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Weird signal and slot problem

  • hello, I'm trying to conect a signal from an object, to a signal on a thread, both QString. I make the conection on main window, that is my code (in mainwindow):

        gMsg = new getmsg(this,mWSize.x,mWSize.y);
        serPort = new sport(this);

    the compiler get the next error that i could not solved, deleting the temporary compile directory and right botton on project + clean

    I ask you please help on Monday, the boss will give me the talk of dismissal (), but I want the program end.

    Thanks in advance

    moc_sport.obj:-1: error: LNK2019: unresolved external symbol "public: void __cdecl sport::updateMsg(class QString)" (?updateMsg@sport@@QEAAXVQString@@@Z) referenced in function "private: static void __cdecl sport::qt_static_metacall(class QObject *,enum QMetaObject::Call,int,void * *)" (?qt_static_metacall@sport@@CAXPEAVQObject@@W4Call@QMetaObject@@HPEAPEAX@Z)

  • I'm not 100% which one of these causes the error but:

    • Make sure that your sport class has the Q_OBJECT macro
    • If you added the Q_OBJECT macro after the first compile, you must manually re-run qmake by Build -> Run qmake
    • Make sure that your sport class actually has the updateMsg() method implemented
    • Make sure that your sport class actually lists the updateMsg() method in the public slots section

    I hope that helps.

  • Thank you very much for your help.

    Finally was that i forget sport:: on

    void sport::updateMsg(QString newMsg){


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