QGraphicsScene, QGraphicsView and QVBoxLayout() problem

Greetings everyone,

Every time I run it seems Qt Creator just stop working, when I commented out the line //mainWindow = new MainWindow(); But if the line is not commented out, MainWindow will keep appearing many times. Also to check, is the structure of the QGraphicsScene, QGraphicsView and QVBoxLayout correct because I cant seem to make the view to appear when MainWindow is being called in main.cpp.

thanks :)

MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent), keydown_left(false), keydown_right(false),scene(NULL), view(NULL)
{
    qDebug("MainWindow");
    //mainWindow = new MainWindow();
    //qsrand(QTime(0,0,0).secsTo(QTime::currentTime()));
    scene = new QGraphicsScene(mainWindow);
    view = new QGraphicsView(scene, mainWindow);

    scene->setSceneRect(-300, 0, 640, 360);
    scene->setItemIndexMethod(QGraphicsScene::NoIndex);
    Egg *egg = new Egg();

    QVBoxLayout *layout = new QVBoxLayout();

    for (int i = 0; i < ObjCount; ++i) {
        FlyingObj *Fo= new FlyingObj();
        Fo->setPos(::sin((i * 6.28) / ObjCount) * 500,
                   ::cos((i * 6.28) / ObjCount) * 500);
        scene->addItem(Fo);
    }
    egg->setPos((640-64)/2, 100);//16 - 2*16
    scene->addItem(egg);


    view->setRenderHint(QPainter::Antialiasing);
    view->setBackgroundBrush(QPixmap(":/bg.jpg"));
    //view->setViewportUpdateMode(QGraphicsView::BoundingRectViewportUpdate);
    view->setDragMode(QGraphicsView::NoDrag);
    view->setWindowTitle(QT_TRANSLATE_NOOP(QGraphicsView, "Egg game"));
    view->resize(640, 360);
    QObject::connect(scene, SIGNAL(keyPressEvent(QKeyEvent)), this, SLOT(keyPressEvent(QKeyEvent)));
    view->setH开发者_运维技巧orizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    view->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    view->setFrameStyle(QFrame::NoFrame);
    view->setFocusPolicy(Qt::NoFocus);
    view->setCacheMode(QGraphicsView::CacheBackground);
    view->showFullScreen();

    layout->addWidget(view);
    QWidget *w = new QWidget();
    w->setLayout(layout);
}

Try to include main function in the project, usually defined separately in a file: Main.cpp, in which it instantiates your MainWindow class:

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

Uncommenting mainWindow in the MainWindow constructor is a recursive call, and incorrect way in this context. Lastly, try to change:

    layout->addWidget(view);
    QWidget *w = new QWidget();
    w->setLayout(layout);

into:

   setLayout(layout);