updating a dialog connected to a scroll-bar

[pshannon@iapetus.cv.nrao.edu (Paul Shannon)]

A simple question with a simple answer, I'm sure:

I have an editable-text-dialog-item which is the 'scrollee' of
a scroll-bar-dialog-item, and a generic function 

   scroll-bar-changed

that's called with every mouse event on the scoll-bar.  
scroll-bar-track-thumb-p is true.  When I put a format
statement in the scroll-bar-changed method, I see that the method
is truly  being called with every mouse event.  The problem is
that the text-dialog is not updated until the mouse events stop.
I call

   (set-dialog-item-text target (format nil "~d" current-value))

but the text doesn't change while the mouse is down.  How do I force
the update?  What principle lies behind the delay?

Thanks.

 - Paul Shannon
   pshannon@nrao.edu
   National Radio Astronomy Observatory
   Charlottesville, Virginia