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Re: Is aria-hidden supposed to only hide content for screen readers/assistive technology, or is it supposed to hide content altogether?

for

From: Steve Faulkner
Date: Dec 27, 2012 9:46AM

Responding briefly as I am doing so via mobile.

Unclear where the confusion about how aria-hidden comes from.

My understanding is:

Aria-hidden does not and is not defined to affect the visual display of content.

What is designed to do and what it does in browsers that implement it is to remove content in the subtree of an element (with aria-hidden) from the accessible tree representation of the HTML DOM. It does not remove anything from the DOM itself or change the display properties of content in the DOM.

The result is that any Assistive technology that uses the accessible tree to convey a representation of what is in the DOM will not report content flagged with aria-hidden as its not in the accessible tree.

Regards

SteveF

On 27 Dec 2012, at 15:37, "Birkir R. Gunnarsson" < <EMAIL REMOVED> > wrote:

> I agree. There are reasons for hiding content from screen readers that
> still appears visually (basically the equivalent of an empty alt tag
> on an image). I hope that aria-hidden will be defined that way for
> future updates or documentation, after all, doesn't HTML5 have a
> hidden property that will work exactly like aria-hidden, except it
> works for all users, not just screen readers or assistive technology?
> I can see the programming advantage of using a simple property like
> hidden over CSS classes, that's definite. But it does not meet the
> needs discussed here of hiding content from users when it not only
> does not add to the information presented by the page, but actually
> disrupts the users so that they are unable to view the content of the
> page.
> Cheers
> -B
>
> On 12/27/12, Jason Megginson < <EMAIL REMOVED> > wrote:
>> It is unfortunate that there is no clear consensus or documentation on
>> this property because in my opinion it is a powerful property that should
>> be used to hide information from screen readers while retaining
>> information visually. There is no need for aria-hidden to hide content
>> that is visually hidden from sighted users; leave that to CSS visibility
>> and/or display properites.
>>
>> I too will add another use case in favor of implementing aria-hidden to
>> "hide" content from screen readers even though the content is active in
>> the DOM:
>>
>> Aria-hidden is useful for providing gracefully degrading solutions to
>> ensure content can work with and without ARIA supported user agents.
>>
>> Consider the following simplified example:
>> <a href="#someURL" aria-haspopup="true" onblur="hidePopUp()"
>> onfocus="showPopUp()">Information
>> <span style="position:absolute; left:-400px" aria-hidden="true">
>> Contains Pop-up </span>
>> </div>
>>
>> The concept is that when ARIA and aria-hidden is supported, it will ignore
>> the off-screen positioned text to avoid double speaking by screen readers.
>> However, if user (a combination of) agents do not support ARIA, it will
>> read the off-screen text.
>>
>> Finally, HTML5 has a global attribute hidden="hidden" which is not
>> supported by IE (at this time) and it hides content from everyone. So
>> arIa-hidden should be used (and in my opinion formally proposed) to hide
>> on-screen content from screen readers. Aria-hidden is the closest thing
>> web developers have to the .silent and .forceSimple (accessibility)
>> properties of Flash and Flex and as Bryan noted earlier, it can
>> tremendously add enhanced usability when modal dialog windows are used.
>>
>> Jason Megginson
>> SSB BART Group
>> 703-637-8964 (o)
>> 703-244-7755 (c)
>>
>>