Scrollbar live updating

[Jeff Massung]

I've been trying, but can't seem to find a way to live update a scrollbar.
What I'd like to do it have a scroll value whose min and max values actually
equate to font sizes in a modeless preferences stack. As the user slides it
around, they see the font change size live. But I can't see to get this to
work.

Has anyone else done this and can lend some tips?

Thanks!

Jeff M.