W3C home > Mailing lists > Public > public-html@w3.org > January 2010

Re: Fw: Proposal: Canvas accessibility and a media querries approach for alternative content (Action Item 6 in the HTML Accessibility Task Force)

From: Ian Hickson <ian@hixie.ch>
Date: Fri, 8 Jan 2010 22:30:21 +0000 (UTC)
To: Richard Schwerdtfeger <schwer@us.ibm.com>
Cc: "public-canvas-api@w3.org" <public-canvas-api@w3.org>, public-html@w3.org
Message-ID: <Pine.LNX.4.62.1001082224590.17515@hixie.dreamhostps.com>
On Fri, 8 Jan 2010, Richard Schwerdtfeger wrote:
> > >
> > > It is not like XBL 2 as the XBL 2 shadow tree cannot be accessed in 
> > > the browser DOM.
> >
> > It _is_ exposed to script, if that's what you mean.
>
> As I understood it, and I may be wrong, the XBL shadow DOM was not part 
> of the actual web page DOM ... I could walk the main DOM tree to access 
> these DOM elements in script. If it is then yes it is like the XBL 
> shadow DOM and we should stay with the term shadow DOM.

The XBL2 Shadow Tree is exposed on the shadowTree IDL attribute on the 
DOM of the bound element.


> Would a DOM inspector get the subtree DOM?

That depends on the DOM inspector. There's no reason why one shouldn't.


> > From your description it just sounds like the regular DOM. Maybe 
> > "fallback subtree DOM", if you feel the need to qualify the term.
>
> Yes, I feel we need to qualify this.

Fair enough. I strongly encourage you to use the term "fallback subtree 
DOM" or something along those lines, as IMHO it is more accurate than 
"shadow DOM".


> If we were to expand this to the entire page that would be great but we 
> also need the ability to replace specific components of the page with 
> alternatives. For example, parts of the page may meet the user's need as 
> is where other parts do not.

Could you give a concrete example where there is alternative content that 
could not be given in the <canvas> element's fallback content and would 
not be appropriate for all users, such that you would want to actively 
hide it from some users? I'm having difficulty imagining what this case 
would be. The examples I've seen so far, and the user cases I studied when 
designing the <canvas> accessibility story several years ago, all fall 
into the two categories of either (a) appropriate for <canvas> fallback 
contents or (b) suitable for all users.

-- 
Ian Hickson               U+1047E                )\._.,--....,'``.    fL
http://ln.hixie.ch/       U+263A                /,   _.. \   _\  ;`._ ,.
Things that are impossible just take longer.   `._.-(,_..'--(,_..'`-.;.'
Received on Friday, 8 January 2010 22:30:50 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Wednesday, 9 May 2012 00:16:57 GMT