Q_OBJECT compile error... T^T

[Kycho]

If I comment out the line that contains Q_OBJECT, it compiles fine. (but, SLOT does not work.)

I have found a case that has experienced similar problems, but I don't know how to apply it to this source.

please help me

.h file

#ifndef ROOMBUTTON_H
#define ROOMBUTTON_H
#include <QPushButton>

class RoomButton : public QPushButton
{
    Q_OBJECT // This line is error..

public:
    RoomButton();


public slots:
    void roomClicked();

signals:
    void textChanged(QString &str);

private:
    QString temp;


};

#endif // ROOMBUTTON_H

.cpp file

#include "roombutton.h"
#include <QPushButton>

RoomButton::RoomButton()
{
    QSizePolicy sizePolicy2(QSizePolicy::Minimum, QSizePolicy::Preferred);
    this->setSizePolicy(sizePolicy2);

    QFont font = this->font();
    font.setPointSize(24);
    this->setFont(font);

    QObject::connect(this,SIGNAL(clicked()),
            this,SLOT(roomClicked()));
}

void RoomButton::roomClicked()
{
    if (temp != this->text()) {
    temp = this->text();
    emit textChanged(temp);
    }
}

void RoomButton::textChanged(QString &str){
}

compile error code

roombutton.cpp:4: error: undefined reference to `vtable for RoomButton'

Thanks in advance for your help.

[JKSH]

@Kycho said in Q_OBJECT compile error... T^T:

compile error code

roombutton.cpp:4: error: undefined reference to `vtable for RoomButton'

You have some stale files in the build directory. There are a few different ways to fix it:

• Click Build > Clean Project _____, OR
• Manually delete your build folder, OR
• Click Build > Run qmake (assuming you're using qmake)

[Kycho]

@JKSH
Thank you so much for solving the problem.

[J.Hilk]

@Kycho
There is more to fix (the constructor) or you'll end up with strange errors later down the road.

public:
    RoomButton();

//to
   explicit RoomButton(QWidget *parent = nullptr);

RoomButton::RoomButton()
{
    QSizePolicy sizePolicy2(QSizePolicy::Minimum, QSizePolicy::Preferred);
    this->setSizePolicy(sizePolicy2);

    QFont font = this->font();
    font.setPointSize(24);
    this->setFont(font);

    QObject::connect(this,SIGNAL(clicked()),
            this,SLOT(roomClicked()));
}

// to
RoomButton::RoomButton(QWidget *parent)  : QPushButton(parent);
{
    QSizePolicy sizePolicy2(QSizePolicy::Minimum, QSizePolicy::Preferred);
    this->setSizePolicy(sizePolicy2);

    QFont font = this->font();
    font.setPointSize(24);
    this->setFont(font);

    QObject::connect(this,SIGNAL(clicked()),
            this,SLOT(roomClicked()));
}

[Kycho]

@J.Hilk

I modified the source according to your advice.
Thank you so much!!