QGraphicsView question

[jpn]

can QGraphicsView hold several QGraphicsScenes at a time?

No, a QGraphicsView represents a single QGraphicsScene. You can adjust QGraphicsItem::zValue() if you want to make layers.

[xgoan]

Also, you can have multiples scenes in memory and change them in the GraphicsView

[Bitto]

Technically it's possible to write a QGraphicsSceneItem, if you want multiple scenes inside the same view. If you don't mind skipping the scrollbars, you do have everything available in QGraphicsScene's API to make an item:

QGraphicsItem::boundingRect: returns anything suitable / a subscene rect.
QGraphicsItem:aint: calls QGraphicsScene::render().

We actually have a registered suggestion for such an item, and we might provide one for 4.4.