonBJ Offline
                                        JonBJ Offline
                                        JonB
                                        wrote on last edited by
                                        #39

                                        @KroMignon said in QObject::connect returns false:

                                        In this header signal signature is void updateTime(int) and not void updateTime(long)

                                        That's coz he has changed per earlier on.
                                        I agree we do not know for sure what his code is, but I think he dealt with that alteration.

                                        1 Reply Last reply
                                        0
                                        • J.HilkJ J.Hilk

                                          @SPlatten your derived class will need the Q_OBJECT macro as well, if it defines slots/signals

                                          SPlattenS Offline
                                          SPlattenS Offline
                                          SPlatten
                                          wrote on last edited by
                                          #40

                                          @J-Hilk , why? The class it inherits already has that.

                                          Kind Regards,
                                          Sy

                                          JonBJ KroMignonK 3 Replies Last reply
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