[QT4.1.1 XP] background image

[incapacitant]

I try to set the background of a widget to an image as indicated in Assistant in the
Porting to QT4 of setPaletteBackgroundPixmap :

QWidget *widget = new QWidget;
QPixmap pixmap(":/images/bArchi.png");
QPalette palette;
palette.setBrush(widget->backgroundRole(), QBrush(pixmap));
widget->setPalette(palette);
setCentralWidget(widget);

QWidget *widget = new QWidget;
QPixmap pixmap(":/images/bArchi.png");
QPalette palette;
palette.setBrush(widget->backgroundRole(), QBrush(pixmap));
widget->setPalette(palette);
setCentralWidget(widget);

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I played around with many combinations of the above code, but nothing will show my
image. The background remains unchanged...