Re: managing alternatives

Al Gilman wrote:
>>> On 14/07/07, Al Gilman <Alfred.S.Gilman@ieee.org> wrote:
>>>> One suggestion has been that we add an @equivalent attribute to the
>>>> WAI-ARIA vocabulary.
>>>
>>> An equivalent attribute sounds like a good idea. What data type would
>>> it accept? 

One way of figuring this out would be to look at all of the
content/attribute types whose usage and future are hanging in the
balance in HTML 5 and are currently considered absent in the draft spec
but could unfortunately end up deleted (@summary, @longdesc etc) [1] .
These are attributes that were to provide the function of being easily
authored methods of delivering equivalent content. So if their future is
in the balance why not consider an attribute that uses a term that is
intuitive and helpful to the author?  In practice this may not stand
however for rich media like video etc as they already have new elements
proposed in HTML 5 spec <video> etc [2] but could be useful for images,
tables etc. Could @equivalent or @equal have some extra qualifying
attributes itself that identify it to the user agent as being related to
a particular type of content such as a table or image?

Element types could be abbreviated or identified numerically, 1 being an
image, 2 a table etc @equal1="More info about the table", @equal2="More
longdesc type info about the image". Though this is less intuitive and
could probably not be considered 'high level' authoring.

Another approach could be that the attributes 'mode' is triggered by its
associated element (context of use) so you have <picture
@equivalent="equivalent content"> or <figure><picture equal="equivalent
content">pics.png<picture><figure> etc. However, is this vastly
different from what we have already, (in a sense)? Using a multi-valued
'equivalent' attribute certainly has advantages for authors, as its
format and practical use could be made to be similar for each element
depending on the element being ascribed the equivalent content - so that
is a plus. I guess though as Al pointed out there are potential problems
under the hood a la:

> One drawback of a multi-valued "equivalent" attribute is that the equivalent
> relationship is symmetrical,[...] This is fragile code; many
> if not most instances of this would contain inconsistent data. 

I am not sure of many of the subtleties and potential technical problem
areas (which no doubt may be obvious to many others on this list) but I
think the idea of an @equivalent attribute has potential. If at the very
least it has a positive connotation and implies to the author that they
must treat its application seriously as for many people with
disabilities, it *is* the content.

Josh

[1] http://www.w3.org/html/wg/html5/diff/#absent-attributes
[2] http://www.whatwg.org/specs/web-apps/current-work/#video

Received on Tuesday, 17 July 2007 22:34:41 UTC