Re: ARIA: Why is role="marquee" necessary? We already have role="log"

role="marquee" is not like log, because in a marquee changes tend to be 
fast and constant. Typically you don't want to hear all the items as they 
scroll by in a marquee, because of the constant chatter that would entail. 
Therefore the default aria-live value for marquee is "off". Similar for 
role="timer" -- that's off by default as well.

The concept is that where we can think of a very typical live region use 
case, ARIA provides a role. This is a higher level semantic and is easier 
for authors to know they're doing the right thing. They might not be sure 
whether a marquee/timer/log/status should be polite or off, but they can 
probably figure out that something is one of those objects.

- Aaron



From:
James Craig <jcraig@apple.com>
To:
WAI XTech <wai-xtech@w3.org>
Date:
12/08/2008 03:07 AM
Subject:
ARIA: Why is role="marquee" necessary? We already have role="log"




Why is role="marquee" necessary? We already have role="log" in the 
spec. Currently, the draft vaguely mentions, "A major difference 
between a marquee and a log is how fast it gets updates from timed or 
real world events."

Unless someone has a good reason to keep it, I propose we ditch 
"marquee" and just use "log" for all instances.