Re: [NVDA] #2390: NVDA doesn't handle role=dialog with supporting ARIA attributes according to spec

James,

The presentation role actually had two purposes.  One is to suppress the
native role of an element and required descendants (but not text nodes).
 The other is to influence the naming of controls



Regarding naming widgets - ARIA have a document titled "ARIA User Agent
Implementation Guide".  This guide has a section titled "Name and
Description".  In this section are specific instructions that assistive
technologies (user agents) are supposed to use to determine the name for a
widget.



My reading of rule 2A indicates that role of presentation should affect
whether the item is used for naming.



If aria-labelledby and aria-label are both empty or undefined, and if the
element is not marked as presentational
(role="presentation<http://www.w3.org/TR/2011/CR-wai-aria-20110118/roles#presentation>
", check for the presence of an equivalent host language attribute or
element for associating a label, and use those mechanisms to determine a
text alternative. For example, in HTML, the img element's alt attribute
defines a label string and the label element references the form element it
labels. See How to Specify Alternate
Text<http://www.w3.org/TR/REC-html40/struct/objects.html#h-13.8>
 ([HTML <http://www.w3.org/TR/wai-aria-implementation/#ref_HTML>], section
13.8) and HTML5 Requirements for providing text to act as an alternative
for images<http://www.w3.org/TR/2010/WD-html5-20100624/embedded-content-1.html#alt>
([HTML5 <http://www.w3.org/TR/wai-aria-implementation/#ref_HTML5>], section
4.8.1.1). In the case of HTML frame and iframe elements, the title element
in the head element of the document inside a frame or iframe is used in
this step of the calculation of the name of the frame or iframe.



Hence, AT should be using the label for the label and then ignoring items
in the presentation for labels and descriptions.  For situations where
there is no label and only content within the dialog that has a role of
presentation then my assumption is that no label would be announced.



Jonathan

Received on Wednesday, 30 May 2012 22:22:55 UTC