Re: aria-activedescendant changes to the aria-implementation guide

Hi David,

You wrote:
> The fact "there is no reliable mechanism to notify" a web
> "application" that the aria-activedescendant has changed is not enough
> of a reason to further complicate ARIA for authors ...

I don't see how it complicates things for authors.  There being no way
to be aware of changes is quite liberating.  It means that authors need
not (can't?) look for them.  Nothing for authors to do here.  And, it's
likely they don't bother looking anyway.  Didn't you point that out 100
years ago? :-)

>  ... and browser implementations.

I have no opinion here (well, not much of one), and defer to you.

I gather your suggestion is to recommend that authors not use
aria-activedescendant, ever?  Could that be tempered to:  don't use
aria-activedescendant until such time as there is a way to notify
scripts of externally made changes.  There being "no reliable mechanism
to notify a web application of changes" is the crux of the problem, and
it's larger than just aria-activedescendant.

Somewhat related:  the spec says [1]:

> When a web application maintains a local representation of
> accessibility information through WAI-ARIA roles, states, and
> properties, the user agent MUST provide a method to notify the web
> application when a change occurs to any of the related states or
> properties in the system accessibility API.

It goes on to suggest that "... Many state and properties can be changed
by assistive technologies through existing accessibility APIs by
responding to a default action event."  Would that work here for
aria-activedescendant, without being overly complicated?  Using a
checkbox as an example, the user agent wouldn't directly modify a that
checkbox's aria-checked value.  It would instead tell the checkbox to do
its default action, which would lead to the associated script
"naturally" updating checkbox's aria-checked state.

> Joseph, remember talking about this 100 years ago ;)

Ah memories.  The good 'ol days. ;-)


[1] http://www.w3.org/WAI/PF/aria/conformance#ua_domchanges

-- 
;;;;joseph

'I had some dreams, they were clowns in my coffee. Clowns in my coffee.'
                     - C. Simon (misheard lyric) -

Received on Thursday, 28 April 2011 17:07:36 UTC