Al Gilman, Rhys Lewis and Rotan Hanrahan
Two somewhat related issues that could be important to the Backplane have been identified by WAI and DIWG.
The first of these relates to the need for more flexible ways to link Gestures and Actions, than is available from current approaches based on the concept of fixed shortcuts (accesskey). The second relates to the need to allow users to express preferences via the delivery context [1].
For reasons of both accessibility and device independence there is a pressing need for a more flexible way to represent gestures, actions and the binding between them. In this context, gestures are operations that a user can carry out via a user interface. Examples include pressing a button, speaking a keyword and tapping with a stylus. Actions are operations supported from the current Web page. These might include traversing a specific link, submitting a form or activating a menu. Some work has already been undertaken in this area [2]. Approaches to identifying actions in specific domains has also been undertaken [3] [4] [5].
Current systems, such as the accesskey mechanism in HTML, bind a particular gesture to an action in the markup. This is sufficient when users are accessing the web via conventional personal computers or workstations. However, when users have disabilities, or where they are using non-traditional methods for web access, this mechanism is wholly inadequate. Authors cannot cater for such situations with current mechanisms, which simply assume the availability of particular input modes and device capabilities.
We'll discuss the need for more abstract representations that can support binding of gesture to action late in the overall processing of a page. Such approaches can support device independence, use of assistive technologies, and expression of user preference.
The need for users to express preferences about the way they interact with the Web becomes more pressing for users with disabilities and for users who choose to use non-traditional devices for access. The binding of gesture to action is one example of such preferences, but there are many others.
We'll discuss a number of requirements for expressing user preferences as modifications to the delivery context.
[1] The definition of delivery context in the DIWG Glossary of Terms for Device Independence R.Lewis, W3C Working Draft, 2005 (see http://www.w3.org/TR/di-gloss/)
[2] Intent Based Events S. Pemberton et al. W3C Working Draft, November 2003 (see http://www.w3.org/MarkUp/Forms/Group/Drafts/1.1/intent-based-events.html)
[3] ISO Danger and Information Signals
[4] ETSI Spoken command vocabulary for ICT devices and services
[5] EZ Access (R)