- From: Richard Schwerdtfeger <schwer@us.ibm.com>
- Date: Mon, 25 Aug 2008 10:43:52 -0500
- To: Doug Schepers <schepers@w3.org>
- Cc: public-pfwg-comments@w3.org, public-pfwg-comments-request@w3.org, www-svg <www-svg@w3.org>
- Message-ID: <OF344DB405.976C0F8B-ON862574B0.00559461-862574B0.005669AD@us.ibm.com>
response below. Rich Schwerdtfeger Distinguished Engineer, SWG Accessibility Architect/Strategist Chair, IBM Accessibility Architecture Review Board blog: http://www.ibm.com/developerworks/blogs/page/schwer public-pfwg-comments-request@w3.org wrote on 08/22/2008 04:58:45 PM: > > Hi, ARIA folks- > > The SVG WG is discussing the use of a few specific roles for SVG > elements, 'title' and 'desc'. We think it would be very useful and > appropriate to allow the role values 'description' and 'tooltip' (among > others) on those elements. However, both of those role values require that: > [[ > Objects with this role must be referenced through the use of a > describedby. > ]] > > In SVG, we are defining an algorithm that describes the relationship > between the 'title' or 'desc' element and the element or elements they > are describing, based on a parent-child (or more precisely, > container-contained) relationship. Basically, for most uses, the > 'title' and 'desc' elements describe their parent element (which may in > turn simply be a group of elements, in which case the general > description applies to the collection of child elements). > > Therefore, the 'describedby' role value is superfluous and possibly > contradictory to the well-structured solution of SVG; similarly, it is > redundant with the HTML 'label' element, with its 'for' attribute. For > both these cases, the 'describedby' role may (and should) be inferred by > the UA. > Doug, describedy is not a role. It is an attribute that references the description. label and description are entirely different. Label is a short visible label to an object. As long as the SVG author sticks to the hierarchical structure of SVG to associate the description (there is a role of description) then for SVG there should be no need to have to use the describedby relationship and the UA can map the information to the platform accessibility API. However, should the author provide a description in prose elsewhere in SVG this is where you would want to use describedby. If we are mandating somehting already provided in the host language I would agree with you - "should" makes sense. > Further, requiring this reference may discourage use of roles in these > circumstances, by introducing arbitrary and unnecessary extra work on > the part of the author. > > Therefore, our suggestion is that you remove this mandatory stricture, > or soften it to a SHOULD or MAY, or describe a way in which a language > may describe an implicit value for the 'describedby' role based on the > host language's semantics. You do allude to this last option in > WAI-ARIA: [1] > Please point to the section of the specification you are referring to as you are mixing roles and role attributes. > [[ > Build relationships > > ... > > Some relationships are determined automatically from the host language, > such as by using the label tag in HTML. > ]] > > However, you don't seem to describe the manner in which a language > defines this, and the MUST statement in the roles seems to contradict > the "Build relationships" wording. > > > [1] http://www.w3.org/TR/wai-aria/#buildingaccessibleapplications > > Regards- > -Doug Schepers > W3C Team Contact, WebApps, SVG, and CDF >
Received on Monday, 25 August 2008 15:44:45 UTC