Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cwjcc!alpha.ces.cwru.edu!mitch
From: mitch@alpha.ces.cwru.edu (Mitchell N. Perilstein)
Newsgroups: comp.sys.mac.programmer
Subject: TrackControl Action Procs: Control Value Unavailable?
Message-ID: <447@cwjcc.CWRU.Edu>
Date: 2 Aug 89 00:09:26 GMT
Sender: news@cwjcc.CWRU.Edu
Reply-To: mitch@alpha.ces.cwru.edu (Mitchell N. Perilstein)
Organization: Case Western Reserve University
Lines: 19

Does anyone know how to get the value of a standard scrollbar from
within a TrackControl() callback procedure? 

If one either uses GetCtlValue(), or one looks at the contrlValue field
of the control record, it appears that the control value doesn't change
until TrackControl() is about to return (at mouse up).  If the value
of the control is needed at all times, including the time during which
it's being tracked, you're going to have a hard time.

Shouldn't TrackControl() continuously update this field as the indicator
is being dragged, to provide the most flexible programming interface? 

Or is what we see here the Standard User Interface telling us that
control changes should not be effected until the mouse button is released?


Mitchell N. Perilstein
 arpa:   mitch@alpha.ces.CWRU.edu
 usenet: {decvax,sun}!cwjcc!alpha!mitch