I'm confused about writing into a TreeList

[fab|an]

Hi,

 I'm currently working on an SWT Viewer for TreeList. I want it to be able to display Editors for Items with which I can change data in the underlying list. I'm however confused how TreeList handles updates, since there are "virtual" and non-virtual happens.

For example: I have two Categories: A-B-C and A-B-D, which map to the following tree:

A
 B
  C
  D

What should happen when I call set on index 2 (=on the item B) in the TreeList? Which elements receive update events afterwards?
Does it make more sense in the TreeViewer to change the data in an element and call set? Or should I just fire update events?

fabian