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Next events meeting: 17 Jan 2002 @ 4pm ET

From: Ian B. Jacobs <ij@w3.org>
Date: Fri, 04 Jan 2002 12:40:19 -0500
Message-ID: <3C35E903.B9D5BF36@w3.org>
To: rayw@netscape.com, plh@w3.org, lehors@us.ibm.com, shane@aptest.com, gleng@freedomscientific.com, jongund@uiuc.edu, charles@w3.org, asgilman@iamdigex.net
CC: w3c-wai-ua@w3.org
Hello,

Thank you to all who attended the 20 Dec 2001 UAWG teleconf [1]
on events, the DOM, and UA requirements. I found it very helpful.
The next meeting to resolve open issues will be 17 Jan 2002 @ 4pm ET
(telephone: +1-617-252-1038) for up to 90 minutes.

At the 20 December meeting, we reviewed a summary [2] of what
seemed to be the open issues. Here's the latest summary of where
I think we are (and what we have to address on 20 Dec). 

If I've made technical errors below, please send corrections.
Also, please indicate whether there are other issues that I
have omitted.

Thank you,

 - Ian

1) What's the best way to ensure that assistive technologies
   can identify and trigger event handlers?

Agreement: A boolean function will suffice; we don't need the list
           of event handlers.

Agreement: We do not need to fire handlers one at a time; it suffices
           to be able to fire all handlers for a given event type.

Open: Should there be one or two boolean functions for querying
      a node N:
  
  a) Does N itself have a handler for event type E?

  b) Is there *any* observer with a handler for event type E
     that will be called if E occurs at N?

     Agreement: In (b), because an observer may stop the capture
     or bubbling processing phases, node N's handlers may never
     be invoked if E occurs at N. We may know some behavior 
     in advance from markup (cf. XML events draft [3], 'propagate'
     attribute). 

  Ray Whitmer has argued that the granularity of the query and
  the granularity of the dispatch should be the same. If version
  (a) of the query is chosen, then the query granularity will be
  one node only, but a dispatch will cause processing by other
  nodes as well. Thus (if I understand it), Ray prefers version
  (b) and asked us to provide a use case for version (a): when
  would an AT need to know that there's a handler on a given
  node N, even if that node's handlers might not be triggered
  (if an observer stops the bubble or capture process).

Todo: The WAI groups need to provide a use case of when it's useful 
  to know that an event handler was declared on the current node 
  and not an ancestor.

2) What's the best place to describe the semantics of
   author-specified behaviors?

We have not progressed much on this issue. However, there is
some sense that this is more of a format issue than a DOM issue.

Ray has stated that it doesn't make sense to be able to
specify descriptions on a per-handler basis if you can't
activate handlers individually. 

Question: Would it be useful for the DOM to provide all
descriptions of all handlers for a given event type? Or
should we specify instead (one or more) descriptions for an 
event type (rather than handler)?

Please indicate what other questions WAI or the DOM WG or the
HTML WG should answer.
	
[1] http://lists.w3.org/Archives/Public/w3c-wai-ua/2001OctDec/0135
[2] http://lists.w3.org/Archives/Public/w3c-wai-ua/2001OctDec/0132
[3] http://www.w3.org/TR/xml-events/
-- 
Ian Jacobs (ij@w3.org)   http://www.w3.org/People/Jacobs
Tel:                     +1 718 260-9447
Received on Friday, 4 January 2002 12:40:32 GMT

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