- From: Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>
- Date: Sun, 29 Jan 2012 23:30:35 +0100
- To: Matthew Turvey <mcturvey@gmail.com>
- Cc: John Foliot <john@foliot.ca>, Silvia Pfeiffer <silviapfeiffer1@gmail.com>, Laura Carlson <laura.lee.carlson@gmail.com>, Sam Ruby <rubys@intertwingly.net>, Paul Cotton <Paul.Cotton@microsoft.com>, Maciej Stachowiak <mjs@apple.com>, HTML WG <public-html@w3.org>
Matthew Turvey, Sun, 29 Jan 2012 18:15:35 +0000: > On 28 January 2012 04:57, John Foliot <john@foliot.ca> wrote: >> Matthew Turvey wrote: > Since this change to the HTML5 spec seems to be just bringing it into > line with what is already specified in ARIA, Whether it should be *conforming* to point to sections that are hidden with the @hidden attribute, has nothing - in itself - to do with ARIA. That it *works* - per ARIA - to point to hidden sections - regardless of how they are hidden - is the only link to ARIA here, as far as I can see. > It seems there are parts of WAI-ARIA 1.0 where no one can agree on > what it actually specifies, or whether what it does apparently specify > is actually possible or even desirable. Which are the sections of ARIA 1.0 that you have in mind? > This simple solution meets all the requirements: > > <a href=foo><img src=pic alt="*the purpose of the link*"></a> Most or all AT present the above as a link and not as an image. > If users need to be able to determine programmatically that the link > is a long description of the image, or authors want to put two links > on one image: > > <a href=foo rel=longdesc><img src=pic alt="*a programmatically > determinable long description link*"></a> No UA/AT support rel=longdesc. Hence: same problems as described above. > <img src=pic alt="*text alternative*" usemap=#map> > <map name=map> > <area shape=rect coords=0,0,100,50 href=foo rel=longdesc alt="*a > programmatically determinable long description link*"> > <area shape=rect coords=0,50,100,100 href=bar alt="*on an image that > is already a link*"> > </map> In Safari+VoiceOver, the @alt text of the <img> in this image map, is not presented to the user at all. Only the alt text of the <area> elements is presented. Last I checked, there were similar problems in other AT as well. > This universal design approach works for everyone, right now, Given what I described above, I fail to see how img@longdesc can currently be replicated with your above mentioned techniques. > and > doesn’t require changes to accessibility APIs, software upgrades, > browser add-ons, user training, author training, or employing the > services of an accessibility specialist. Unlike longdesc (and ARIA) > this technique currently works in all screen readers, including > VoiceOver, Orca and NVDA, as well as all other AT, including screen > magnifiers, and all browsers. Doesn't match the terrain - see my note above Safari+VoiceOver. There seems to be a general problem related to handling something as both a link and an image. And likewise, when something is considered an image, then the element is seen as being empty, even if it - such as for <object data=image> Text. </object> - is non-empty. The only solution that has solved that problem, so far, is @longdesc. In a summary: If UAs/ATs supported rel=longdesc ... If UAs/ATs would present the alt text of <img usemap=m alt=imageText > If UAs/ATs would present fallback content of <object type=image/png> … ... then we could have used those methods for presenting a link to a long description. None of the above has any thing to do with ARIA. > Since nearly everyone agrees we should include ARIA support in HTML5, > it makes sense to include the ARIA functionality the authors of > WAI-ARIA 1.0 clearly believe is essential for AT users, and improve > existing accessibility APIs as required to support that functionality > as Silvia previously suggested, and/or patch it in at the UA level as > Jonas has previously demonstrated with his proof-of-concept code to > make Firefox expose a link pointed to with aria-describedby. It would be nice if @aria-describedby could point to a section *without* flattening the content, semantically. Then we could, for example, do a thing like this: <object aria-describedby=fallback data=image id=fallback > <i>Image description</i> <a href=link>Long description</a> </object> But unfortunately, this does not work. -- Leif Halvard Silli
Received on Sunday, 29 January 2012 22:31:19 UTC