QGraphicsView (OpenGL Viewport) issue with Stylesheet

[hamed_ta]

Hi I'm developing a graphical Qt application under windows I used QGraphicsView within a QOpenGLwidget for it's viewport the problem is when I don't use any Stylsheet it works well but if I use stylsheet in any parent of QGraphicsView the background doesn't refresh (repaint) anymore and if I draw a graphicsitem it doesn't remove until I resize the QGraphicsView! what do you think ? is it a bug in Qt 5.9.2 ? or there is a solution ? of course I need to use stylesheet in my app.

here is source code for the GraphicsView ...

#ifdef USE_OpenGL


    QSurfaceFormat format = QSurfaceFormat::defaultFormat();
    format.setProfile(QSurfaceFormat::CoreProfile);
    format.setDepthBufferSize(24);
    format.setStencilBufferSize(8);
    format.setSamples(4);
    format.setSwapBehavior(QSurfaceFormat::DoubleBuffer);
    m_viewPort->setFormat(format);

    ui->gV->setViewport(m_viewPort);
#else
    ui->gV->setCacheMode(QGraphicsView::CacheBackground);
#endif

ui->gV->setViewportUpdateMode(QGraphicsView::FullViewportUpdate);
ui->gV->setRenderHints(QPainter::Antialiasing| QPainter::HighQualityAntialiasing | QPainter::SmoothPixmapTransform| QPainter::TextAntialiasing);
ui->gV->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
ui->gV->setVerticalScrollBarPolicy  (Qt::ScrollBarAlwaysOff);
ui->gV->setTransformationAnchor(QGraphicsView::NoAnchor);
//ui->gV->setAutoFillBackground(false);
//ui->gV->setAttribute(Qt::WA_OpaquePaintEvent, true);
//ui->gV->setAttribute(Qt::WA_NoSystemBackground, true);

resize(boardBaseSize);
//ui->gV->resize(widgetBaseSize);

also if I don't use OpenGL view port it again works and if I set cacheMode to QGraphicsView::CacheBackground the it works again but it doesn't use OpenGL anymore !

thank you for your kind answers

[mrjj]

Hi
Well what do you use in the stylesheet?
If you exclude QGraphicsView and QOpenGLwidget does it still happen?

[hamed_ta]

Hi
I don't have any style for QGraphicsView and QOpenGLwidget in my stylesheet, if I only set background-color for any parent widget of the QGraphicsView widget it happen and I have background color for QWidget class so all other widgets including QGraphicsView and QOpenGLwidget inherit from it.

[mrjj]

Hi
As far as i know QOpenGLwidget do not use QStyle at all so
its not unexpected that stylesheet do not work on/with it.
So its not supported I guess.

[hamed_ta]

Hi

so what is the solution as I need to use the stylesheets for all other widgets ?

[mrjj]

@hamed_ta

Well, use names, types or or any of the specifiers. instead of the "hit them all"
QWidget type

http://doc.qt.io/qt-5/stylesheet-syntax.html

Maybe there is also something CSS2 selector syntax:

Not sure that "not" specifier is supported.

but there is always
QWidget[flat="true"]
syntax and you could just add that to the QGraphicsView and some property so it
wont be affected but all others does.

[hamed_ta]

@mrjj

OK very good solution I changed all the widget styles to QWidget[acceptDrops=false] and set acceptDrops to true in QGraphicsView and its parent so the style doesn't affect on it but there is another problem ,I have a frame which contains the QGraphicsView and I need to style the frame by background-color key, but when I do so, the The problem goes back again!

how can I set style to the frame without affecting the QGraphicsView ?

the stye is

background-color: qlineargradient(spread:reflect, x1:0.5, y1:1, x2:0.5, y2:0, stop:0 rgba(15, 21, 27, 255), stop:1 rgba(67, 74, 86, 255));
border-radius: 15px;
border-width : 0px;

[hamed_ta]

@hamed_ta

Oh I found it, I set the stylesheet of the Qframe to

QFrame[acceptDrops=false]
{
	background-color: qlineargradient(spread:reflect, x1:0.5, y1:1, x2:0.5, y2:0, stop:0 rgba(15, 21, 27, 255), stop:1 rgba(67, 74, 86, 255));
	border-radius: 15px;
	border-width : 0px;
}

thank you so much

[mrjj]

Super :)
Just as a note , you can add custom (dynamic) properties with the green + over the property list but
if you never need to use drag and drop that property is just as good.

[hamed_ta]

@mrjj

Super!