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Canvas Accessibility Next Steps

From: Richard Schwerdtfeger <schwer@us.ibm.com>
Date: Mon, 25 Jan 2010 15:23:57 -0600
To: public-canvas-api@w3.org, public-html-request@w3.org
Message-ID: <OF2E293D08.C243E4F1-ON862576B6.00744302-862576B6.00758CA1@us.ibm.com>

The canvas accessibility SC determined the following today:

1. It is unavoidable that we must have an element that delineates the
shadow DOM within Canvas. We decided to call this the <accessible> tag.
Over time, canvas libraries can start including support for it.

2. After discussions with other working group members it was agreed that we
needed to stay with support for fallback content and that defining
alternative media elements would create additional complexity.

3. Rather than defining alternative media elements for inclusion within the
shadow DOM we will define a collection of ARIA properties that describe the
capabilities of content in the HTML 5 DOM which can be mapped to new CSS
Media queries we define. This is slightly different from Maciej's earlier
post, but in the spirit of it. Maciej had suggested using id with
accessibility specific names however the group felt that because ids are
not unique that we needed to define corrsponding HTML 5 meta data
attributes for this purpose.

4. The new ARIA attributes for media types and media properties would be
based on Access For All (A4A) Properties from the IMS Global Learning
Consortium. We don't have to call them "ARIA" attributes but they do need
to be unique. We could call them A4A properties as well. They could also be
used to choose the fallback content if necessary. With these, a user can
define their own style sheet and apply it to a page. Also web
intermediaries could do the same based on user preferences.

Frank Olivier is going to provide a working example of 1. Jon Gunderson
will provide a working example of 3 and I work on defining the actual ARIA
or A4A attributes and work with Jon on integrating these with his example.

Feedback is welcome.

Thank you,


Rich Schwerdtfeger
Distinguished Engineer, SWG Accessibility Architect/Strategist
Received on Monday, 25 January 2010 21:24:36 UTC

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