Notification of row expansion and row collapsed in GtkTreeView

["Padraig O'Briain" <Padraig Obriain Sun COM>]

I am trying to obtain notification of when a row in a GtkTreeView is expanded or 
collapsed. I have found the signals "expand_row" and "collapse_row".

However, it seems to me that these signals are emitted before the row is 
actually expanded or collapsed. Is there a reason why this signal could not be 
emitted after the actual expansion or collapse?

If I want to be notified after the actual expansion, do I need a new signals in 
GtkTreeView or can I call gtk_idle_add() in the signal handler for say, 
expand_row, to ensure that the row is actually expanded?

Padraig