class zoomPrintPreview : public QPrintPreviewWidget
{
protected:
void wheelEvent(QWheelEvent *event);

public:
zoomPrintPreview(QPrinter *printer = 0);
~zoomPrintPreview();
};

zoomPrintPreview::zoomPrintPreview(QPrinter *printer)
: QPrintPreviewWidget(printer)
{

}

zoomPrintPreview::~zoomPrintPreview()
{

}

void zoomPrintPreview::wheelEvent(QWheelEvent *event) {
if (event->modifiers()& Qt::ControlModifier) {
if (event->delta() > 0)
zoomIn();
else
zoomOut();
}
}