QTreeView: emit dataChange when columns are rearranged

I did not know about it until recently: QTreeView allows user to manually rearrange columns by dragging them around. So if I have treeview with three columns:
A B C
user can rearrange them to be, say
C A B

I found out that Qt correctly requests the data in this case, i.e first it requests data for column 0 in the "original" view and it changes to requesting data for column "2" in "rearranged" view

So far so good. What I don't understand is how I should manually call "dataChange" signal. I mean, when data that I display in column "A" is changed programmatically I am emitting "dataChange" signal with QModelIndex pointing to column 0 (zero), which is "A" in "orignal" view. Should I track rearrangment of the columns and switch to dataChange with QModelIndex pointing to column 1 ("A" in rearranged view) or keep doing what I do regardless of how user moves columns around?

Thanks.

Column arrangement (or actually mapping) is only done by and in the view. You don't need to change the model in any way to support it. The view always asks the model based on the "logical" order of columns even if physical order is different.