[Accessibility] Accessibility Digest, Vol 9, Issue 9

[Nolan Darilek]

On 04/01/2010 04:01 PM, Barbeau, Sean wrote:
> Nolan and Alex,
> I'd be very interested in being part of the conversation as well.  Our research group developed what is essentially a public transportation navigation application (i.e. the Travel Assistance Device (TAD)) that tells a person when to get off the bus using the GPS embedded in the phone, and we'd like to learn how we can make the application more friendly for individuals with visual impairments.  A few articles on TAD are here, if you're interested:
> http://www.locationaware.usf.edu/research-and-development/travel-assistance-device/tad-in-the-news/
>
>    

Cool.

Well, thus far all we've really talked about is i18n. I can localize 
Hermes, but at the moment it hasn't been much of a priority because I've 
wanted to get something working before making it localizable. The 
problems of describing a given node in natural language are complex 
enough without factoring in i18n. :)
> Nolan,
> Are you using the W3C GeoLocation API for location info?
> http://dev.w3.org/geo/api/spec-source.html
>
>    

Yes.

> If so, I believe this is supported by most recent Blackberries:
> http://docs.blackberry.com/en/developers/deliverables/11844/Support_for_Gears_APIs_738961_11.jsp
>
> And it is definitely supported by all Android devices version 2.0 and higher:
> http://developer.android.com/sdk/android-2.0-highlights.html
>
>    
And the iPhone as well, I believe, not to mention on Firefox, in which I 
do my testing.

> I think some of the AJAX might be what gives you trouble.  Based on my experience (mostly in mobile apps, not web programming), usually if something works on a desktop it doesn't work on a mobile without some tweaking.  I

That may very well cause issues. I'm hoping that the Google developers 
will implement ARIA support in whatever browser access they're cooking 
up, and am uncertain if any sort of live updates are spoken on the 
iPhone. If neither happens, there's no reason that I can't create a REST 
API and just go the native app route. I've put some thought into this 
already, though honestly I do hope that the HTML route can work.

> tried to load the site from a HTC Hero with Android that I have, but the site was down when I tried.  I'll try again later when its back up.
>
>    

Oh, that might have been you then. :) My drive started getting thrashed 
and the database process was at ~2G. I looked at the web server logs and 
saw a bunch of inbound requests, so I pulled the plug for a bit to throw 
in a fix.

I've never used the app on a mobile device, so wasn't sure how it would 
handle position updates. Basically, I didn't know if the API sent 
updates as they happened or did any sort of client-side rate limiting. 
Thanks to you, I think that I now have my answer. ;)

Feel free to try again. I'm now rate limiting to one update every five 
seconds in the app, and am storing the latest unprocessed update and 
replaying it when the timer expires. This should do the trick and keep 
the app from exploding again while always delivering up-to-date position 
data.