[Usability]Viewpoints on conditional formatting, anyone?

[Pavel Shevchenko <pavel telemetry-investments com>]

Jon K Hellan writes:
 > Hi,
 > 
 > Conditional formatting is a much requested feature which Excel,
 > OpenOffice and KSpread have. It lets you specify e.g that cells with
 > the string "blue" should appear red, and there are many, more
 > sensible, applications.
 > 
 > We have to design a GUI for conditional formatting in
 > Gnumeric. Excel's GUI is a natural starting point, but hopefully we
 > can do better. I've put up a description with screenshots of Excel's
 > GUI at http://domen.uninett.no/~jk/cfmt.html.
 > 
 > Excel is limited to up to 3 conditions. Is there a need for more, and
 > can this be done without making the GUI confusing?
 > 
 > Excel's GUI is dynamic, it starts with a frame for a single condition
 > and lets you add more as you need them, and delete when you change
 > your mind. OpenOffice always shows all 3, and has a check box to
 > indicate which ones are actually used. I like OpenOffice's way, but it 
 > won't work for a large or unlimited number of conditions.
 > 
 > Let the brainstorming begin.
 > 
 > Regards
 > 
 > Jon Kåre
 > 
 > _______________________________________________
 > gnumeric-list mailing list
 > gnumeric-list gnome org
 > http://mail.gnome.org/mailman/listinfo/gnumeric-list
 > 
I think Excel GUI is the exapmle of the bad user interface. Ideo of writing 
logical expression in the form of GUI looks strange. Basically you have list 
in the form:

Expression1 -- Format1
......................
ExpressionN -- FormatN

Then you evaluate expression starting from 1 to N and choose format which
corresponds to the first expression returning 1(TRUE). So, you can use
standard gnumeric expression parser/eval (less coding). Also this expression
will be regular gnumeric expression, so it can contain references to the other 
cells and use all available functions.

For the first design you can use up to say 10 rows containing text entry 
fields for expression and labels for the format. 

Pavel.