QGraphicsView setSceneRect() problems

[tarantulae]

When I set the scene rect to the same rect of the viewport:

@mCanvasScene->setSceneRect(mCanvasView->viewport()->rect());@

The QGraphicsView creates scrollbars in the widget, but if the scene is the same size of the viewport why there are scrollbars ? It seems that the rect() from the viewport isn't the correct size of the viewport area. Does anyone saw this issue ?

Thank you !