RE: Discussion of DOM with Glen Gordon of Henter-Joyce

Hi:

Since my name seems to have become somewhat famous as the subject of
so many messages  in the past few days, I decided I should probably
clarify my original answers to John and prove that I can communicate
in slightly more than monosyllabic words.

The preference I express for using a DOM rather than a more generic
approach like MSAA  stems entirely from the fact that a DOM inherently
offers a richer array of information.  This clearly is a double-edged
sword since using a DOM requires additional coding to get at this
richer information set.  However, if the assistive technology tool has
a scripting language which allows for accessing this information, then
the efforts involved to incorporate it is greatly reduced and can
often be done by members of the user community who embrace that tool.
I am not advocating that MSAA and similar approaches be abandoned.
Rather, I am saying that approaches to presenting information in
uniform manner be based on DOMs.  (This, as I understand it, is
largely the approach MSAA has taken in supporting IE4.)  If the
accessibility aid wishes to go the extra mile and take advantage of
the richer information set provided by a DOM, it should be encouraged
to do so.  In the case of JFW, we have chosen to use the IE4 DOM in an
effort to more accurately predict the prompts which are
associated with input fields on a form.  Without access to the
the underlying HTML tags, doing this is much more difficult and much
more error prone.  Even if MSAA were to engage in prediction of field
prompts on HTML forms, who is to say  that all accessibility aids will
be happy with the approach that MSAA used.  By making DOM information
available, there exists the chance that some ISVs will go the extra
mile and provide a more robust interface than that which is possible
using something like MSAA which can probably never be all things to
all applications.


--Glen

Received on Tuesday, 9 February 1999 09:52:45 UTC