Executive Summary: FlashAid enables Ajax/JavaScript to find out if a user's screen reader is currently communicating with the browser and turn off the JavaScript functionality accordingly to make their sites accessible. It only works on Internet Explorer on Windows.
And now the full story...
I just released an update to FlashAid that, well, actually makes FlashAid useful.
You can see a live demo of FlashAid here.
(FlashAid only works on Internet Explorer on Windows. Make sure you have your screen reader on before testing.)
Version 0.1, the previous release, was a proof-of-concept that I hacked together after a talk with Jeremy. All it did was pass the value of the System.capabilities.hasAccessibility property from Flash to JavaScript.
The Adobe Flash docs for System.capabilities.hasAccessibility states the following:
A Boolean value that is true if the player is running in an environment that supports communication between Flash Player and accessibility aids; false otherwise.
What the documentation should state, is:
A Boolean value that is true if the player is running in Internet Explorer on Windows.
Essentially, that's all hasAccessibility appears to show. The Flash player uses MSAA to talk to screen readers but it only works in Internet Explorer (FireFox has MSAA support but the Flash player returns false for hasAccessibility on that platform, for example.)
So, the FlashAid proof-of-concept was essentially useless (you can check for IE on Windows with one line of code in JavaScript.)
Version 1.0, though, does have an important use. It's a one trick pony that communicates the value of Flash's Accessibility.isActive property to JavaScript. This one's useful because, on Internet Explorer on Windows, it tells you whether the user's screen reader is actually communicating with the browser.
Why is this important? Because it allows Ajax developers using progressive enhancement to detect whether the user is using a screen reader and turn off the Ajax/JavaScript functionality to allow these users to access their sites and applications.
Again, keep in mind that this only works for Internet Explorer on Windows but it's still an improvement on what was previously possible.
I hope you find FlashAid v1.0 useful.
The FlashAid version 1.0 released article by Aral Balkan, unless otherwise expressly stated, is licensed under a Creative Commons Attribution-Noncommercial 2.0 UK: England License.

I remember Adobe Legal not allow other people using Flash(TM) in their products, check FlashObject(SWFObject) case.
Hi Luar,
If they have a problem with it, I’ll change it.
I blogged about my reasons for using “Flash” in the name of this: I think it does the Flash Platform good to be associated with it. It can just as easily be called AjaxAid if necessary.
[...] This post is out of date: See my post on the latest version of FlashAid (1.0) for up-to-date information. [...]
Hey Aral,
this is great. I was asking Niqui if we could build something like this, and lo, she said “Aral already had”. You rock.
I’m still tempted to make it a combination solution though, I don’t like relying on one technology to support another. I think I’m going to use SWFObject to check for Flash and if there isn’t Flash insert an off-screen AJAX warning into the DOM. If there is Flash FlashAid can deal with it.
It might be good user experience to insert something off-screen to notify the user that AJAX has been turned off and give them an option to turn it back on if they have JAWS 7.1 or Windows Eyes 5.5 .
Hey Tom,
Aral already had! :P
You can use the failure callback for this. FlashAid already uses SwfObject to embed the flashAid.swf file. If Flash doesn’t exist or is the wrong version, the failure callback will be called. You can handle this any which way you like in the failure handler.
Can you give me an example what you mean — doesn’t sound difficult to add if it’s going to be useful. I’m assuming this is for those times that JavaScript is off? (Currently, the alternate content in the flashAid div is displayed in these circumstances.)
[...] I’m glad Niqui talked about FlashAid. Aral and Jeremy did a fabulous job. I posted some comments on how I would like to see Flash Aid used already, but I look forward to seeing what the community thinks. [...]
[...] FlashAid puente Ajax/Javascript para la accesibilidad con Flash El 3d llegó a Flash para quedarse Componentes para Flex Conferencia 360 de Flex Apollo Guide para desarrolladores Flex Adobe a punto de lanzar Apollo Concurso de cliente Flex para Wordpress Concurso de Aplicaciones Móviles en Flash Lite Flash Lite para Sony Ericsson Flash Lite para PSP Algunos anuncios flasheros en el 3GSM Adobe MAX 2007 en Barcelona Chumby un juguete para geeks flashers Show us the Code [...]