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Re: Seeking thoughts on real world application of SC 1.4.2 Audio Control on iOS

From: Gregg Vanderheiden <gv@trace.wisc.edu>
Date: Fri, 24 May 2013 00:12:18 -0400
Cc: "public-wcag2ict-tf@w3.org Force" <public-wcag2ict-tf@w3.org>
Message-Id: <99970E47-72F8-4116-89E5-DF5046D92A3B@trace.wisc.edu>
To: Peter Korn <peter.korn@oracle.com>

Hi all,

You can read all the notes and comments below -- but the bottom line is quoted here

       Good catch Peter.   I think we may need to add a sentence to the Closed Functionality Section that reads:

NOTE: If the platform has no AT, does not provide the functions of AT and does not support the use of AT with its APPS,  then the APPS will have to function as closed functionality apps and also follow the rules established for closed functionality. 


On May 23, 2013, at 1:49 PM, Peter Korn <peter.korn@oracle.com> wrote:

> Gregg,
>>> Just two quick points...
>>> I was ONLY speaking about whether and how close we were to a situation in which iOS apps (only) might be able to leverage/rely on built-in iOS and VoiceOver behavior to fulfill 1.4.2.
>> iOS  /  Voiceover does not meet 1.4.2.  
> I'm not disagreeing with this - hence the "how close" comment.  Note also the terminology.  Firefox doesn't meet 1.4.4.  An app that works with the built-in Firefox zooming feature meets 1.4.4.  That's the possible parallel I was exploring.

GV: why doesn’t firefox meet 1.4.4?   Actually I should say -- why doesn’t Firefox allow content to meet 1.4.4 ?    

>>> I'm pretty sure that the volume lowering functionality is an OS/VoiceOver-level function, ...
>> Correct.   But it doesn’t meet 1.4.2
> Again, no disagreement; the functionality is in the right direction, but not sufficient to cover all of 1.4.2 (today).

>>> ...and NOT something that is explicitly built into the podcast/music-playing app.  Given how closely integrated VoiceOver is to the platform, and its privileged status as a special application, this is certainly the way I would implement that functionality.  And perhaps a future version will extend the functionality so that complete muting is an option.
>> That still wouldn’t necessarily  do it for all iOS apps.  It would only take care of it for the VoiceOver use on the platform.    Other apps that self serve voice. 
> Ahhh!  Now we are getting somewhere interesting.  Understanding SC 1.4.2 specifies only one disability use case, as set forth in the first sentence: "Individuals who use screen reading software can find it hard to hear the speech output if there is other audio playing at the same time". 

GV:  That is an example.  but Understanding WCAG 2.0 does not override the language of the SC itself. 

> VoiceOver is the only screen reader (I'm aware of) for iOS. 

GV:  Right.  Since it is a locked system -- it is the only one possible 

> So long as the audio-generating app is compatible with VoiceOver and any volume lowering (and potential future muting) functionality, the app should be able to rely on that VoiceOver/platform functionality to address that accessibility issue, right? (acknowledging that today that functionality is insufficient to address all of 1.4.2).

GV:  Not necessarily. it only works for screen reading.  But this SC also applies to self voicing.   So lets say we have an app that self voices (not using voiceover).    It also has audio that plays for everyone in the background when you view the page.  Those who would interfere. 

> Certainly a self-voicing app that is also a self-non-speech audio-playing app would have the responsibility of lowering/muting the non-speech audio when the self-voicing functionality is running.  Is that what you were referring to?

GV:  Yep. exactlu

>  Or something else?  

> But, even then, such an app might not meet the letter of WCAG (e.g. if the self-voicing app didn't provide a feature for turning down/off the speech volume it was providing separate from the OS volume, since even the built-in speech of the app ISN'T the speech of VoiceOver and could therefore interfere with VoiceOver speech).

GV:  Right -   It would meet WCAG if it met the SC   and it wouldn’t if it didn’t.  
>> <snip>
>>> One of things I'm most concerned about is actually in the other direction - characteristics of a platform that make it difficult or perhaps even impossible for an application on that platform to meet all of WCAG A/AA. 
>> Interesting -- what are some things you see that might do this? 
> Well, this is where we start approaching the situation of "closed functionality".  Certainly at the extreme end is a platform for which there is no AT and no or insufficient built-in accessibility features to enable folks with various disabilities to have access. 

GV:  Well clearly it can't meet WCAG if there is no AT and not build in accessibility. 

> But at the other end...  
> Had AT not developed in the past decades, with analysis techniques for discerning things like columns of text and headings in the command line / text application world of DOS/UNIX/Linux, then I would suggest that those platforms lacked the ability to meet things like 1.3.1 and 1.4.2.  They lacked a means to convey structure and relationships.  They lacked a way to convey anything that is programmatically determined.

GV:  Not sure what you are saying?   Are you saying that if there wasn’t any AT then there wouldn’t be any access?  Agree.  But there is.  So...     ????

> Certainly an individual application, which has such structure internally, might be able to first define and then convey that information to AT.  That is pretty much exactly what we did with the Java platform running on Windows - conveyed structure and relationships and object information via the Java Access Bridge to AT that added support for that bridge (since at the time we started that work, Windows lacked sufficient support in the OS for such things).

GV:  Right.

> But we are then going beyond the realm of "telling an app developer how to meet SC x", and into the realm of "developing enabling mechanisms to compensate for a lack in the platform so that in the future app developers will be able to meet SC x".  And there is little an app developer may be able to do should someone want to procure an app on such a platform ahead of such development.  Except, perhaps, write the self-voicing, self-brailling, self-voice-recognizing, self... etc. etc. app.  

GV:  Right.  If you write apps for a platform that does not have access features then you need to provide them.

Or to put it more properly -- you are responsible for making your app accessible.  If the platform provides a bunch of  access functions -- then it is MUCH easier for app developers.   If not then the app developer doesn’t get those head starts.      As  a result it behooves the app developers to ask that these be in the platform (which is something that is happening now with Android --and Google is responding.   

Note also that every platform is software in itself so it needs to provide those capabilities for itself -- and therefore extending it to the apps is a logical thing to do. 

> In fact, that becomes another WCAG2ICT question...  Exactly what AT features must an non-Web app build into itself in order to satisfy all of the SCs?

GV:  It doesn’t need to build in any specific features.  It has to meet the SC.  And it needs to do whatever it takes to do so.    There may be different ways to do this. 

>   We have our Closed Functionality list, but we have essentially said it is beyond the scope of WCAG2ICT to define this. 

GV:  Yes - if the app is going to be self voicing etc - and not rely on AT then it would probably follow the closed functionality provisions.

> So... if the platform lacks, say, a screen reader, then how can an app be "accessibility supported" ever?  Seems to me it can't, and it falls to whatever regulatory structure incorporates WCAG for non-Web software to describe that case.  Full stop.

GV:  Correct.   If there is no AT then you have the equivalent of a closed functionality App - since it can't rely on AT if there isn't any.    

THis is an interesting point.  Essentially -- if there IS NO AT for a platform, and it doesn’t provide accessibility support itself (e.g. the functions of AT) then it would essentially have to function as a closed functionality product.    

Do we add a sentence to the Closed Functionality Section that reads:

NOTE: If the platform has no AT, does not provide the functions of AT and does not support the use of AT with its APPS then the APPS will all have to function as closed functionality apps and follow the rules established for closed functionality. 

>>> If an agency decides to deploy such a platform, there may be little to nothing an application vendor can do to offer an application that meets all of WCAG A/AA on that platform.
>> Well, they can always just build all of the accessibility in.    and for some platforms that is needed   (but that is not a good situation or platform). 
>>>   And unlike the web (where an agency might install a web user agent from "Jim's Storm Door and browser company" that doesn't magnificent content or expose a DOM or work with any AT), platform-specific binaries don't have the ability to claim "accessibility supported" by noting other platforms that their app is accessible on.  Because "platform-specific" means there is only one platform that can be used to evaluate it...
>> OK.     Can you give me some examples of this?   There are lots of platforms that don't provide some or many access features.  Apps need to provide them directly on these platforms. (there are 10s of thousands of kiosks that do this).    
>> this is best thought of as    "the app is responsible to provide all access to the app -- but if the operating system (or browser or other intermediate platform) can be relied up to provide some of the access features for the app -- then then app can use those to meet its requirements.   but otherwise it is responsible. 
> Yes, but...  As I noted above, handling such a situation seems to be beyond the scope of WCAG itself.  WCAG was written for an environment for which there was AT and user agents and platforms that had accessibility services, etc. etc.  When WCAG is applied to native, non-Web apps running on a platform without these things, it seems to me WCAG itself falls silent on some key issues and we have to look to other parts of any regulatory framework that is incorporating and applying WCAG to handle the situation.

GV:  Agree.    I think we may need a note like the one above. 

Good catch Peter. 

> Peter
> -- 
> <oracle_sig_logo.gif>
> Peter Korn | Accessibility Principal
> Phone: +1 650 5069522 
> 500 Oracle Parkway | Redwood City, CA 94065 
> <green-for-email-sig_0.gif> Oracle is committed to developing practices and products that help protect the environment

Received on Friday, 24 May 2013 04:13:22 UTC

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