RE: DHTML, Front Page Transitions - Accessible Standards
by "John Foliot - Another 4:00 AM Web Thing" <foliot(at)fouram.com>
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Date: |
Mon, 18 Feb 2002 15:31:00 -0500 |
To: |
"John Brandt" <jbrandt04330(at)earthlink.net> |
Cc: |
"Aware-Techniques" <aware-techniques(at)hwg.org> |
In-Reply-To: |
earthlink |
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todo: View
Thread,
Original
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John,
Never one for FrontPage anything, I suspect what you are talking about is
the "funky" page transitions I've seen from time to time on the web. An
actual example URL would have been nice.
However, I might point out the following:
WAI Priority 1:
6.3 Ensure that pages are usable when scripts, applets, or other
programmatic objects are turned off or not supported. If this is not
possible, provide equivalent information on an alternative accessible page.
(Do the transitions impede the delivery in, say, Lynx?)
7.1 Until user agents allow users to control flickering, avoid causing the
screen to flicker.
WAI Priority 2:
7.2 Until user agents allow users to control blinking, avoid causing
content to blink.
7.4 Until user agents provide the ability to stop the refresh, do not
create periodically auto-refreshing pages.
7.5 Until user agents provide the ability to stop auto-redirect, do not use
markup to redirect pages automatically.
If your FP transitions do any of the above, they are not WAI compliant (if
it's the 6.3 or 7.1 it's non 508 compliant...). I have read the W3C's
definitions about "7.1" many times; they are frustratingly vague on the
definition of "flicker", although they do state:
"Note. People with photosensitive epilepsy can have seizures triggered by
flickering or flashing in the 4 to 59 flashes per second (Hertz) range with
a peak sensitivity at 20 flashes per second as well as quick changes from
dark to light (like strobe lights)."
My interpretation is a little broader... flickering is random flashes of any
type at any speed, which _may_ include your transitions. However, this
appears to be one of those "judgemental" standards (similar to "When is it
appropriate to use the LONGDESC attribute?")
As far as your JavaScript is concerned:
1) the <Script> tags should contain both the language and the type like so:
<script language="JavaScript1.2" type="text/javascript">
</script>
2) you mentioned that the HTML validator did not like the "fptype"
attribute. Which DTD did you use? Which validator? If it was the W3C Public
HTML4.01 Transitional, then no, it won't validate. However, if it's
*Really* important, you can always create your own DTD
(http://www.htmlhelp.com/tools/validator/customdtd.html) and still be
compliant (Priority 2: 3.2 Create documents that validate to published
formal grammars.) Although not hard to do, creating your own DTD is not
trivial... You might search Microsoft's site to see if they still have
their own DTD (they used to have one for Internet Explorer but I'm not sure
if they still support and publish their own any more) If they do, it *might*
accept that attribute (you would presume...)
Hope this helps.
JF
> -----Original Message-----
> From: owner-aware-techniques(at)hwg.org
> [mailto:owner-aware-techniques(at)hwg.org]On Behalf Of John Brandt
> Sent: February 18, 2002 2:30 PM
> To: aware-techniques(at)hwg.org
> Subject: DHTML, Front Page Transitions - Accessible Standards
>
>
> I am wondering if the features built into Microsoft's Front Page called
> "Page Transitions" meet the accessibility standards. For those of you
> unfamiliar with Front Page (FP), these are meta tag codes that insert the
> following information:
>
> <meta http-equiv="Page-Enter"
> content="revealTrans(Duration=1.0,Transition=0)">
> <meta http-equiv="Page-Exit"
> content="revealTrans(Duration=1.0,Transition=8)">
>
> The cause a special effect when the web page loads and when one
> moves on to
> another page. There are a variety of these that can be programmed
> into a FP
> web page, however my understanding is that they can only be
> viewed with the
> Internet Explorer browser.
>
> I tested a page using these with Bobby and the W3C Validators and both
> passed the page. I also included some DHTML code (see below) and
> they still
> passed.
>
> However, the DHTML code failed in the HTML 4.0 validator since it
> used some
> funky code that is not valid:
>
> <script language="JavaScript" fptype="dynamicanimation">
>
> and...
>
> <script language="JavaScript1.2" fptype="dynamicanimation"
> src="../animate.js">
> </script>
>
> CSE HTML Validator did not like the "fptype" code and did not recognize
> "JavaScript1.2" as a valid language.
>
> So the question is...if these types of FP features are used will
> it make the
> page inaccessible to AT devices?
>
> Thanks for any comments
>
> John E. Brandt
> Augusta, ME 04330
>
> jbrandt04330(at)earthlink.net
> home.earthlink.net/~jbrandt04330
>
>
>
>
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