This is an archived snapshot of W3C's public bugzilla bug tracker, decommissioned in April 2019. Please see the home page for more details.

Bug 8441 - Change event trimming
Summary: Change event trimming
Status: RESOLVED FIXED
Alias: None
Product: ARIA
Classification: Unclassified
Component: Core AAM (show other bugs)
Version: 1.0
Hardware: PC Windows XP
: P1 normal
Target Milestone: ---
Assignee: Cynthia Shelly
QA Contact: ARIA UA Implementors
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2009-12-04 21:27 UTC by Andi Snow-Weaver
Modified: 2010-11-11 22:23 UTC (History)
1 user (show)

See Also:


Attachments

Description Andi Snow-Weaver 2009-12-04 21:27:36 UTC
In the State and Property Change Events section, it says:
 
For simplicity and performance the user agent MAY trim out change events for state or property changes that assistive technologies typically ignore.
 
From Cynthia: I think this doc should provide more detail here.  What events do we think are typically ignored to trigger this statement being present?

Assigning this to David for his perspective.
Comment 1 David Bolter 2010-02-16 15:43:34 UTC
I don't think we can be exhaustive here but one example might be events that are happening on an unfocused browser window.

Maybe we could leave this section out or say something like "when filtering/throttling events browser developers should strive to do this in an interoperable way."
Comment 2 Andi Snow-Weaver 2010-03-02 15:33:57 UTC
Leave this text in and add the example David provided. 

Cynthia to check with the narrator team and provide a second example.
Comment 3 Andi Snow-Weaver 2010-04-21 20:50:46 UTC
Added the example of events in an unfocused window. 

Assigning to Cynthia to check with the narrator team and provide a second example.
Comment 4 David Bolter 2010-11-11 15:22:46 UTC
Another example is if there is a node removal, followed by the parent node removal... you could just create an event on the topmost parent removal.
Comment 5 Andi Snow-Weaver 2010-11-11 22:23:15 UTC
Modified from:

For simplicity and performance the user agent MAY trim out change events for state or property changes that assistive technologies typically ignore, such as events that are happening in a window that does not currently have focus. 

to:

To improve performance on APIs that use a broadcast event mechanism, the user agent may trim out change events for state or property changes that assistive technologies typically ignore, such as events that are happening in a window that does not currently have focus. On other APIs that use a subscription-based event mechanism, user agents should allow assistive technologies to subscribe to any event, and should not trim events.