[Qt-interest] Using QGraphicsLayouts inside QGraphicsWidgets

[Sean Harmer]

On Monday 27 June 2011 15:29:50 Schimkowitsch Robert wrote:
> > QGraphicsItem from which QGraphicsWidget inherited indirectly is
> 
> responsible
> 
> > for deleting any child graphics items. This is analogous to how
> 
> QObject
> 
> > derived items delete their children in the rest of Qt.
> 
> And this is what confuses me. Because QGraphicsLinearLayout is no
> QGraphicsItem subclass. How does it fit into the parent/child hierarchy?
> Why should QGraphicsItem (which knows nothing of layouts) care about a
> QGraphicsLayoutItem?

The parent QGraphicsWidget manages both the layout and the child widgets. That 
is the child widgets have your top-level QGraphicsWidget as their parent and 
not the layout.

Take a look at the code in QGraphicsWidget destructor to see how and where it 
deletes the layout. 

The GraphicsItem destructor handles deletion of child QGraphicsItems.

HTH,

Sean