Re: [Bug 12587] AT shouldn't see img@alt="" and img@role=presentation as 100% synonyms

Richard Schwerdtfeger, Tue, 3 May 2011 09:53:49 -0500:
> Leif:
>> Steve Faulkner, Tue, 3 May 2011 14:33:58 +0100:

>> >>However, as sole content inside a link, it should probably be invalid
>> > to use role=presentation.
>> > 
>> > my understanding is that it is invalid in HTML5 
>> > 
>> http://dev.w3.org/html5/spec/embedded-content-1.html#a-link-or-

>> button-containing-nothing-but-the-image
>> 
>> That text doesn't speak about @role=presentation. It only speaks about 
>> @alt. Thus, per HTML5, this could be valid:
>> 
>> <a href="green.html"><img role=presentation src="green.jpeg" 
>> alt="Green"></a>
>> 
> In this case it should be invalid to have role="presentation" on an 
> element that has alt text that is not empty. Here the image is not 
> presentational. Also, any image with a title attribute should not 
> have role="presentation" either. 
> 
> The only time role="presentation should be allowed on an image is 
> when it does not have an form of alternative text such as:
> 
> - alt=""
> - title=""
> either alt or title are absent as properties

What if @aria-labelledby=IDREF is present?

> WCAG should require (probably does) that an image used to represent 
> the link must have alternative text. 

Today, if an image contains decorations, such a characters of a 
decorative font [1], many of us would probably consider it as a 
decorative image. And an author could for instance place those 
decorative characters inside the @alt, for fallback to text browsers. 
But perhaps it is more correct to identify such an IMG as having 
role=separator? [2] Always?

Note, anyway, that nothing in HTML5 currently says that 
role=presentatation is illegal on an image with @title.

[1] http://www.linotype.com/57368/linotypedecorationpi1-font.html

[2] http://www.w3.org/TR/wai-aria/complete#separator

-- 
leif halvard silli

Received on Tuesday, 3 May 2011 16:13:26 UTC