- From: Fred Esch <fesch@us.ibm.com>
- Date: Thu, 21 May 2015 07:56:57 -0400
- To: <public-svg-a11y@w3.org>
- Message-ID: <OF98BAF1ED.AB581C96-ON85257E4C.0040FB81-85257E4C.0041A3C3@us.ibm.com>
I don't see a problem with adding mappings for 1.1. But I would only want to add mappings that we would not want to remove or replace later. I like icon, but don't know if I would want to keep the rest in 2.0. We are being told that any roles we create in a graphics extension must extend something in core ARIA. I am not sure I agree with that. But I would like us to build a usable taxonomy rather than address annoyances that result from a mapping to existing ARIA. We can talk about this tomorrow. Regards, Fred Fred Esch Accessibility, Watson Innovations AARB Complex Visualization Working Group Chair W3C SVG Accessibility Task Force IBM Watson From: Amelia Bellamy-Royds <amelia.bellamy.royds@gmail.com> To: public-svg-a11y@w3.org Date: 05/20/2015 10:44 PM Subject: ARIA roles for graphics When reviewing the accessibility API mappings, I was once again struck by how useless the repeated "group" role is. I would really like to push forward with a basic set of graphics roles. Yes, our long-term goal is to come up with a nuanced taxonomy for describing the semantic meaning of charts, maps, and so on. But in the short term, can we decide on some roles for simple graphics, that we can present to the ARIA group for inclusion in ARIA 1.1? And equally importantly, that we can use as the default ARIA roles in the SVG API mappings document. Now, I know that adding new ARIA roles does not necessarily mean new API mappings -- but it gives a nudge in the right direction to the people behind the APIs. And, since the complete role string is available to accessibility tools even when it isn't mapped, it does make a little extra information available if anyone wants to use it. To recap the roles currently available for graphics, and their limitations: img Should be used only when this element and all child content forms a single image. Currently used for everything from simple icons to photographs to complex charts and maps (although hopefully not SVG charts and maps). Child content (if not used for the name/description) is assumed presentational and ignored. Therefore, img is not useful for structured graphics with meaningful parts. complementary, region, article Possible choices for labelling a figure (as a whole) if you want the component parts to still be accessible. Do not convey the idea that the content is graphical. text (new in ARIA 1.1) Complex content that should be treated as plain text with a value equal to the accessible name. Good if the graphic directly represents text, or can be replaced with a few words of text without loss of meaning, but not useful for other cases. group Conveys a structure, without specifying what it is or giving it any great importance. Doesn't have any semantic meaning beyond that. Is nonetheless what we've been using as the default mapping because it is the only role that doesn't convey incorrect semantics. The following roles I think would cover most basic graphics. In combination with proper use of other ARIA attributes (such as labelled by and flow to) they could greatly enhance the ability to describe infographics and labelled diagrams. graphic Complex visual content with a meaningful structure to it. The component parts may be interactive. A large graphic can contain component graphics so long as they still meet the criteria. This would be the default role for <svg> and <g> elements that meet the criteria for inclusion in the accessibility tree. The fallback role would either be group or region depending on how significant the graphic is. figure A graphic that is also a complementary section of the document, and should be included in the table of contents. The fallback role would be complementary. icon A graphical element which conveys a simple concept or category using a symbolic image. Differs from an image in that a short name is all that is expected; a detailed description of the visual representation is not required to convey the meaning of the icon. Children are presentational -- an icon is an atomic element. It should never have component parts with interactivity of their own descriptions -- use "graphic" instead. The fallback role would be img. This could be the default role for <use>, so that authors would have to explicitly over-ride the role if they wanted the browser to include the cloned content in the accessibility tree. shape A basic geometric shape. The main purpose of this role, as distinct from img or icon, is so that accessibility tools can communicate what type of shape it is. A new ARIA property would allow the author to convey the shape type separately from the label and description. For example, in a flow chart, the shape of nodes often conveys meaning, but you don't want to repeat that in the label, which should focus on the substantive information. Children are presentational. The fallback role would be img. This would be the default for all the basic SVG shapes if they met the criteria for inclusion in the accessibility tree. All the standard SVG shapes except path would have default shape-type descriptions that the browser should localize by default. You could also use the shape role on a group if that group represented a single graphical element (e.g., if it contained a basic shape plus its visible label, or a shape that has been duplicated and layered for graphical effect). If we can agree on a simple schema such as this, hopefully we can get it into ARIA 1.1 -- and into implementations -- while we are still working on the more complex charts taxonomy. Best, Amelia BR
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Received on Thursday, 21 May 2015 11:57:29 UTC