- From: Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>
- Date: Sat, 1 Feb 2014 22:10:35 +0100
- To: James Craig <jcraig@apple.com>
- Cc: Joanmarie Diggs <jdiggs@igalia.com>, Cynthia Shelly <cyns@microsoft.com>, Bryan Garaventa <bryan.garaventa@whatsock.com>, "T.V Raman" <raman@google.com>, "jongund@illinois.edu" <jongund@illinois.edu>, "jason@jasonjgw.net" <jason@jasonjgw.net>, "wai-xtech@w3.org" <wai-xtech@w3.org>, "w3c-wai-pf@w3.org WAI-PFWG" <w3c-wai-pf@w3.org>
Leif Halvard Silli, Sat, 1 Feb 2014 21:54:48 +0100:
>>>
>>> I think role="flat", role="flattened" or role="flatten" are better.
>>> Because, what presentation role does is that it flattens the signals
>>> from many to just one. E.g. for <img>, it flattens the two layers -
>>> alternative text and picture - into just one thing - picture.
>>
>> I think you’re misunderstanding how this works on images.
>
> Why do you think so?
>
>> In all
>> cases, the presentation role removes any implicit role mapping (e.g.
>> <h2> no longer maps to “heading”) and therefore any attributes
>> associated with that role (e.g. @alt on img) are also deemed
>> irrelevant.
>
> Here you say that it as expected that presentation role silences @alt,
> whereas below ...
>
>> The fact that it works this way on HTML images is just an
>> artifact of the host language that puts the alternative text in an
>> attribute instead of the child contents.
>
> … here you say that is an artifact. I don’t think it is an artifact
> since, if you removed @alt and added @aria-label, then the @aria-label
> would be silenced by the role="presentation".
Regarding this claim about misunderstanding … ;-) My thinking is based
on something from the accessible name calculation.[1] Namely the
separation between “author” content and ”content” content. So my basic
thinking is that role="presentation", for the element to which it is
applied (and the elements that it “governs”) causes AT to ignore, quote:
“values provided by the author in explicit markup features such
as the aria-label attribute, aria-labelledby attribute, or the
host language labeling mechanism, such as the alt or title
attributes in HTML, with HTML title attribute having the lowest
precedence for specifying a text alternative”
However, “the text value of the element node“ is not ignored.
[1] http://www.w3.org/TR/wai-aria/roles#namecalculation
--
leif halvard silli
Received on Saturday, 1 February 2014 21:11:36 UTC