Re: Alt content [ was: “Adaptive Image Element Proposal”, now off HTML WG list ]

Hi Mat and all,

> What I’d like to do here is get your thoughts, as authors, on the following:
>
> 1) Duplicating the `alt` attribute on both `picture` and the fallback `img`
> 2) `alt` specified on fallback `img`, using `aria-labelledby` on `picture`
> to reference the ID of the fallback `img`
>
> If you were marking up a page either by hand or by way through integration
> with a CMS, which approach feels more intuitive to you? Which would you
> prefer?

1. Because it is far less complicated. With aria-labelledby the
capacity for author error is great. Likely errors include but are not
limited to:

* Getting ID naming rules wrong.
* Logical errors, such as circular references.
* Accidentally deleting the label leaving aria-labelledby referencing
a non-existent ID.
* Accidentally overwriting the label with unrelated content leaving
aria-labelledby  pointing to a label that is not a label of the given
element.

In addition the Introduction to ARIA clearly states,
"WAI-ARIA is intended to be used as a supplement for native language
semantics, not a replacement. When the host language provides a
feature that provides equivalent accessibility to the WAI-ARIA
feature, use the host language feature." [1]

The Protocols and Formats (PF) Working Group's Charter states,
"Note that WAI-ARIA is intended to be a bridging technology. It is
expected that, over time, host languages will evolve to provide
semantics for objects that currently can only be declared with
WAI-ARIA." [2]

This was reinforced by Al Gilman, prior PF Chair, on behalf of that
Working Group,
"The working group likes the idea of having built in semantics in HTML
and in particular would prefer to have common document elements, such
as widgets built in to the markup. This reduces download size and the
effort required to make a web page accessible. For these reasons, we
would promote the use of such markup over the ARIA approach." [3]

The idea was that native mechanisms enrich the vocabulary of the
language, thus rendering ARIA increasingly unnecessary.

As Derek Featherstone has stated, "ARIA is designed to provide
accessibility at a technical level - what you might call 'programmatic
accessibility' - where it doesn't already exist". [4]

alt exists.

A significant goal of WAI-ARIA is to:
"help stimulate the emergence of more semantic and accessible markup.
When native semantics for a given feature become available, it is
appropriate for authors to use the native feature and stop using
WAI-ARIA for that feature." [5]

Henri Sivonen has stated,
"the whole point of ARIA is to make semantic abuse accessible as an
afterthought." [6]

Ian Hickson:
"is not intended for use by authors who are trying to convey the very
semantics that HTML can already convey." [7]

I disagree with Henri and Ian on many HTML topics but on this I agree.

Best Regards,
Laura

[1] http://www.w3.org/TR/wai-aria/introduction
[2] http://www.w3.org/WAI/PF/charter201006
[3] http://lists.w3.org/Archives/Public/public-html/2007Jul/0903.html
[4] http://www.alistapart.com/articles/aria-and-progressive-enhancement/
[5] http://www.w3.org/TR/wai-aria/introduction#co-evolution
[6] https://www.w3.org/Bugs/Public/show_bug.cgi?id=13265#c1
[7] https://www.w3.org/Bugs/Public/show_bug.cgi?id=13265#c3

-- 
Laura L. Carlson

Received on Thursday, 30 August 2012 19:48:42 UTC