[techs] Auto submit combo boxes - Bugzilla 272

In the current draft of the HTML techniques [1], the last technique is a
place holder for "auto-submit" combo boxes. It refers to Bugzilla issue 251
[2]; it should refer to 272 [3].


I think auto-submit combo boxes, i.e., select menus with an onChange event
handler, which open a new page should be discouraged because of the likely
pitfall for keyboard users of hitting up and down arrow when arriving at the
control and triggering on the first movement. Particularly, JAWS actually
says "use up and down arrow to select" (or something like that). But as we
all know, alt-down-arrow should be used first to open the list and then the
arrows can be used with enter to activate. 


There is such a select menu (for language selection) on http://cnn.com
<http://cnn.com/>  at the bottom of the page. I checked the alt+down-arrow
behavior on IE6, Netscape 7, Mozilla 1.7 and Opera 7.5. 


However if the size of the select menu is greater than 1, e.g. size="2",
keyboard navigation is broken in all the browsers. With size greater than 1,
the browsers consider the list to be open; alt+down-arrow does nothing, and
moving with the arrow keys fires the on-change event. (You can try this by
looking up "blind" in the on-line dictionary at http://m-w.com
<http://m-w.com/> .) 




I think this technique should recommend not using on-change event handlers
for select menus (which cause a page to open) and using a submit button
instead. If some design principle demands the use of onChange, a title
attribute can clarify the issue, like this: title="Use alt down arrow to
open a list of languages."


Select menus with size>1 (that open a new page) must use the submit button
instead of triggering with the onChange event because they cannot be used
with the keyboard.




I added "which cause a page to open" to the statements above. Really the
worrisome situation, is "cause the input focus to change" because if the
input focus does not change the keyboard user can continue down the list
even though things may be happening (like repopulation of select menus)
because the onChange event is triggering on each item in the list.


[1] http://www.w3.org/WAI/GL/WCAG20/WD-WCAG20-HTML-TECHS-20040726.html 

[2] http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=251 

[3] http://trace.wisc.edu/bugzilla_wcag/show_bug.cgi?id=272 



Accessibility, What Not to do: http://jimthatcher.com/whatnot.htm.

Web Accessibility Tutorial: http://jimthatcher.com/webcourse1.htm.


Received on Wednesday, 28 July 2004 12:26:41 UTC