I don't know if you've seen the recent Accessible Rich Internet
Applications <http://www.w3.org/TR/wai-aria/> draft? (There's also a
primer at <http://www.w3.org/TR/wai-aria-primer/>.) It describes a
number of standard states that can be added to custom controls.
Rather than potentially fitting multiple values into a reldata
attribute, it defines a host of attributes beginning with "aria-".
Example:
<span role="checkbox" aria-checked="true">Foo</span>
I believe a number of script libraries (Dojo for example) plan on
supporting ARIA. Firefox has some ARIA support already.
Thanks for pointing to WAI-ARIA. Just to clarify the status, both Dojo's
Dijit library and Firefox 3 fully supports the current draft on both
Windows and Linux. There are still being tweaks made in screen readers
to support the outer edges of the ARIA widget semantics as well as ARIA
live regions (for areas of the page that change but are not really
widgets, such as an updating scoreboard).
More info on who is working on ARIA support in the FAQ here:
http://developer.mozilla.org/en/docs/ARIA:_Accessible_Rich_Internet_Applications/Relationship_to_HTML_FAQ#Who_supports_ARIA.3F
- Aaron
The current HTML 5 draft doesn't mention ARIA anywhere. Perhaps it
should clarify the relationship (or non-relationship as it is at
present), even if it's only a brief mention in section 1.1.
Regards,
Dave