Subclassing QGLWidget using Qt Creator error

Question

I'm trying to make a simple subclass of QGLWidget using Qt creator, I generated the .h and .cpp file using the Qt Creator wizard which generated the following code:

viewport.cpp

#include "viewport.h"

Viewport::Viewport(QObject *parent) :
    QGLWidget(parent)
{
}

viewport.h

#ifndef VIEWPORT_H
#define VIEWPORT_H

#include <QGLWidget>

class Viewport : public QGLWidget
{
    Q_OBJECT
public:
    explicit Viewport(QObject *parent = 0);

signals:

public slots:

};

#endif // VIEWPORT_H

I added QT += opengl to the .pro file which got rid of most of the errors but I'm left with two that I don't understand:

/projects/tree_gen/qt_project/tree_gen-build-desktop-Qt_4_8_4_in_PATH__System__Debug/../tree_gen/viewport.cpp:4: error: invalid conversion from 'QObject*' to 'QWidget*'

/projects/tree_gen/qt_project/tree_gen-build-desktop-Qt_4_8_4_in_PATH__System__Debug/../tree_gen/viewport.cpp:4: error:   initializing argument 1 of 'QGLWidget::QGLWidget(QWidget*, const QGLWidget*, Qt::WindowFlags)'

Ive not changed anything, just trying to compile what Qt gave me, any ideas?

Answer 1

QGLWidget is a widget and it takes am QWidget* as a parent, so it's a good idea to use that kind of parent for your widget class too: explicit Viewport(QWidget *parent = 0); //don't forget to modify the .cpp too