- From: Steven Faulkner <faulkner.steve@gmail.com>
- Date: Mon, 17 Aug 2009 11:02:16 +0100
- To: Maciej Stachowiak <mjs@apple.com>
- Cc: Benjamin Hawkes-Lewis <bhawkeslewis@googlemail.com>, Ian Hickson <ian@hixie.ch>, HTMLWG WG <public-html@w3.org>, W3C WAI-XTECH <wai-xtech@w3.org>
- Message-ID: <55687cf80908170302j4331a3aap7cf664d62ca94109@mail.gmail.com>
hi all, i think the following examples should raise a conformance error. <a href="#"><img src="delete.png" role="presentation"></a> <a href="#"><img src="delete.png"></a> <a href="#"><img src="delete.png" alt=""></a> <a href="#"><img src="delete.png" role="presentation" aria-labelledby="this"></a> <span id="this">delete</span> <a href="#"><img src="delete.png" alt="" aria-labelledby="this"></a> <span id="this">delete</span> i think the follwoing should not <a href="#"><img src="delete.png" aria-labelledby="this"></a> <span id="this">delete</span> regards stevef 2009/8/17 Maciej Stachowiak <mjs@apple.com> > > On Aug 17, 2009, at 2:00 AM, Benjamin Hawkes-Lewis wrote: > > On 17/08/2009 09:42, Maciej Stachowiak wrote: >> >>> Would it be appropriate, in light of this, to add a user agent >>> requirement that an img with empty alt should not be mapped to >>> accessibility APIs at all? >>> >> >> Given the variety of authoring practice around "alt", I don't think that >> would be safe. >> >> In situations like: >> >> <a href="#"><img src="delete.png" alt=""></a> >> >> It's useful to AT for the "img" to be exposed and to be able to access >> "src" attributes for the purpose of providing a substitute for proper >> alternative text. >> > > If that's so, then wouldn't it be better for authors to use alt="" instead > of role="presentation", so that AT can decide whether it needs to expose the > image anyway? In particular, if your example was marked up like this: > > <a href="#"><img src="delete.png" role="presentation"></a> > > Then isn't it equally necessary and appropriate for AT to expose that > image? > > It seems like, based on this example, images should always be exposed to > accessibility APIs, and AT should make the call on whether it needs to > override the author-provided semantics. > > http://www.w3.org/TR/WAI-USERAGENT/guidelines.html#tech-missing-alt >> >> More tendentiously, perhaps, in situations like: >> >> <p>As you can see from the chart below, sales increased in 2008:</p> >> <img alt="" src="chart.png"> >> >> Even if users can't consume the chart themselves, it's useful to users to >> be able to download or hotlink that referenced chart in a collaborative >> environment (e.g. a corporate wiki). >> >> By contrast: >> >> <img alt="" src="bullet.png"> >> >> really is purely decorative; in a collaborative environment that seems >> likely to be generated by authoring software. >> > > And likewise for these examples - it seems like AT should be left free to > apply heuristics. > > Regards, > Maciej > > > -- with regards Steve Faulkner Technical Director - TPG Europe Director - Web Accessibility Tools Consortium www.paciellogroup.com | www.wat-c.org Web Accessibility Toolbar - http://www.paciellogroup.com/resources/wat-ie-about.html
Received on Monday, 17 August 2009 10:02:59 UTC