Qt QGraphicsView not showing the scene

Question

I am new to Qt. I got a problem. I do not want to use Qt forms to create QGprahics view I just want to code it and I can't get it work.

here is my code:

main.cpp:

#include "mainwindow.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();

    return a.exec();
}

mainwindow.cpp

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
{
    scene = new QGraphicsScene(this);
    scene->setSceneRect(600,480,600,480);

    QGraphicsEllipseItem * ellipse;
    QPen pen(Qt::red);
    QBrush brush(Qt::blue);

    ellipse = scene->addEllipse(150,150,100,100,pen, brush);

    view = new QGraphicsView(scene,this);

    setCentralWidget(view);

}

MainWindow::~MainWindow()
{
    delete view;
    delete scene;
}

view and scene are privete members of class MainWindow.

Program just shows white screen but there is no ellipse there.

any suggestions what am I doing wrong? Thanks in advance!

Answer 1

I think that you problem is scene->setSceneRect(600,480,600,480);.

Your ellipse is created outside of the view.