Overridden pos() in QGraphicsItem to link to QAbstractItemModel

[lrb]

Gday,

I have subclassed QGraphicsPixmapItem in order to link the position of the item directly to a data model (subclassed from QAbstractItemModel).

I have overridden pos to return values from the model using appropriate QModelIndex objects (I am using PySide for Qt 4.8):


def pos(self):
x = self.model.data(self.x_index)
y = self.model.data(self.y_index)
return QPointF(x, y)

However, pos is never called! I assumed the view (via the scene) would call pos for each item when drawing, however from the source it looks like the view/scene gets the position of a QGraphicsItem directly through 'd_ptr'.

Is what I am trying to do possible? I was hoping there was some method that would form the single point of access to pos but it looks like this is not the case.

Thanks in advance

[wysota]

pos() is not a virtual method so overriding it does not make sense.

[lrb]

Cheers. It's a shame Qt wasn't implemented that way, would've made it simple to link graphics items to data models.

[wysota]

I do not agree. pos() is merely a getter for part of the internal item matrix. If you want to control position of an item through a model, you can freely do that by teaching your model to use pos() and setPos() to modify the item position.