- From: Edward O'Connor <eoconnor@apple.com>
- Date: Tue, 11 Sep 2012 16:52:40 -0700
- To: public-html@w3.org
- Cc:
Hi all, On Monday I posted about our proposed new text to address problems identified with the text adopted by the WG in the ISSUE-204 decision.[1] Here is a small revision of that text which attempts to address several of the concerns that have been raised in Bugzilla[2] and here on public-html: > Accessibility APIs are encouraged to allow a way to expose structured > content while marking it as hidden in the default view. Such content > should not be perceivable to users in the normal document flow in any > modality, whether using Assistive Technology or mainstream User > Agents. > > When such features are available, User Agents may thus expose the full > semantics of hidden="" elements to Assistive Technology when > appropriate, if such content is referenced indirectly by an ID > reference or hash-name reference. This allows Assistive Technologies > to access the content structure upon user request, while keeping the > content hidden in all presentations of the normal document flow. Some > examples of where it would be appropriate for the structure of > hidden="" elements to be exposed to users of AT with such an API > include: > > * a <map> referenced from <img usemap> > * table headers referenced with the headers="" attribute > > Cases where it would be inappropriate for the structure of hidden="" > elements to be exposed to users of AT with such an API include: > > * a hidden="" element referenced by <a href> within the same document > * a hidden="" form element referenced by <label for> > Note: The sorts of elements referenced from <label for> cannot be > flattened without losing essential meaning (see below). > > Other specifications which define elements and attributes which may be > included in valid HTML documents (such as SVG, MathML, and WAI-ARIA) > may define how or whether this applies to their elements and > attributes. > > Because historically some User Agents have flattened hidden content > when exposing such content to Assistive Technology, authors SHOULD NOT > reference hidden="" content which would lose essential meaning when > flattened. Changes (with rationale) described below. Leif wrote, in [3]: > Summarized, we could say that Ted’s new text recommends that, in case > of indirect relations between hidden *labels/captions* and some > visible content then the hidden label/caption content should be > exposed. Whereas when visible label/caption content reference hidden > *content*, then the hidden content should not be exposed. Could a > summary along those lines be added to the text? I'm not sure that accurately captures the principle at heart, but I've tried to rework the text a bit to make it more clear. > (3) I think the text > """Cases where it would be inappropriate include""" > should be congruent with the text about when it *would be* approriate. > For example like this: > """Cases where it would be inappropriate for the structure > of hidden="" elements to be exposed to users of AT with > such an API include""" Done. > (4) Regarding the negative examples, then they should be described > more congruently with the positive examples. Done. John constructed an example in [4] which used <td headers> to point at a <th hidden> containing an <a> element. I think this wouldn't be conforming, due to the language stating that "authors SHOULD NOT reference hidden content which would lose essential meaning when flattened." But I had apparently failed to preserve that sentence in the new text. Sorry about that! Fixed. John wrote: > 1) If the emergent spec is prepared to provide an itemized list of > what semantic constructs can be exposed (and thus are conformant, such > as <span> or <th>) versus those that are not (such as a hidden <a> > element) - i.e, something more definitive than "Cases where it would > be inappropriate include..." then I think that might be one path > forward. As Maciej pointed out in [5], "generating a complete and correct list would take considerable time." Given that the original ISSUE-204 text only had one example and not an exhaustive list, I think we can improve the text now and add a comprehensive list later, in a followup bug. > 2) The other is to specifically mandate User Agents that when an <a> > element is referenced, that is normally "hidden", that the UA > subsequently present that link visually for those users that so need. This sounds interesting. Do you have a suggestion for how to word such a mandate? I think we might be able to come up with something you and I can both live with. > As one of those who "FOed" this proposal, I have now tried to offer 2 > potential solutions to address the concerns I have. Thanks! :) I really appreciate everyone trying to work the remaining technical issues here. I'm pretty happy with the above text. It could be made better, but I think it's so much better than what's in the spec that I'd rather go with this now & address further tweaking in followup bugs. Given that, * Does anyone object to proceeding with the above version of the text? * Alternately, do you support going with this for now & filing followup bugs for further refinement? Thanks, Ted 1. http://lists.w3.org/Archives/Public/public-html/2012Sep/0141.html 2. https://www.w3.org/Bugs/Public/show_bug.cgi?id=18744 3. https://www.w3.org/Bugs/Public/show_bug.cgi?id=18744#c14 4. http://lists.w3.org/Archives/Public/public-html/2012Sep/0146.html 5. http://lists.w3.org/Archives/Public/public-html/2012Sep/0148.html
Received on Tuesday, 11 September 2012 23:53:08 UTC