Overview
The PFWG generally looks at formal specifications being developed in other W3C non-WAI groups and provides feedback on enhancements to the specifications that support accessibility. The group does not usually produce W3C specifications.
Recent work, however, is focused on dynamic Web content and rich Internet applications that are developed with AJAX, DHTML, and other Web technologies. The PFWG defines how to make more advanced features of dynamic content and rich Internet applications accessible to people with disabilities. A primary focus is providing information about user interface controls-such as expanding navigation bars-to assistive technology.
The working group has another focus: fixing the accessibility of Rich Internet Applications. The inaccessibility of these applications has often been categorized as the "JavaScript Accessibility Problem." These applications make use of script to re-purpose existing markup to create new application widgets not defined by the format. The accessibility of markup languages, such as XHTML and HTML, depends on the coordination of content and presentation. There is an accessibility problem when rich interaction semantics are added outside the markup. When this happens, the markup no longer expresses the information needed to populate accessibility metadata mapped by the browser to platform accessibility APIs. These accessibility APIs inform assistive technologies of essential knowledge about the interactive objects, and allow the assistive technologies to adapt the presentation of information and the acceptance of user input in a way suitable for the individual user.
PFWG work has been divided into three documents. The current working drafts of these are:
- Roadmap for Accessible Rich Internet Applications (ARIA): The ARIA roadmap is a specification that describes techniques for the creation of fully accessible user interface components (a.k.a. widgets) that mimic the behavior of desktop components. These techniques are based on AJAX, DHTML, and other Web 2.0 emerging technologies. It outlines the technologies to map controls, AJAX live regions, and events to accessibility APIs, including custom controls used for Rich Internet Applications. The roadmap also outlines new navigation techniques to mark common Web structures as menus, primary content, secondary content, banner information and other types of Web structures. IBM is the primary author of this document.
- Roles for Accessible Rich Internet Applications (ARIA): This specification defines the RDF taxonomy of roles to describe custom GUI widgets and document structure which may be used to support platform accessibility APIs. Roles encapsulate semantic information which may be used to help user agents support assistive technologies, authoring tools enforce accessibility, and assistive technologies recognize new custom objects and determine how to interoperate with them. IBM is one of the principal authors of this document.
- States and Properties Module for Accessible Rich Internet Applications (ARIA): This specification defines attributes that provide XML languages with the ability to add extra information about the behavior of an element. States and adaptable properties are mapped to accessibility frameworks (such as a screen reader) that use this information to provide alternative access solutions. Similarly, state and author properties can be used to dynamically change the rendering of content using different style sheet properties. The result is to provide an interoperable way for associating behaviors with document-level markup. Additionally, this specification includes markup to fix keyboard focus problems with today's XHTML 1.X markup. Two members of the IBM SWG Emerging Internet Technology team are principal authors of this document.
The IBM SWG Emerging Internet Technology team has written an additional suggestion document for the W3C: Embedding Accessibility Role and State Metadata in HTML Documents. Because the ARIA methods using XHTML markup defined in the above documents cannot be used directly in HTML documents, this document defines how to declare accessibility semantic information within an HTML document and how to use a script library to retrieve that information for a user agent to pass on to an assistive technology.
Last updated, July 27, 2007