Don't impose event handling

[NicoG60]

Hi,
I have several issues with that bit of code.
First, I think it is better to let people subclass and override this method if they need and not impose the F key to be bound to a fullscreen feature. Maybe they want another key to toggle fullscreen, maybe they need osg to get the F key event.

Then I spotted an issue that might lead to a segfault? Not sure though but here is my point in the comment.

if(event->key() == Qt::Key_F)
{
    static QSize g;
    static QMargins sMargins;

    if(parent() && parent()->isWidgetType())
    {
        QMainWindow* _mainwindow = dynamic_cast<QMainWindow*>(parent());

        if(_mainwindow)
        {
            // Bla bla bla, fullscreen stuff...
        }
    }
    else
    {
        showNormal();
        setMinimumSize(g);

        /*
        
        Why that ?
        
        If we get here, first that can mean parent() is a nullptr.
        if parent() == nullptr, then the program will fall in this branch and
        segfault.

        Then, parent is not necessarly a main window. Can be any widget.
        Doing a dynamic cast here can return nullptr if parent() is not a
        mainwindow and segfault again.

        */ 
        QMainWindow* _mainwindow = dynamic_cast<QMainWindow*>(parent());
        _mainwindow->setCentralWidget(this);

        if(layout())
            layout()->setContentsMargins(sMargins);

        qApp->processEvents();
        setMinimumSize(QSize(1, 1));
    }
}
else // not 'F' key
{
    // forward event to renderer
    m_renderer->keyPressEvent(event);
}

I think it is better to let people handle that fullscreen feature as they want. They can have really different way of organising that widget into their app and maybe they want to be able to have more control over that.

[mathieu]

Hi @NicoG60,

Thanks for the PR, the removed code should probably best be transferred to a sample where the osgQOpenGLWidget is the central widget of a QMainWindow ?

[NicoG60]

Yeah I think that piece of code could be a good example with a mainwindow as a container.
Just I don't think it is relevant to bake it in the library itself.
I can provide a simple example for that if you want

[mathieu]

I can provide a simple example for that if you want

That would be awesome!