RE: Request for advice on <canvas> accessibility

On Fri, 10 Jul 2009, Steve Faulkner wrote:
> The discussion on IRC last night was useful 
>, in that it started 
> to grapple with the issues of providing methods to allow developers to 
> provide objects in canvas with built in interaction behaviours, 
> something they could use in their course of their development without 
> having to think about how to add accessibility.

Unfortunately that discussion only touched on the comparatively simple 
problem of keyboard focus. I agree that it was useful though. Is there an 
IRC channel where WAI members discuss similar issues? It would be really 
great to get input from the WAI members on how to address these issues.

> > Is there some way to follow the WAI's work on this? What is the 
> > process by which the WAI can provide advice on such topics?
> Discussion will occur on wai-xtech and public html lists Though I think 
> that the technical progress will come more from those such as yourself 
> who have the most expertise in engineering HTML.

To be honest I think that the accessibility expertise of the WAI group is 
far more important here than what little HTML engineering expertise I and 
others may have. In this particular instance, for example, I really have 
no idea how to truly make <canvas> accessible (short of the solution that 
is already in HTML5, which you have pointed out can best be described as a 
primitive example of "bolt on" accessibility).

I was hoping that the WAI group would be able to suggest solutions that 
are better than this; the "HTML engineering" expertise side of things has 
so far failed to find any (except for the keyboard focus issue, which is a 
relatively simple issue in comparison).

> > I'm certainly happy to look at other cases also. The main reason I 
> > suggested the HTML5 issues list graph: 
> >
> The answer to making this accessible is to provide the data in html 
> format marked up as a data table.

I've now done that; thanks for the advice. Is this really all that needs 
to be done? It's what the HTML5 spec recommends today, but I thought we 
were agreed that that was not enough, and that in fact that was an 
accessibility issue that needed resolving.

> The example i posted yesterday is not a demo 
> and provides another example of a canvas containing interactive 
> elements.

What can we provide to make this more accessible as is, without resorting 
to the bolt-on fallback page?

Ian Hickson               U+1047E                )\._.,--....,'``.    fL       U+263A                /,   _.. \   _\  ;`._ ,.
Things that are impossible just take longer.   `._.-(,_..'--(,_..'`-.;.'

Received on Friday, 10 July 2009 21:28:08 UTC