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Re: javascript

for

From: Carol Foster
Date: Sep 6, 2001 7:45PM

Hello,
I find the approach of assuming JavaScript is turned on and is accessible of
concern both for accessibility and for security. People can turn off
JavaScript, and some people do so, sometimes because they are concerned about
their own privacy. Developers should not count on JavaScript for any kind of
security check, such as passwords, or any kind of message that they want to be
sure the user can access. The best approach seems to me to be to put any checks
on data entry, or messages to the user, in BOTH JavaScript and on the server
side. Even if the latest version of JAWS supports JavaScript, earlier versions
do not. Nor may other browsers or user agents, such as lynx (the version I test
with does not support JavaScript).
As I understand it, Section 508 covers new procurement for the Federal
government, so maybe it makes sense for them to expect that new purchases would
be top of the line, like JAWS 3.7. To be accessible to the widest possible
audience, however, that is a lot to ask. Maybe that accounts for apparent
differences in the Section 508 and WAI philosophies?
Web applications like online shopping and distance learning can be of great
service to many people, including some that don't have a lot of choice in their
user agents, e.g. because they use computers in libraries. Especially for these
types of applications, but probably for everything, I would go along with the
WAI and recommend that these sites work with or without JavaScript, if it were
up to me! From my understanding of the technology, this does not seem to be one
of the hard ones, though it does take a some extra time and effort.
Best wishes,
Carol
Reidy Brown wrote:
> Lisa,
>
> Clarification: The whole Javascript explanation is mine (one I wrote to the
> WAI-IG list several months ago). I wanted to make sure I had it right, so I
> sent it to Doug, and he ok'd it, and sent me this additional info:
>
> [Doug]
> What problems do screen readers confront with scripting languages?
>
> This standard requires web page authors to ensure that all the information
> placed on a screen by a script shall be available in a text form to
> assistive technology. Standards for scripts (l) and applets and plug-ins (m)
> have similar purposes. Web page authors have a responsibility to provide
> script information in a fashion that can be read by assistive technology.
> When authors do not put functional text with a script, a screen reader will
> often read the content of the script itself in a meaningless jumble of
> numbers and letters. Although this jumble is text, it cannot be interpreted
> or used.
>
> How can web developers comply with this standard?
>
> Because of the problems described above, the standard requires that
> functional text be provided, that is, text that, when read, conveys an
> accurate message as to what is being displayed by the script. For instance,
> if a web page uses a script only to fill the contents of an HTML form with
> basic default values, the web page will likely comply with this requirement,
> as the text inserted into the form by the script may be readable by a screen
> reader. By contrast, if a web page uses a script to create a graphic map of
> menu choices when the user moves the pointer over an icon, the web site
> designer may be required to incorporate "redundant text links" matching the
> menu choices because functional text for each menu choice cannot be rendered
> to the assistive technology. Determining whether a web page meets this
> requirement may require careful testing by web site designers, particularly
> as both assistive technology and the JavaScript standard continue to evolve.
> [End Doug's explanation]
>
> Reidy
>
> -------------------------------------------
> Reidy Brown
> Accessibility Coordinator/Sr. Software Engineer
> Blackboard, Inc.
> (202) 463-4860 x236
> -------------------------------------------
> Blackboard 5.5 Fully Implements Section 508 Accessibility Standards!
> Learn more:
> http://products.blackboard.com/cp/bb5/access/index.cgi
> -------------------------------------------
>