W3C home > Mailing lists > Public > public-html@w3.org > July 2007

Re: Opening thoughts on WAI-ARIA in HTML5

From: Robert Burns <rob@robburns.com>
Date: Thu, 19 Jul 2007 18:59:40 -0500
Message-Id: <5A33CC24-EABC-459C-ACD2-746A1C075EA4@robburns.com>
Cc: Al Gilman <Alfred.S.Gilman@IEEE.org>, public-html@w3.org
To: joshue.oconnor@cfit.ie


On Jul 19, 2007, at 4:31 PM, Joshue O Connor wrote:
> If [legacy HTML4 accessibility  features]  are supported - and the  
> spec also supports 'Backward
> compatibility to ARIA, including the role attribute' then that is one
> powerful spec - when combined with improved, easy to author, vendor
> supported, accessibility features. The spec will then both look  
> forward
> and back. Maybe we should call this the Janus project?

I agree. We have a great opportunity to get accessibility right with  
HTML5: or improve it drastically anyway.

>>> + A preference for access to accessibility information via the DOM
>
> While this in not a HTML WG issue it is still relevant: This would be
> ideal - in particular for dynamic content - and it is stated here as a
> preference.

I think this is an HTML WG issue. After all we are specifying a DOM  
for HTML5 including UA conformance criteria. One of the problems  
faced by screen readers and aural browser extensions or aural  
browsers using general purpose rendering engines (as I understand it)  
is that sometimes these engines toss out non-visual portions of the  
DOM. There's no way for extensions to make use of the DOM for aural  
CSS properties because they're left on the cutting room floor (so to  
speak). Similar problems could arise for the scope/header algorithm;  
or for accessing @longdesc  or accessing the contents of an XML <img>  
element. Just because something is not rendered visually does not  
mean we cannot provide UA guidance on retaining this information. If  
its available in from the general UA engines, it can be used by  
screen readers and  other SDK derived software.

> Many screen readers continue to use the Off Screen Model
> (OSM). Is it foreseen that most future iterations of screen readers  
> will
> interrogate the DOM directly and not use the OSM? This is probably
> likely. AFAIK Dolphins' Supernova is the only screen reader that
> currently does this. Has the WG contacted any vendors like GW Micro  
> and
> Freedom Scientific etc to see that they support this shift towards
> access to accessibility information via the DOM by changing the way
> their products work?

I think this would be an important place for some evangelism  from  
our WG. I would add Apple to your list (with VoiceOver) too as Apple  
has a good measure of control over both the screen reader and the web  
SDK. I'm not sure if the problem with these screen reader vendors is  
a lack of awareness, or whether their users have expressed an  
indifference to HTML and CSS specific accessibility features or  
whether performance optimizations end up tossing out crucial DOM  
accessibility information. It's a mystery.

Take care,
Rob
Received on Thursday, 19 July 2007 23:59:48 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Wednesday, 9 May 2012 00:16:02 GMT