Re: Handling of landmark roles on native markup

Hi Aaron,
I would also point out that adoption of this behaviour would result in a
need to lodify the HTML5 conformance rules, which are currently predicated
on ARIA roles always overriding native semantics.

While not a reason not to make the change, it is a factor that needs to be
taken into account in the introduction of the changes. As getting ANY
changes in to HTML5 is not a trivial task.

regards
steve

On 16 March 2012 18:24, Aaron Leventhal - Code <aaronlevbugs@gmail.com>wrote:

> I recently discovered that Firefox and WebKit-based browsers handle
> landmarks differently.
>
> WebKit implements the current ARIA implementation guide at
> http://www.w3.org/TR/wai-aria-implementation/#mapping_role --
> "For the standard role mechanism of the accessibility API, the user agent
> *MUST* use the first token in the sequence of tokens in the role attribute<http://www.w3.org/TR/wai-aria-implementation/#def_attribute>
>  value <http://www.w3.org/TR/wai-aria-implementation/#def_value> which
> matches, on comparison, the name of any non-abstract WAI-ARIA role."
>
> Firefox/Gecko implements an older version of the implementation guide at
> http://www.w3.org/TR/2009/WD-wai-aria-implementation-20090224/#mapping_role
> "The first role token with a known mapping to accessibility APIs SHOULD be
> used when mapping to the accessibility API via the standard role mechanism
> of the accessibility API. Use the role table below and apply any special
> case rules that are specified."
>
> As I see it, there are two advantages to the older system:
> 1. The landmark role can complement native semantics without clobbering
> them, e.g.
>  <input type="text" role="search">
>  <table role="complementary">
>  <ul role="navigation">
> 2. It enables forward compatibility of ARIA-enabled content with future
> browsers and platforms, as fallback roles can be used. For example, <table
> role="calendar grid"> allows newer platforms who understand a "calendar"
> role to map directly to that, but previous versions which did not know
> about "calendar", would fall back on "grid", still a valid, usable role.
>
> I'd like to help sync the browser implementations on this issue. My
> (opinion) is that the older role processing is better for the reasons given
> above. I would love to hear other opinions.
>
> Thanks as always,
> Aaron
>
>


-- 
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