Re: Comment on WAI-ARIA Role: Needs "hint" Role

Rich Schwerdtfeger
Distinguished Engineer, SWG Accessibility Architect/Strategist
blog: http://www.ibm.com/developerworks/blogs/page/schwer

Doug Schepers <schepers@w3.org> wrote on 09/04/2008 05:40:34 PM:

> Hi, Rich-
>
> Richard Schwerdtfeger wrote (on 9/4/08 5:26 PM):
> >
> >> > Information on how to interact with an object would use the
> >> description role.
> >>
> >> No, that's a misuse of the "description" role.  A "description" should
> >> be suitable as a textual replacement for the image, in case the image
in
> >> not available or perceivable.
> >
> > That is not how we designed it. Description is designed to replace
> > longdesc, provide additional help information, and
> > link to prose on the page if necessary.
>
> Everything I've read about "longdesc" matches the use I described above:
>
> * http://www.w3.org/TR/REC-html40/struct/objects.html#adef-longdesc-IMG
> * http://www.w3.org/TR/WCAG10-HTML-TECHS/#long-descriptions
>
> Maybe there's some subtle point I'm missing.  Are you saying that
> "description" should or should not provide "hint" information?  I
> contend that it should not.
>

Not if it is going to describe an action performed by an input event - no.

>
> > I see. The problem with that is the platform accessibility API have no
> > single hint. Looks like you modeled hint
> > after XForms or perhaps the other way around.
>
> I suspect you're right that the <hint> element planned for SVG 1.2 Full
> was informed by XForms, and in turn informed our desire to use a role
> instead of an element for that purpose.
>
> It seems a useful distinction to me... am I wrong here?
>
A hint is an attribute of an object even though you are using xml elements
to represent it.
>
>
> The one problem I see is that with script you could
> > potentially have multiple actions and consequently multiple "hints" -
> > one corresponding to each action. Have you
> > thought about this for SVG or do you always expect there to be one
action?
>
> It would be up to the author to make judicious use of hints.  We aim to
> provide the infrastructure to enable them to do so in a structured and
> well-defined way.  Having a "hint" role defined in ARIA is the logical
> way to effect that.
>
again - this is not a role. you can' visibly see or operate a hint.

>
> > We do have, in some accessibility api, is an action description which
in
> > effect would be your "hint."
>
> Ok, that seems like a place to start... how would this relate to what's
> specified in ARIA?  Will there be a role attribute value for "action"?
> Otherwise, where would the action description be placed?
>
Not this go around. So this is a plus for SVG.
>
> > So, for SVG there should not be an overlap. We relegate desrcliption to
> > "A brown horse, blah blah."
> > ARIA, consequently has no equivalent for hint so for SVG the mapping
> > should be to the corresponding action. This is typically short though.
> >
> > Make sense?
>
> Actually, not really.  What do you mean by, "the mapping should be to
> the corresponding action"?  In what way?  What form would the
> information about the "corresponding action" take?  How will it be
> exposed to the UA or user?  Is this a text description, as I described,
> or is it somehow inferred from key mappings, script listeners, etc.?
>
> Maybe you could provide an example, to clarify?
>
The browser would have an action API for each action you could say have on
a button. Associated
with that action would be it's action name which you would load with the
hint. Action would be a binding
between the key mapping and the corresponding function (could be script).

>
> > We can clarify this in our spec that description should not be used to
> > describe an action.
>
> That sounds good, but this seems to potentially conflict with how you
> defined the "description" role above.
>
As I said, we can provide more detail to say that describedby is not for
describing an
action to be performed. ... or something to that order. It would be rather
more detaild information
about the object.

> Regards-
> -Doug Schepers
> W3C Team Contact, WebApps, SVG, and CDF