[comp.cog-eng] Scroll-Bars

roberts@cognos.UUCP (Robert Stanley) (01/11/90)

In article <581@cadlab.cadlab.de> chas@cadlab.UUCP (Charles White) writes:
   (Quoting an un-named previous poster)
>> Anyway, how can anyone scroll a window using a one button mouse?  (:-)
>
>That was a joke?? Why on earth would anyone implement a scrollbar that
>used more then one button?
>
>Chas
>chas@cadlab.de

I am not sure whether this question of Charles's is serious or not, but
it raises a point in which I have some interest.

I have regularly used systems which had the thumb-wheel scrollbar concept
(the scroll reference bar is also a positionable slider) and systems where
the scroll-bar itself was only a position indicator.  Equally, I have used
systems where you had to click on a direction indicator to trigger
scrolling, and some which scrolled in directions triggered by specific
combinations/choices of mouse buttons.  In reference to the previous post,
having a single scroll hot-spot per scrollbar and using the left/right
mouse button to select scroll direction is my least favourite paradigm.

What interests me is the fact that no concensus appears to have arisen.
For example, the HyperCard programming community have spent a lot of time
discussing the issues of scrollbar implementation, and frequently seem to be
edging towards concepts that are divergent from the Mac toolbox scrollbar.
In light of these observations, are there answers to any of the following
questions:

  a) Do window management system (WMS) vendors typically provide mechanisms
     to alter, suppress, or over-ride their "standard" scrollbar mechanisms?

  b) Do WMS vendors typically provide only a primitive function toolkit,
     insisting that developers implement scrollbars themselves?

  c) Do WMS vendors treat scrollbars in their style guides, and if so with
     what emphasis?

  d) Does the user culture for a WMS typically have strong feelings about
     scrollbars?

  e) If the WMS vendor has a style guide treatment of scrollbars, does the
     user culture support this treatment or does it regularly countenance
     alternate implementations?

  f) Where one vendor offers multiple WMSs (e.g., Sunview, NeWS, Openlook
     from Sun Microsystems; Windows 2, Windows 3, OS/2 PM from Microsoft)
     Do they treat scrollbars consistently across all WMSs?

There are obvioulsy alternate panning mechanisms to scrollbars, which have
always struck me as awkward when more than one axis is involved.  Does
anyone have any feelings as to whether such mechanisms (assuming an
effective implementation) could safely be offered *instead* of scrollbars?

Finally, are there any published studies on the effectiveness of scrollbar
techniques for indicating local position within larger 1-D and 2-D data
spaces?  Also, are there published references for alternative position-
indicating mechanisms?

What triggered this was a background discussion on portability of a WMS-
specific application (in this case OS/2 Presentation Manager) to other
WMS environments.  Given that scrollbar management requires considerable
program code under some WMSs, I became curious about the practicality of
an application-specific paradigm for 1-D and 2-D scrolling/panning.

I know this is not very important in the grand scheme of things, but if
anyone has real knowledge, or can point me to reasonably topic-specific
references, I would be grateful.  E-mail and I will summarize.

Robert_S
-- 
 Robert Stanley   UUCP: uunet!mitel!sce!cognos!roberts
 Cognos, Inc.     INET: roberts%cognos.uucp@uunet.uu.net
 (Research)      Voice: (613) 738-1338 x6115 

jdudeck@polyslo.CalPoly.EDU (John R. Dudeck) (01/13/90)

In article <7836@cognos.UUCP> roberts@cognos.UUCP (Robert Stanley) writes:
>having a single scroll hot-spot per scrollbar and using the left/right
>mouse button to select scroll direction is my least favourite paradigm.

Now I am not a Mac user, I have a PC clone with a 3-button Logitech
mouse.  I have found that by far the easiest scroll bar scheme I have
ever used is in the POINT editor by Logitech.  In this program the scroll bar
is along the screen border, so that you can hit it without having to worry
about going too far (assuming your window that you are scrolling fills the
screen, which it may not...), and then click the left and right buttons to
scroll up and down.  If you point to a specific location on the scroll bar
and press the middle button, it jumps to that relative location in the text.

With this approach there is no dragging of the locator thingy on the scroll
bar.  And as long as you are anywhere on the scroll bar you can scroll by
clicking a mouse button.  I find this extremely easy to use, because I can
do it without aiming.  I strongly detest every other scroll bar I have ever
tried to use, including the Macs that I have tried.


-- 
John Dudeck                           "You want to read the code closely..." 
jdudeck@Polyslo.CalPoly.Edu             -- C. Staley, in OS course, teaching 
ESL: 62013975 Tel: 805-545-9549          Tanenbaum's MINIX operating system.