The dataChanged Signal Not Performing as Expected

[d_stranz]

Actually, it's top left and bottom right, inclusive. From the docs:

If the items are of the same parent, the affected ones are those between topLeft and bottomRight inclusive.

This implies that if only one item is changed, the topLeft and bottomRight indexes should be the same. But for a tree view, this is important:

If the items do not have the same parent, the behavior is undefined.

This implies that if multiple items in the tree are changing at the same time, then you would need to emit multiple dataChanged() signals if the items come from different parts of the tree.

Top left and bottom right also implies that the items changing are contiguous between those two limits.