Re: use of aria-hidden to provide a text description not visible on the page.

Hi Leif,
>Many ARIA supporting ATs doesn't actually seem to support this. :-(

i don't think this is a correct statement.
>Jaws11+Firefox3.6.9 is a quite common AT: It supports aria-labelledby.
>But fails to expose (to users) labels that have been hidden with CSS
>display:none or visibility:hidden.

worked for me for both aria-describedby and aria-labelledby referencing a
div hidden using CSS display:none


> And Jaws+IE7 at least isn't any better.
and so it shouldn't be since IE7 does not implement ARIA support.

regards
Stevef


On 11 September 2010 11:09, Leif Halvard Silli <
xn--mlform-iua@xn--mlform-iua.no> wrote:

> James Craig, Fri, 10 Sep 2010:
> >> "That's correct. The label of visible elements should still be
> >> exposed to accessibility APIs (as a computed string), even if the
> >> labeling element (that contained all or some of that string) is
> >> hidden."
>
> Many ARIA supporting ATs doesn't actually seem to support this. :-(
> See below.
>
> James Craig, Fri, 10 Sep 2010 12:25:01 -0700:
> > The spec recommends authors always SHOULD update the value of
> > aria-hidden, but in practice, when using visibility:hidden or
> > display:none it's rarely needed since all popular screen readers rely
> > on rendering engine support. Less common AT that is not supported by
> > a rendering engine (I think only FireVox, atm) relies on the DOM
> > being updated correctly, too.
>
> Aria-hidden="true" is probably most useful as a progressive enhancement
> feature for those AT that supports it. Example:
>
> Jaws11+Firefox3.6.9 is a quite common AT: It supports aria-labelledby.
> But fails to expose (to users) labels that have been hidden with CSS
> display:none or visibility:hidden. And Jaws+IE7 at least isn't any
> better.
>
> VoiceOver respects aria-hidden regardless of whether the element is
> actually hidden (via CSS), whereas Jaws+Firefox and NVDA+Firefox seems
> to fail to give any regard to aria-hidden whatsoever.
>
> Since common AT do not expose hidden labels, it might be best to, for
> maximum compatibility, to hide labels via other means, such as
> off-screen positioning. However, this could cause AT to present labels
> twice. But by setting such labels to aria-hidden="true", one can at
> least make sure that supporting AT, such as VoiceOver, does not read
> the labels twice.
> --
> leif halvard silli
>



-- 
with regards

Steve Faulkner
Technical Director - TPG Europe
Director - Web Accessibility Tools Consortium

www.paciellogroup.com | www.wat-c.org
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