[Qt-interest] if i use QAbstractItemModel::beginMoveRows will selection track moved rows?

[Ross Bencina]

Hi

I have some tables representing a sparse array. The tables allow elements to 
be dragged between cells. I've just ported this to use the model-view 
classes (previously I used QTableWidget).

I have drag and drop semantics somewhat like a list, where dragging an item 
to an in-use row re-shuffles items between existing cells, to support 
reordering in non-spares lists. For example:

BEFORE:

row
[1] item A
[2] item B
[3] item C
[4] item D

dragging item A to cell D moves all other items up like so:

AFTER:

row
[1] item B
[2] item C
[3] item D
[4] item A

My problem is that after the drag and drop operation, item A is no longer 
selected because I am using emit dataChanged() in my model to invalidate the 
rows. Question: if I instead used beginMoveRows()/endMoveRows() then would 
the selection update correctly?

In any case, the above example is not a contiguous move since 
source={1,2,3,4} and destination={4,1,2,3}. How can I deal with this? or 
should I just hack my model to directly modify the selection after a 
drag-and-drop operation?

Thanks

Ross.