costum QWidget with border-image in style sheet

[qt fan]

hello,

i have a simple class that derives from QWidget.
the paint event looks like this:

void ssbgtest::paintEvent(QPaintEvent *)
 {
     QStyleOption opt;
     opt.init(this);
     QPainter p(this);
     style()->drawPrimitive(QStyle::PE_Widget, &opt, &p, this);
 }

void ssbgtest::paintEvent(QPaintEvent *)
 {
     QStyleOption opt;
     opt.init(this);
     QPainter p(this);
     style()->drawPrimitive(QStyle::PE_Widget, &opt, &p, this);
 }

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well, this paintevent lets me use background-image in the style sheet.

but i need a border-image, because it will then resize the image when you resize the window. background-image tiles the image.

what i need is the code to provide this feature for my simple class. i guess its only about the primitiv element, but which is the right to draw?

greetz qt fan