ISSUE-56 Re: Tree sample code -- Member link

On 2 Sep 2008, at 8:56 AM, Aaron M Leventhal wrote:

> Here are my comments on Microsoft's tree sample:
> 1. It uses aria-level, aria-setsize and aria-posinset when it  
> doesn't need to.
> The idea is that authors only need to do that if the tree is not  
> DOM complete -- iow it's loaded dynamically. When the entire tree  
> structure is there the user agent is supposed to calculate that  
> info from the structure.
> 2. It uses <li><a/></li> constructs.
> This seems to be to allow for graceful degredation for non-ARIA  
> clients. However, it means that the tree has list, list item and  
> tree item objects mixed together, and no longer looks like a tree  
> widget to current generation ATs. Neither current ATs nor Firefox 3  
> will process the structure and automatically provide info like the  
> level, posinset and setsize.
> In general, the current implementors guide algorithm will not work  
> with this tree. So either the tree needs to change, or the impl  
> guide algorithm or both.
> What do you suggest?

We closed ISSUE-56 on 18 August because James Craig was able to
re-do the tree so that

a) it uses nesting as you would expect for sub-items
b) it requires no changes to the spec

So the center of attention should now be on the example the way James
coded it.  Comments on how that has been done are still very relevant.

In that meeting I said we still might *add* a more backward-compatible
design as well.  To the Best Practices Guide.  But so far we haven't
found a need to change the spec.

This does not address possible problems
with the Implementers Guide -- that would be new information we
didn't have on the 18th.

Will the approach in the Implementor's Guide work with James's recode?
Can it be fixed to do so?  Is there a reason based on implementation --
over and above ability to code a tree with nesting -- that suggests  
we should
have different features in the markup?


> - Aaron
> From: Cynthia Shelly <>
> To: "" <>
> Cc: George Young <>
> Date: 07/07/2008 11:21 PM
> Subject: Tree sample code
> As promised, here is a zip of the tree sample I demo’d at the face  
> to face.
> Tree.htm uses only nested unordered lists of links (with onclick  
> handlers) to achieve tree behavior.  JAWS in virtual cursor mode  
> with medium verbosity does a good job of reading the list levels.   
> Tab+enter opens and closes the tree levels.
> Ariatree.htm is the same tree, with aria markup added to the  
> links.  With virtual cursor turned off, list level information is  
> exposed to MSAA.  This was tested with IE8 beta 1 and JAWS 9.   
> There are a few bugs in what is exposed to MSAA by IE in this early  
> build, which will be fixed.
> I’ve copied George Young, who wrote the original tree, to which I  
> added ARIA for the CSUN demo.  George is the best person to work  
> with on combining this tree with any other samples that have more  
> extensive keyboard handling features.[attachment ""  
> deleted by Aaron M Leventhal/Cambridge/IBM]

Received on Tuesday, 2 September 2008 18:06:59 UTC