Accessibility Notes: 2nd August 2011

Bits & Bobs about web accessibility.

HTML5 details and summary elements

Have been looking into the chrome (13.0.782.107 beta-m) implementation of HTML5 details and summary elements. Bottom line is, currently no keyboard support and no usable information exposed to assistive technology.

ARIA Landmark support in VoiceOver on Mac OS X 10.7 Lion

Roger Johansson reports on Accessibility in Mac OS X 10.7 Lion. Including details about VoiceOver on OSX 10.7 Lion now supporting ARIA landmarks:

VoiceOver now lets you use ARIA landmarks, if they are present, to navigate web pages. If Quick Nav is active you can use the w and W keys to navigate to the next or previous landmark. When you use the arrow keys to navigate around a page, VoiceOver announces when you enter and leave landmarks, including the type of landmark (for example “Leaving main landmark, entering complementary landmark”).

vision australia versions of the Web Accessibility Toolbar and Color Contrast Analyser

Worked with my old employers vision australia to make updated versions of the Web Accessibility Toolbar and Color Contrast Analyser available for download on their site.

Funky aria-describedby and aria-labelledby support in IE9

• Looked into the aria-describedby and aria-labelledbytest cases provided by Todd Kloots, generated some further test cases from his, and found that:
  • latest versions of NVDA and JAWS used with  IE 9 will not announce descriptions unless tabindex=-1 is added to  elements such as p, div and span when referenced from aria-describedby or aria-labelledby that reference multiple elements:
    • <input type="text" aria-labelledby="label1 label2">
    • <input type="text" aria-describedby="desc1 desc2">
  • As I found previously, aria-describedby with a single reference:
<input type="text" aria-describedby="desc1">
    does not result in the MSAA acc-description property being populated with the text content of the referenced element, but in testing it with NVDA and JAWS found it still worked.  (i.e the description was announced when the control recieved focus.)
  • asked@jcsteh how NVDA accesses the aria-describedby text in IE when it is not provided via the MSAA accessible description property Jamie responded: “We pull it from the DOM… which we have to do for a lot of stuff in IE. :(“

HTML5 and ARIA Boolean attributes

• Clarified with @stommepoes that ARIA boolean attributes do not work the same as HTML5 boolean attributes, for example:
  • In HTML5 native boolean attributes <input type=text required> the presence of the attribute indicates the true state while the abscence indicates the false state: <input type=text>
  • But even when used in HTML5 <input type=text aria-required> the presence of the aria-required attribute does not indicate the true state. The value needs to be expliclty declared: <input type=text aria-required="true">

HTML5 accessibility change proposal

Completed a change proposal to overturn the W3C HTML working group decision that the presence of <meta name=generator> in a HTML document results in conformance checkers such as the W3C validator hiding alt errors.