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Re: css abuse

From: Al Gilman <asgilman@iamdigex.net>
Date: Tue, 28 Sep 1999 22:56:04 -0400
Message-Id: <199909290257.WAA17380@smtp2.mail.iamworld.net>
To: w3c-wai-er-ig@w3.org
Cc: asgilman@access.digex.net
At 08:08 PM 9/28/99 -0400, Leonard R. Kasday wrote:
>Here's the question that came up in todays conf call.
>Lets say an author defines some id's like

No, not IDs.  They want to repeat the colors for all new and old items on
the page.  They can't repeat IDs.  So they add 'new' and 'old' as values in
CLASS="token, token, token" on the new and old elements.  Then the style
selectors pull up and match class=old or class=new to set colors.

>and then sets up a style sheet to color text corresponding to "new" and
>You then have color used for meaning, violating wcag.

The way I read the WCAG it doesn't say color cannot be meaningful.  It just
says that there has to be another way the meaning is communicated if there
is meaning to the color.

Typically, browsers use color to distinguish visited from non-visited
links.  This is exposed in CSS by a system-generated property.

Here, the plain English meaning of the CLASS value is an equivalent for the
sense of the color.  The class token is a good name for the meaning.  Using
'old' and 'new' as CLASS values and then keying the colors to those classes
is as close as CSS comes to giving color a verbal meaning.  

I am sorry this got discussed as abuse.  This is about the highest and best
use of css we have figured out to date.

>Say you want to do the right thing, and assign a meaning to these id's,
>something like titles or captions.  Ideally this would be a declaration
>assigning titles to id's.  But I don't see anything like that in CSS. 
>You could kluge something by putting descriptive text at each instance, and
>making it invisible or visible depending on the style sheet, but is there
>any good sway to do it?
>Or does CSS make it easy to set up visual styles but impossible to directly
>assign meaning to them to them?

The meaning CSS assigns directly is the presentation behavior.  The way to
have a verbal common reference point for the visual and aural styling is to
use good mnemonics as the class names in the HTML that the styles select on.

>Leonard R. Kasday, Ph.D.
>Institute on Disabilities/UAP, and
>Department of Electrical Engineering
>Temple University
>Ritter Hall Annex, Room 423, Philadelphia, PA 19122
>(215) 204-2247 (voice)
>(800) 750-7428 (TTY)
Received on Tuesday, 28 September 1999 22:55:49 UTC

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