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Thread: Technical explanation on how Flash interupts screen readers

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From: Birkir RĂșnar Gunnarsson
Date: Sun, Nov 14 2010 8:09AM
Subject: Technical explanation on how Flash interupts screen readers
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Hello everyone

I need to convince a public media web site in my native country to
stop, or reduce, their usage of Flash, since the Flash movies on their
web site make it nearly impossible for me to read it by now, the Jaws
scursor jumps all over the page and I cannot click on the links I plan
to click on.
To clarify, the web site is www.mbl.is (it is all in Icelandic).
Is there a good explanation somehwere on what type of Flash interups
screen reading and how that happens?
I believe the Flash objects send out events that the screen reader
interpetes as page refreshes and the cursor tries to jump to that
area, but I may not be understanding this process correctly.
If anyone can point me to a resource on this that would be very helpful.
Thank you
-Birkir

From: Andrew Kirkpatrick
Date: Mon, Nov 15 2010 6:57AM
Subject: Re: Technical explanation on how Flash interupts screen readers
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Birkir,
I believe that the issue with that site is how the Flash content is created, not necessarily that it is in Flash. The authors could easily hide the motion from JAWS and other screen readers, but haven't. I'm not sure why JAWS is jumping all over the page for you though. You mention the JAWS Cursor - do you mean the JAWS cursor or the Virtual PC Cursor?

Thanks,
AWK

Andrew Kirkpatrick
Group Product Manager, Accessibility
Adobe Systems

= EMAIL ADDRESS REMOVED =
http://twitter.com/awkawk
http://blogs.adobe.com/accessibility


From: Birkir RĂșnar Gunnarsson
Date: Mon, Nov 15 2010 7:12AM
Subject: Re: Technical explanation on how Flash interupts screen readers
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I do mean the virtual PC cursor, sorry for that confusion.
If you have technical resources for me on how authors can hide the
motion from a screen reader user, that would be ever so helpful.
I know that Flash, by itself, does not necessarily constitute
accessibility issues.
However I need to get down to a somewhat more technical level of when
it does so and how that can be corrected, ideally without affecting
the intended visual appearance.
I realize I may have to get quite technical to get there, but any
pointers would be helpful.
Thanks
-Birkir


On 11/15/10, Andrew Kirkpatrick < = EMAIL ADDRESS REMOVED = > wrote:
> Birkir,
> I believe that the issue with that site is how the Flash content is created,
> not necessarily that it is in Flash. The authors could easily hide the
> motion from JAWS and other screen readers, but haven't. I'm not sure why
> JAWS is jumping all over the page for you though. You mention the JAWS
> Cursor - do you mean the JAWS cursor or the Virtual PC Cursor?
>
> Thanks,
> AWK
>
> Andrew Kirkpatrick
> Group Product Manager, Accessibility
> Adobe Systems
>
> = EMAIL ADDRESS REMOVED =
> http://twitter.com/awkawk
> http://blogs.adobe.com/accessibility
>
>
>

From: Andrew Kirkpatrick
Date: Mon, Nov 15 2010 7:42AM
Subject: Re: Technical explanation on how Flash interupts screen readers
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Birkir,

There are a few options, but for the banner ads the mbl.is site should tell the ad-providers to take a couple of steps to make the ads accessible. Since the banner ads that I see on the site are often just a link to the advertisement site, the structure of the Flash ad could be simplified to be an invisible button that covers the entire Flash content area, and that button has a name which is descriptive of the advertisement (e.g. "Advertisement: Bank of Iceland offers 4% 30-year mortgages with no points. Click to view details"). Then, the dynamic content that is seen (and that is likely to cause any issues you are experiencing due to refreshing content) can be hidden from assistive technologies by setting the AccessibilityProperties.silent property to true for a movie clip that contains all of the other content in the ad.

The RNIB used to have guidelines for accessible banner ads but I don't see it on their site now. I'll made up a quick example...

Thanks,
AWK

Andrew Kirkpatrick
Group Product Manager, Accessibility
Adobe Systems

= EMAIL ADDRESS REMOVED =
http://twitter.com/awkawk
http://blogs.adobe.com/accessibility


From: deborah.kaplan
Date: Mon, Nov 15 2010 8:03AM
Subject: Re: Technical explanation on how Flash interupts screen readers
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Birkir wrote:

> I know that Flash, by itself, does not necessarily constitute
> accessibility issues.

Sure it does. The most accessible Flash in the world is still
something keyboard users can't escape without using the mouse.
The only way to avoid this is by hiding the Flash from the user
and replacing the controls with javascript/HTML, as Terrill
Thompson did with
<http://terrillthompson.com/tests/flash-yahoo3.html>;.

Until this is fixed, there is no such thing as truly accessible
Flash embedded in a web page.

-Deborah

From: Andrew Kirkpatrick
Date: Mon, Nov 15 2010 8:15AM
Subject: Re: Technical explanation on how Flash interupts screen readers
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Deborah,
That is a overgeneralization that is simply not accurate. The experience for keyboard only users is not even across all user agent, that is accurate to say, but to state that keyboard users can't escape Flash content without any type of clarifying information is just wrong.

Thanks,
AWK

Andrew Kirkpatrick
Group Product Manager, Accessibility
Adobe Systems

= EMAIL ADDRESS REMOVED =
http://twitter.com/awkawk
http://blogs.adobe.com/accessibility


From: Terrill Bennett
Date: Mon, Nov 15 2010 9:15AM
Subject: Re: Technical explanation on how Flash interupts screen readers
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I have no problems using JAWS or NVDA and:

Either the newest or prior version of the JW Player:
http://www.longtailvideo.com/players/jw-flv-player/

The "accessibility is one of our primary goals" player from theWorkshop:
http://www.theworkshop.co.uk/video-player

Or the ccPlayer from the National Center for Accessible Media:
http://ncam.wgbh.org/

It's a matter of who wrote the player or other Flash object that
counts. Hope this helps.

-- terrill --

At 10:00 AM 11/15/2010, you wrote:
>Birkir wrote:
>
> > I know that Flash, by itself, does not necessarily constitute
> > accessibility issues.
>
>Sure it does. The most accessible Flash in the world is still
>something keyboard users can't escape without using the mouse.
>The only way to avoid this is by hiding the Flash from the user
>and replacing the controls with javascript/HTML, as Terrill
>Thompson did with
><http://terrillthompson.com/tests/flash-yahoo3.html>;.
>
>Until this is fixed, there is no such thing as truly accessible
>Flash embedded in a web page.
>
>-Deborah
>

From: deborah.kaplan
Date: Mon, Nov 15 2010 9:51AM
Subject: Re: Technical explanation on how Flash interupts screen readers
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Terrill Bennett wrote:

> I have no problems using JAWS or NVDA and:

Keyboard control for Flash is different from screenreader
compatibility, though.

The page about Flash on the webaim site states that only Internet
Explorer/Flash on Windows allows keyboard escape. Terrill, based
on the links you sent, it looks like this information is no
longer accurate.

> http://www.longtailvideo.com/players/jw-flv-player/

This one doesn't allow pure keyboard escape in Firefox + Windows,
but it does allow access to the mouseless browsing add-on. (I
couldn't get it to recognize any other keystroke commands that
would escape from the Flash object, but in conjunction with MLB
that means you can use keyboard or voice to escape from the
object.) You can't enter the object without MLB (WCAG 2.1.1),
though. And it still keyboard traps in Opera. I can't test on
Safari or chrome.

> http://www.theworkshop.co.uk/video-player

This one doesn't seem to recognize any keystroke commands that
will escape from the Flash object, MLB or otherwise, but it DOES
allow tabbing out of the Flash object. Only player I've ever seen
that does that, actually. But the tabbing out does not work on
Opera, and as above, there's no way to enter the Flash object
except using Firefox + MLB.

> http://ncam.wgbh.org

This one does not allow keyboard escape.

So apparently, it is sort of possible to make Flash content
accessible under certain circumstances with one of the primary
user agents in use, and I take back my statement that it is de
facto impossible. It is possible for programmers to write Flash
in such a way that you can satisfy WCAG 2.1.2, and all of about
three programmers seem to have figured out how to do it. Sort of.

-Deborah

From: Andrew Kirkpatrick
Date: Mon, Nov 15 2010 10:09AM
Subject: Re: Technical explanation on how Flash interupts screen readers
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Thanks for the clarification Deborah. I expect now that we have techniques for WCAG 2.0 at the W3C site that include mention of this that we'll see more use of techniques like what the MLB uses. See http://www.w3.org/TR/WCAG20-TECHS/FLASH17.html for the specific technique...

Thanks,
AWK

Andrew Kirkpatrick
Group Product Manager, Accessibility
Adobe Systems

= EMAIL ADDRESS REMOVED =
http://twitter.com/awkawk
http://blogs.adobe.com/accessibility