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Re: Does filtering count as "change of context" asregardsWCAG 3.2.2


From: Matt King
Date: Jun 16, 2017 1:15PM

I completely agree with Tim.

-----Original Message-----
From: WebAIM-Forum [mailto: <EMAIL REMOVED> ] On Behalf Of Tim Harshbarger
Sent: Friday, June 16, 2017 10:25 AM
To: WebAIM Discussion List < <EMAIL REMOVED> >
Subject: Re: [WebAIM] Does filtering count as "change of context" as regards WCAG 3.2.2

I think the key in this situation is whether or not the change in content is a change in context.

When you read further on this SC, it talks about context. It also states that a change of contents on the page may or may not represent a change of context.

My own opinion is that applying the filtering options does not change the context. However, adding a live region to report on how many results remain after applying a filter would be a really great idea.

I know I would find it useful to receive immediate feedback regarding whether or not the filter I just applied left me with 5 items or 0 items. When that feature isn't present, it doesn't necessarily prevent me from using filtering or using the page, but it means I do have to try to figure out what results remain. Being told immediately how many results remain would make it easier to know if I had applied too many filters or not enough.
-----Original Message-----
From: WebAIM-Forum [mailto: <EMAIL REMOVED> ] On Behalf Of Robert Fentress
Sent: Friday, June 16, 2017 11:47 AM
To: WebAIM Discussion List < <EMAIL REMOVED> >
Subject: [WebAIM] Does filtering count as "change of context" as regards WCAG 3.2.2

A pattern you see more and more is when a user changes the setting of an interface component in a web page, such as a select element, checkbox or text field, and it dynamically filters the results displayed in the main content area of the page. Does WCAG 3.2.2 <https://www.w3.org/TR/UNDERSTANDING-WCAG20/consistent-behavior-unpredictable-change.html#context-changedef>
require, then, that the user be informed that making such changes will have this effect before he or she begins interacting with the control? That criteria as is as follows, by the way:

*On Input:* Changing the setting of any user interface component does not automatically cause a change of context unless the user has been advised of the behavior before using the component.

If the user must be informed, is it sufficient to make a blanket statement somewhere on the page before these controls that says something like "changing the value of these controls dynamically filters the results below." For web applications, would it be sufficient to provide instructions in the documentation. Or must the control be semantically associated with the in-page instructions, by doing something like adding aria-describedby to the control and pointing to the id of the instructions? Would doing so make things too verbose? My justification for making that explicit association is that users may just tab to the control and miss the instructions, otherwise.

Also, I like the idea of using a polite ARIA live region to announce the number of results returned in a non-verbose way, like "5 results." Anybody think that is bad practice? Just seems like that is a useful affordance that more closely approximates the experience of sighted users. What do you think?


Rob Fentress
Senior Accessibility Solutions Designer
Assistive Technologies at Virginia Tech
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