DHTML menus and accessibility

We had this discussion on the Webdesign-L mailing list on the topic 
of DHTML navigation-- those jazzy menubars that pop up outta nowhere:

>What happens if you have a DHTML navigation system that pops up or 
>drops down submenus as you drag a mouse across a menu bar? 
>Presumably the screen reader is chugging it's way through the 
>content of the page when you drop the submenu. Can the screen reader 
>even recognize that a submenu has been dropped, let alone read it?

And I wrote back that there were two obvious possibilities

>In your DHTML drop-down menu, you've set things up as a collection 
>of individual graphics, each with an ALT and TITLE.
>
>Or:
>
>You have set up clickable hotspots in your single graphic image, 
>each of which has an ALT and TITLE. (This doesn't quite take care of 
>the other instructions you may have embedded as bitmapped type 
>inside the graphic.)
>
>If either of these is possible, theoretically a screen reader could 
>read the ALT or TITLE and let the user know it's actually there.
>
>Now, as to the issue of even recognizing that something has happened 
>at the DHTML level, I wish I knew.

So here are a few questions for WAI-IG:

* Do current screen readers even recognize when a DHTML menu drops down?

* If it contains ALTs and TITLEs, can the screen reader navigate it? 
What about the fake close boxes used in some such menus? Will the 
screen reader even recognize the existence of that close box, given 
that there is no standardized data format to mark up a close box as 
such?

If you're interested in looking at a few examples of DHTML 
navigation, I've covered the topic extensively on the NUblog Weblog 
on online content:

<http://www.contenu.nu/200004.html#ettusais>
<http://www.contenu.nu/200006.html#jumpout>
<http://www.contenu.nu/200007.html#interfacetrickery>
<http://www.contenu.nu/nublog.html#moreinterface>

(Those discussions are fully accessible, with ALTs, TITLEs, and-- 
wait for it!-- LONGDESCs on any graphical elements.)

Any wisdom to share on how screen readers handle DHTML navigation?

Please reply direct, and Cc: to the list.
-- 

    Joe Clark | joeclark@contenu.nu
    Taste | Acumen | Content -- <http://www.contenu.nu>
    (Weblog on online content: <http://www.contenu.nu/nublog.html>)
    www.fawny.org | www.joeclark.org | www.electricseed.com/joeclark

Received on Tuesday, 15 August 2000 12:28:05 UTC