Accessibility Considerations for Design Patterns

[Anastasia Cheetham]

Mike, this looks really good.

In the Design Pattern Accessibility page, you may wish to add  
information about the work that WAI is doing as part of their  
Accessible Rich Internet Applications (ARIA) suite of specifications.  
Their roadmap document
     http://www.w3.org/TR/aria-roadmap/
provides an overview of the specifications.

Currently, HTML only allows script authors to place focus on form and  
anchor elements. Much of today's markup is structured such that  
effective navigation requires focus on other types of elements, such  
as div elements.

The WAI ARIA work is incorporating a feature into Firefox and IE to  
support a tabindex value of -1, to allow scripts to set focus on  
elements that are not within the regular tab order. This is described  
in more detail in section 5.1.3 of the document:
   http://www.w3.org/TR/aria-roadmap/#focus

There is also an 'activedescendent' attribute which indicates which  
child element of a currently focussed element is active. The Fluid  
Lightbox component uses this attribute to indicate which thumbnail in  
the Gallery collection is currently active when the Lightbox itself  
has focus.


This information is specified in detail in the States and Properties  
specification:
     http://www.w3.org/TR/aria-state/
in particular:
     http://www.w3.org/TR/aria-state/#focus


-- 
Anastasia Cheetham                   a.cheetham at utoronto.ca
Software Designer, Fluid Project
Adaptive Technology Resource Centre / University of Toronto

               ygUDuh

                   ydoan
                   yunnuhstan
                         -- E.E. Cummings