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Re: alert issue

for

From: glen walker
Date: Jul 2, 2018 12:18PM

Hi Carmen,

One clarification on what your developer said. They said they tried
aria-live of polite and assertive and then "replaced the aria-live method
with a role of alert, and this caused the change to be announced
immediately".

A role="alert" gives you an implicit setting of aria-live="assertive", so
your developer hasn't really replaced aria-live. They still have aria-live
but it's implied in the role="alert".

They should have heard the changes announced immediately by simply using
aria-live="assertive", however, that might not be the proper setting in
your case.

Using aria-live="assertive", or more extreme, using role="alert", should be
reserved for truly time-sensitive alerts that might cause problems if the
user were not notified immediately. When calculating college costs by
selecting various options (such as in-state or out-of-state), to me, that
doesn't seem like an urgent message and aria-live="polite" should suffice.
Suppose a screen reader user has visited that page several times because
they're trying various options over the span of several days. They will be
used to the layout of the page by then and could quickly navigate to
several options and select them. After each option is (quickly) set,
having the total amount updated every time after an option changed by using
role="alert" would be audible noise. They'd want to hear the changes after
they selected all the options, which is what should happen with
aria-live="polite". If options were changed slowly, then you'd still hear
each aria-live update individually, but if you change options quickly,
hopefully the screen reading software queues all the changes and coalesces
them into one announcement.

You start getting into dangerous waters if a non-screen reader user
attempts to guess at what a regular screen reader user might want.

Now, all this is sort of beside the point of your original question, that
radio buttons and aria-live changes seem to be lost. I do know that with
aria-live="assertive" (whether that's set directly or implicitly by using
role="alert"), that screen reading software has the option to clear all
other pending live announcements. "User agents or assistive technologies
MAY choose to clear queued changes when an assertive change occurs". See
https://www.w3.org/TR/wai-aria-1.1/#aria-live. So that *might* be causing
the behavior you're seeing.

If you had test versions of the various aria-live options, that would help
us figure out the problem.

Glen