No, I thought you were using a custom model and had setData broken.

What about this? ( from QStandardItem::setData )
Qt Code: 
  1. QVariant oldValue = data(role);
  2.     if (value == oldValue)
  3.         return;
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As you can see no value is set if it is equal to the old one.

What values are in the model?
You are always setting QSize(0,0) and get it back.


(I'm using Qt 4.2.2 ).

Regards