DHTML - thoughts and concerns

Dynamic HTML - the use of active components to provide special features
within a web page, is accomplished in a number of ways.

Some of these, such as the use of applets or scripts, rely on technologies
which may not be widely implemented in an accessible fashion. There are
guidelines which address this problem already - in particular, provide
alternative content, and ensure that user interface components are made in
an accessible manner.

Others rely on device-dependent approaches. The most common of these is
the use of mouse-generated events. There are very few ways, currently, to
make these accessible. Therefore, their use should be restricted to events
which make no substantive changes, or the events should also be
triggerable by accessible means, such as the conventional activation of
links or buttons. It is important to ensure that the user knows what a
trigger will do. At the moment, the only way to provide this information
is by adding it to the page content. Again these are addressed within the
current guidelines, particularly a9, a11, a12 and a13, although they are
also covered to some extent by guidelines b1 and b2.

Further development of these technologies will include further development
of strategies to render them accessible. In some cases, this will require
changes to existing documents, although it is to be hoped that this will
be rare. Careful consideration of the implications of accessibility
requirements, and attention to new developments, should enable authors to
avoid such situations.

CMN: I feel like this is still a bit heavy going. Do people on the list
get it? (If you guys don't then it needs really serious work. If you do,
then it needs some fairly serious work. It is also kind of vague. It would
be nice to say 'look for WCGL 2' or something. Sigh.

Some of this relates to some work that is being done or considered by PF,
but since that group is member-confidential it is a bit difficult to just
incorporate it into the guidelines...

Charles

--Charles McCathieNevile            mailto:charles@w3.org
phone: +1 617 258 0992   http://purl.oclc.org/net/charles
W3C Web Accessibility Initiative    http://www.w3.org/WAI
MIT/LCS  -  545 Technology sq., Cambridge MA, 02139,  USA

Received on Monday, 22 February 1999 17:53:26 UTC