- From: Laura Carlson <laura.lee.carlson@gmail.com>
- Date: Thu, 15 Jul 2010 06:42:52 -0500
- To: Steven Faulkner <faulkner.steve@gmail.com>, Maciej Stachowiak <mjs@apple.com>, Sam Ruby <rubys@intertwingly.net>, Paul Cotton <Paul.Cotton@microsoft.com>
- Cc: HTML Accessibility Task Force <public-html-a11y@w3.org>
Hi Steve and all, Thank you very much for providing rationale for role="presentation". I updated the change proposal to include it. http://www.w3.org/html/wg/wiki/ChangeProposals/ImgElement20090126#role.3D.22presentation.22_Attribute Maciej, please re-add this change proposal to the change proposal table for HTML ISSUE-31. Thanks. Best Regards, Laura On 7/15/10, Steven Faulkner <faulkner.steve@gmail.com> wrote: > Hi Laura, > > role=presentaion can be placed on any element to indicate that it should not > be included in the accessible tree by the browser. > It is intended that user agents do not expose the element role via > accessibility APIs when role="presentation" is present on an element. > > In HTML5 as per the current spec alt="" [1] on an image has an implied ARIA > role of presentation, although current implementations do not honour this. > use alt="" does not result in the img being removed from the accessible tree > by browsers. AT recognise alt="" as indicating that the image can be safely > hidden from the user, but their ways of handling this are not uniform. > So in the spec role="presentation and alt="" are equivalent. Allowing > role="presentation" to be a conforming replacement for alt="" just > recognises what the spec states. > > Why allow role="presentation" to act as an alternative to alt=""? > it is specified and implemented to do what alt="" is specified to do. > It is non specific, it works on all elements. > As per the rules specified in current spec pertaining to its use [1] the > use of role="presentation" is not dis-allowed on the img element it is in > fact stated that it is the only role that can be applied to an img that has > an alt="", so you can do this: > > <img role="presentation" alt=""> > > and nowwhere in the aria section [1] does it state you can't do this: > > <img role="presentation"> > > but it will result in a conformance error, which appears both incongruous > and illogical. > > > [1] > http://dev.w3.org/html5/spec/content-models.html#annotations-for-assistive-technology-products-aria > > -- > 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 -- Laura L. Carlson
Received on Thursday, 15 July 2010 11:43:23 UTC