How to create a scrolled TreeView?

[Matthias Kaeppler <matthias finitestate org>]

Hi,

is there a way to make a TreeView have scrollbars without wrapping it in 
a Gtk::ScrolledWindow?

The problem is, my widget is supposed to behave exactly like a treeview 
(well, except that it's supposed to be scrollable and not resize itself 
to fit its content), and not like a window. If I derive from 
ScrolledWindow, I would have to delegate tons of signals, because there 
is no visible space between the treeview and the scrolled window, and 
thus all clicks and other actions always happen in the context of the 
treeview, but the client only has access to the embedding window.

This is especially problematic for drag and drop, because the dnd 
signals are fired by the treeview, and not the window comprising it, so 
getting a pointer to the desired widget by downcasting from the drag 
context (get_source_window()) always fails.

Because of these reasons, I don't want to derive from ScrolledWindow, 
but directly from TreeView. Is it still possible to get scrollbars?

Thanks,
Matthias