QGraphicsView Inheritance



  • I am trying to implement a mouse scroll zoom function as a child class for QGraphicsView.
    When compiling I get the error: " error C2247: 'QObject::setObjectName' not accessible because 'CustomGraphicsView' uses 'private' to inherit from 'QGraphicsView'".

    This occurs for every function call from QGraphicsView.

    I used QtCreator's promote to to change my qgraphicsview to my customgraphicsview class.
    My code is as follows:

    customgraphicsview.h

    #ifndef CUSTOMGRAPHICSVIEW_H
    #define CUSTOMGRAPHICSVIEW_H
    
    #include <QGraphicsView>
    #include <QtWidgets>
    #include <QWidget>
    
    class CustomGraphicsView : QGraphicsView
    {
    public:
        CustomGraphicsView(QWidget* parent = 0);
    
    protected:
        virtual void wheelEvent(QWheelEvent *event);
    private:
        const double scaleFactor = 1.2
    };
    
    #endif // CUSTOMGRAPHICSVIEW_H
    
    

    customgraphicsview.cpp

    #include "customgraphicsview.h"
    
    CustomGraphicsView::CustomGraphicsView(QWidget *parent) : QGraphicsView(parent)
    {
    
    }
    
    void CustomGraphicsView::wheelEvent(QWheelEvent *event)
    {
        setTransformationAnchor(QGraphicsView::AnchorViewCenter);
        if (event->delta() > 0) {
            scale(scaleFactor, scaleFactor);
        } else {
            scale(1/scaleFactor, 1/scaleFactor);
        }
    }
    
    

    I am currently on Qt 5.7 using MSVC.



  • change inheritance to public:

    class CustomGraphicsView : public QGraphicsView


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