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[solved]He said "undefined reference to 'vtable for MyTask(class)' "



  • Would you help me? Thank you!
    My program is little,

    mytask.h

    #ifndef MYTASK_H
    #define MYTASK_H
    #include <QRunnable>
    #include <QObject>
    #include <QDebug>
    class MyTask : public QObject,public QRunnable//inherit object and runnable
    {
        Q_OBJECT
    public:
        MyTask();
    signals:
        void Result(int iNumber);//my signals
    
    protected:
        void run();
    };
    
    #endif // MYTASK_H
    
    

    mytask.cpp

    #include "mytask.h"
    
    MyTask::MyTask()//first error at here,it said: " error: undefined reference to `vtable for MyTask'"
    {
    
    }
    
    void MyTask::run()
    {
        qDebug()<<"Tesk Run...";
        int iNumber = 0;
        for(int i=0; i<100; ++i)
        {
            iNumber += i;
        }
        qDebug()<<"Task done!";
        emit Result(iNumber);//second at here it said:" error: undefined reference to `MyTask::Result(int)'"
    }
    

  • Lifetime Qt Champion

    Hi,

    Usually it's because you added/removed the Q_OBJECT macro without re-running qmake. Re-run it and you should be good to build.



  • @SGaist Yes,it is ok! I ran qmake and ran all,it is ok! thank you very much!


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