Check if button was right clicked or left clicked?



  • I create and customize a new button when my "create button" button is pressed like this

    void MainWindow::on_btn_add_btn_clicked() {
            QPushButton *btn = new QPushButton(ui->frame_btn_list);
            connect(btn, SIGNAL(clicked()), SLOT(on_btn_clicked()));
    
            btn->setText(QString("New Button " + QString::number(total_buttons)));
            btn->move(0, 30*total_buttons);
            btn->resize(186, 30);
            btn->setStyleSheet(QString("redundant styling... ignore this"));
            btn->show();
    
            total_buttons += 1;
    }
    

    Simply but, what I need is a way to execute a function when one of the buttons that I've created with this function gets right clicked. I already have a way to check if it has been clicked (left clicked, by default) as you can see but now I need to know how to check if a button has been right clicked. Further I also need to know WHAT button has been right clicked, not just that a button has been right clicked! I solved this "what button has been clicked" issue with the default left click by using

         QPushButton * theButton = qobject_cast<QPushButton *> ( sender() );
    

    in the on_btn_clicked() function and then modifying and getting info from "theButton" in different ways since "theButton" is the same as the button that was pressed.

    I've seen a few ways online to do this but none connect and check if a SPECIFIC button (no other object such as a frame) has been right clicked.


  • Qt Champions 2018

    You won't get a click event when anything else but the left button is clicked. If you want to handle other mouse buttons too you need to override QPushButton::mousePressEvent()



  • Can you give an example of how to override the QPushButton::mousePressEvent()? I don't know how to handle two different outcomes like this in one override!

    Semi-relateable: do I have different options? I.e. can I override the clicked() signal or do I HAVE TO override the mousePressEvent in order to do this? Would it be messy if I created a new signal and connected a button twice?


  • Qt Champions 2018

    You have to override the mousePressEvent() as I already said in my post above. And the link I gave you also shows you how to check for the correct mouse button.


  • Lifetime Qt Champion

    Hi
    For your use case, you could add new signal to
    your derived QPushButton to allow it to emit
    rightclicked() and connect to that new signal outside
    to handle when its right-clicked.

    Note: its pretty uncommon to right click buttons in terms
    of user experience.



  • When I try to add the QPushButton mouseEventPress() function into my code and redefine it it gives this error

    member access into incomplete type 'QAbstractButtonPrivate'
    

  • Qt Champions 2018

    You should not add the code from QAbstractButton::mousePressEvent() - you should override the function. This is basic c++ knowledge explained e.g. here: https://www.programiz.com/cpp-programming/function-overriding



  • All I get when I try to override the function is

    non-friend class member 'mouseEventPress' cannot have a qualified name
    

  • Lifetime Qt Champion

    @legitnameyo
    show the code :)



  • class Derived: public QPushButton {
    public:
        QPushButton A;
        QAbstractButton B(Derived);
        QAbstractButton::mouseMoveEvent(QMouseEvent *e); // Error
    
        void QAbstractButton::mousePressEvent(QMouseEvent *e) // Error
        {
            Q_D(QAbstractButton);
            if (e->button() != Qt::LeftButton) {
                e->ignore();
                return;
            }
            if (hitButton(e->pos())) {
                setDown(true);
                d->pressed = true;
                repaint();
                d->emitPressed();
                e->accept();
            } else {
                e->ignore();
            }
        }
    };
    
    


  • @legitnameyo
    You cannot define a qualifier in declaration of a member method.

    class Derived : public QPushButton{
    public:
      //void QPushButton::mousePressEvent(QMouseEvent *e); // wrong
      void mousePressEvent(QMouseEvent *e); // right
    };
    

    Further, you should to define the construtor method of your class.
    Note: The construtor method is a function without return value and with same name of class.

    class Derived : public QPushButton{
    public:
       Derived(); // construtor
    }
    

    To accept signals and slot feature, you need to declare the Q_OBJECT inside your class.

    class Derived : QPushButton{
       Q_OBJECT
    ...
    };
    

    Below is an example code of how you should reimplement it using @mrjj idea.

    class CustomPushButton : public QPushButton
    {
        Q_OBJECT
    public:
        CustomPushButton(QWidget *parent = nullptr);
    
    protected:
       void	mousePressEvent(QMouseEvent *e) override;
       void mouseReleaseEvent(QMouseEvent *e) override;
    
    signals:
        void leftClicked();
        void rightClicked();
    };
    

    Now, you need to reimplement the mousePressedEvent and mouseReleaseEvent(if necessary) logic on your .cpp file



  • all I get from that class is

    :-1: error: symbol(s) not found for architecture x86_64
    :-1: error: linker command failed with exit code 1 (use -v to see invocation)
    

  • Qt Champions 2018

    @legitnameyo said in Check if button was right clicked or left clicked?:

    all I get from that class is

    This is no class, this is a class definition. You have to fill out the functions by yourself with the code you want to have - we won't write you your code...



  • I can't write out the functions since everything I want to override or change in QPushButton::mousePressEvent is private.



  • Solved it by creating a derivative of the CustomQPushButton class definition! Thanks!