How do I know an item's row or column spans in QGraphicsGridLayout

[lni]

QGraphicsGridLayout has a method

void addItem ( QGraphicsLayoutItem * item, int row, int column, int rowSpan, int columnSpan, Qt::Alignment alignment = 0 )

After adding the item, how can I know its rowSpan and columnSpan? I can't serialize and unserialize the graphics if I can't get the spans...


Thanks.