Re: Gtk scrollbar: thumb too short

[Luc Teirlinck <teirllm@dms.auburn.edu>]

Robert Chassell wrote:

   I am puzzled.  Using 20.7, when I visit NEWS by typing `C-h n'
   (view-emacs-news) and then type `C-c C-t' (hide-body), the thumb grows
   bigger.

   When I then type `C-c C-a' (show-all), the thumb grows smaller.

That is because the total (visible and invisible) amount of text on
the screen increases or decreases.  This also seems to happen in
21.3.50, it just is harder to notice.  (C-c C-t seems to take an
awfully long time in Emacs-21.3.50 in the NEWS buffer.)
   
   I interpret this to mean that the thumb shows the portion of visible
   text shown in the window to all the visible text in the buffer.

No, because if you start with a full screen and make all text outside
your screen invisible, nothing happens to the thumb size.  So the
thumb does count invisible text as present in the buffer.

Stefan knows substantially more about the scrollbar than I do.  He
can correct me if I am wrong.  I believe I am right on this particular
issue however.  (We are talking about Emacs20.7, configured with with
./configure --prefix=/usr/local)

Sincerely,

Luc.