I have a large tree view where users will often want to fully expand or collapse a particular tree. I'm providing a context menu with both of these choices, but I'd also like to allow the user to hold down a keyboard modifier while clicking on the toggle to fully expand or collapse the nodes under it. (e.g. alt-click, or shift-click)
Is there any convention for this that you have seen in other applications?
What modifier(s) should I use?
My app is currently targeting Windows, so conventions there are most important. (Answers for other platforms are also welcome, though, for others who may find this question.) If you can name specific applications providing this functionality, I would appreciate it.
Edit: I have found that in Windows XP and 7 you can select an item in the tree view of Explorer and use numpad-* to fully expand the tree. Sadly, my tree view does not have selectable items, and so this convention cannot be supported.