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From: Cameron McCormack <cam@mcc.id.au>
Date: Tue, 21 Oct 2008 22:38:31 +1100
To: public-svg-wg@w3.org
Message-ID: <20081021113831.GA16336@arc.mcc.id.au>

Hello WG.

In the description of the @role attribute in the Structure chapter it
currently says:

  Unlike the 'class' attribute, 'role' attribute values are intended to
  be selected from a predefined set of values with specific semantic
  aspects that are assigned to the element, such as those defined in the
  ARIA ontology, XHTML Role Attribute Module, XHTML Vocabulary
  collection, and in future SVG specifications.
   — http://dev.w3.org/SVG/profiles/1.2T/publish/struct.html#RoleAttribute

It then goes on to describe a "contexthelp" role.  It looks like this is
being defined by SVG Tiny 1.2.  (I couldn’t find it in the ARIA ontology
or XHTML Vocabulary collection.)  Is this the only role SVG Tiny 1.2
defines?  Perhaps the quoted paragraph above should also mention that
the attribute is also intended to use role values defines in this

I’m not clear on why "contexthelp" is defined here rather than
recommending the use of ARIA’s "tooltip" role.  Is there a distinction
that I’m missing?

How do you associate the context help element with the element that it
is the context help for?  For example, with ARIA's "tooltip" you would
use an @aria-describedby attribute on the element that is being
described by the element with role="tooltip".  There doesn’t seem to be
an equivalent attribute for use with "contexthelp".  IIUC I think I’d
need to be able to do something like the following:

  <svg …>
    <g id='Window1' transform='…'>
      <g id='Button1' describedby='ContextHelp'>
    <g id='ContextHelp' transform='…' role='contexthelp'>
      <rect width='200' height='20' rx='5' fill='yellow'/>
      <image xlink:href='info-balloon.png'
             x='5' width='20' height='20'/>
      <text x='30' y='15' font-size='10'>
        Click this button if you rock!

I find it a little odd that the "contexthelp" role is defined here not
only to inform an AT of the association between an element and some
graphical content (or textual, if used on a descriptive element) that
forms a context help popup, but also to cause some particular visual
processing when used on descriptive elements.  Are roles not meant
solely for authors to provide hints to ATs on how (in our case)
graphical content maps to structural UI concepts, such as widgets,
tooltips and so on?  Should including a role really induce particular
behaviour in the SVG user agent too?

I admit I’m a bit of a chobo when it comes to ARIA and roles and so on,
so if I’m misunderstanding the whole thing please do set me straight.



Cameron McCormack ≝ http://mcc.id.au/
Received on Tuesday, 21 October 2008 11:39:27 UTC

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