- From: Steve Faulkner <faulkner.steve@gmail.com>
- Date: Wed, 14 Mar 2012 15:14:45 +0000
- To: John Foliot <john@foliot.ca>
- Cc: Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>, Silvia Pfeiffer <silviapfeiffer1@gmail.com>, Charles McCathieNevile <chaals@opera.com>, RichardSchwerdtfeger <schwer@us.ibm.com>, W3C WAI-XTECH <wai-xtech@w3.org>, HTMLAccessibility Task Force <public-html-a11y@w3.org>
- Message-ID: <CA+ri+Vn0=8BnN8cFsKyQCNV0jhbgM3xQPx_KNw2GjJveEsq86g@mail.gmail.com>
Hi John, >I think you are mistaken here (and FWIW I checked this with Rich). I am checking with rich will get back to you on his reply, example of brokenness: IE's implementation breaks when an accessible description on an image is provided using aria-describedby >In all working example of @longdesc today (whether via a screen reader or 3rd-party browser extension) they all operate by querying the DOM, which IMHO is >not actually "broken or poorly thought out" - in fact it simply underscores that any HTML consuming tool *could* do something useful with @longdesc, they >simply choose not to. If tools are querying the DOM they can just access the longdesc directly, IE'simplementation does not help with that in any way, all it does i pollute the accessible description. If IE wanted to fudge it they could pass the longdesc value to the acc value property perhaps. best regards Steve On 14 March 2012 14:42, John Foliot <john@foliot.ca> wrote: > Quoting Steve Faulkner <faulkner.steve@gmail.com>: > > the bug is in the IE implementation >> acc description is for a human readable description not to pass URL's >> >> the implementation is broken and poorly thought out. >> > > Hi Steve, > > I think you are mistaken here (and FWIW I checked this with Rich). > > At issue is the AAPI (and now ARIA) processing of non-visible content. > The ARIA Implementation Guide states: > > "The following elements are not exposed via the accessibility API and > user agents MUST NOT include them in the accessibility tree: ...Elements, > including their descendents, that have host language semantics specifying > that the element is hidden, such as CSS display:none or visibility:hidden > or HTML 5 hidden attribute." > - http://www.w3.org/WAI/PF/aria-**implementation/#exclude_**elements<http://www.w3.org/WAI/PF/aria-implementation/#exclude_elements> > > Since active links (and other Semantic structure) should normally be > exposed to the Accessibility Tree, but hidden content NOT exposed, the URL > for the longer description that @longdesc references (ROLE_SYSTEM_LINK) > must not be conveyed, thus it defaults to AccDescription (which is string > text): > > "The text alternative for a given node is computed as follows: Skip > hidden elements unless the author specifies to use them via an > aria-labelledby or aria-describedby being used in the current computation. > By default, users of assistive technologies won't receive the hidden > information, but an author will be able to explicitly override that and > include the hidden text alternative as part of the *label string* sent to > the accessibility API." (emphasis mine) > - http://www.w3.org/WAI/PF/aria-**implementation/#mapping_**additional_nd<http://www.w3.org/WAI/PF/aria-implementation/#mapping_additional_nd> > > IE is actually getting it right! > > In all working example of @longdesc today (whether via a screen reader or > 3rd-party browser extension) they all operate by querying the DOM, which > IMHO is not actually "broken or poorly thought out" - in fact it simply > underscores that any HTML consuming tool *could* do something useful with > @longdesc, they simply choose not to. > > JF > > -- with regards Steve Faulkner Technical Director - TPG www.paciellogroup.com | www.HTML5accessibility.com | www.twitter.com/stevefaulkner HTML5: Techniques for providing useful text alternatives - dev.w3.org/html5/alt-techniques/ Web Accessibility Toolbar - www.paciellogroup.com/resources/wat-ie-about.html
Received on Wednesday, 14 March 2012 15:15:39 UTC