RE: New SC relating to notifications of content change (was Re: Some thinking around the orientation discussion)



>-----Original Message-----
>From: Patrick H. Lauke [mailto:redux@splintered.co.uk]
>Sent: Friday, May 06, 2016 4:22 AM
>
>I think WCAG currently lacks an SC that essentially says something along the
>lines of "When content/structure/functionality is changed dynamically (either
>automatically or as a result of a user interaction), ensure that this change is
>conveyed to the user" (probably single or double A).


This is an interesting idea. My initial reaction was to propose that it should say "can be programmatically determined", but it isn't clear to me under what circumstances such a criterion would fail to be satisfied. Whenever elements which are reflected in the tree constructed for an accessibility API are updated, the change should be propagated to the API automatically by the user agent.

What ARIA live regions achieve is to notify the assistive technology that the user should be informed of the change, and I think this is closer to what is needed. However, not all changes merit this treatment. For example, a screen reader user could be overwhelmed and distracted by rapidly updating content, such as high-volume communication in a text-based chat application, especially while trying to write or to review a message. I suspect the same is true of rapidly updating share market prices, social network messages, sports scores and similar examples that have been discussed over the years, where the user is trying to interact with other content in the same Web application.

Thus it seems clear that the challenge lies in defining which changes ought to be flagged as significant enough to be conveyed to the user via an assistive technology. Requiring them actually to be conveyed (rather than designated as important) is asking too much, since this can depend on factors beyond the control of the content author, such as whether an AT is in use and what it supports. However, the author can certainly use ARIA, focus changes and possibly other techniques to influence what is drawn to the user's attention.

There are two open questions here: which changes should be identified as important enough to be conveyed to the user, and what exactly is the content author required to do? One could require, for example, that such changes can be programmatically distinguished from other changes occurring in the content, so that the assistive technology can determine which changes to attend to. This seems closer to what is wanted, but it still doesn't clearly delineate the relevant category of changes.


________________________________

This e-mail and any files transmitted with it may contain privileged or confidential information. It is solely for use by the individual for whom it is intended, even if addressed incorrectly. If you received this e-mail in error, please notify the sender; do not disclose, copy, distribute, or take any action in reliance on the contents of this information; and delete it from your system. Any other use of this e-mail is prohibited.


Thank you for your compliance.

________________________________

Received on Friday, 6 May 2016 13:24:18 UTC