23.04.2015, 23:01, "Michael Gower" <michael.gower@ca.ibm.com>:
I have been wondering about a related phenomenon I'm seeing in content management systems where an article, blog post or whatever may or may not be presented inside a larger page which already has heading mark-up. In the first instance, I may bring up a blog post in its own window, and the headings assigned by the author (assuming they've done them right) will properly convey the structure to me as H1, H2, H2, H3, etc
But in the second instance, that blog post is presented inside a larger portal, and I may suddenly find my H1 is now nested inside an H3.
I'm wondering if this may be solved with HTML5 sections, where each section becomes a subsection of the controlling document.
In theory it could - but the theory turned out not to work in practice, so far.
I would think a relative heading structure of the same kind might be useful when one ran out of heading levels in a contiguous document. Whether you decided to start again at level 6 (e.g., 6.1, 6.2, 6.3) or made your sections at a higher level, is this a potential solution? And if so, what considerations are there for how users and assistive technologies which identify and orient themselves with such relative heading levels?
A tool that lets you embed a piece of content into another should (according to [ATAG]) maintain accessibility - in this case, re-work the heading structure.
i.e. your h1 in the above example would be converted to h4, your h3s would become h6, and your h5s would become h6 with aria-level="8"…
The outline algorithm is perhaps interesting for navigation in browsers - if we ever get another browser with navigation that is better than "tab through everything" - but alongside screenreaders it is also very useful for authoring software.
[ATAG] e.g. http://www.w3.org/TR/ATAG/atag10.html#check-leave-access-content …

Michael Gower
Senior Consultant

IBM Accessibility

1803 Douglas Street, Victoria, BC  V8T 5C3
voice: (250) 220-1146 * cel: (250) 661-0098 *  fax: (250) 220-8034

From:        "Siegman, Tzviya - Hoboken" <tsiegman@wiley.com>
To:        Mitchell Evan <mtchllvn@gmail.com>, Wayne Dick <waynedick@knowbility.org>
Cc:        "w3c-wai-ig@w3.org" <w3c-wai-ig@w3.org>
Date:        04/23/2015 12:41 PM
Subject:        RE: deeply nested headings

There more likely scenarios is a long embedded article or aside with its own internal headings.
This is an EPUB issue, but I can attest that EPUB creators have the question (myself included). This question is relevant for HTML that does not go into the EPUB format as well.
Thanks for your help.
Tzviya Siegman
Digital Book Standards & Capabilities Lead
From: Mitchell Evan [mailto:mtchllvn@gmail.com]
Thursday, April 23, 2015 12:15 PM
Wayne Dick; Siegman, Tzviya - Hoboken
Re: deeply nested headings


I'll rephrase the question two ways.

First, what's a good experience for the user? To answer this, I'd like to hear about real-world examples. Are we talking about a homogeneous hierarchy, from chapters all the way down to sub-sub-sub-sub-sub-headings? Or are there sometimes distinct regions of content, like a long embedded article with its own internal headings? The harder problem to solve will be cognitive load for anybody, trying to keep track of this much depth.

Second, what is technically correct for HTML, supported today, and reasonably future-proof? It's a valid question, which I'll leave others to answer.
On Thu, Apr 23, 2015 at 8:35 AM Wayne Dick <waynedick@knowbility.org> wrote:
I think the role with new level is interesting, but a misuse of ARIA.  The problem is with the scope of HTML.  This is probably an ePUB issue.  Publication and testing need more robust semantics than HTML has to offer.

Charles McCathie Nevile - web standards - CTO Office, Yandex
chaals@yandex-team.ru - - - Find more at http://yandex.com