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Re: ACTION: PP to Proposal on ways User Agents could use live regions.

From: Charles L. Chen <clc@clcworld.net>
Date: Thu, 26 Jul 2007 21:30:11 -0500
Message-ID: <46A958B3.1000100@clcworld.net>
To: David Poehlman <david.poehlman@handsontechnologeyes.com>
CC: Jim Allan <jimallan@tsbvi.edu>, wai-xtech@w3.org, pparent@us.ibm.com

Already spoke to Jim on the phone and will attend the UA meeting next 
Thursday to discuss this.

-Charles
aka, the author of Fire Vox

>The author of firevox might be able to help.
>
>----- Original Message ----- 
>From: "Jim Allan" <jimallan@tsbvi.edu>
>To: <wai-xtech@w3.org>
>Cc: <pparent@us.ibm.com>
>Sent: Thursday, July 26, 2007 4:30 PM
>Subject: FW: ACTION: PP to Proposal on ways User Agents could use live 
>regions.
>
>
>Hi,
>Live regions were discussed during several  User Agent Working Group
>meetings. There is a proposal for rewriting a checkpoint.  A reality check
>is needed on the assumptions and what the expected UA (UA+AT) behavior
>should be for live region markup. See the message below.
>
>Any thoughts appreciated.
>
>Jim Allan
>  -----Original Message-----
>  From: w3c-wai-ua-request@w3.org [mailto:w3c-wai-ua-request@w3.org]On
>Behalf Of Peter Parente
>  Sent: Thursday, July 26, 2007 9:24 AM
>  To: Jan Richards
>  Cc: WAU-ua; w3c-wai-ua-request@w3.org
>  Subject: ACTION: PP to Proposal on ways User Agents could use live
>regions.
>
>
>  This action item concerns checkpoint 3.5: Toggle automatic content
>retrieval and its application to dynamic regions within a page (e.g. AJAX).
>I indicated on the wiki that user agents may be able to respect this
>guideline for partial page refreshes if the page contains appropriate live
>region markup.  (wiki checkpoint 3.5
>http://www.w3.org/WAI/UA/wiki/ConfigToNotRender)
>
>  We must answer two questions before we can decide how to rewrite this
>guideline. I discuss them in detail below. At the end of the email, I take a
>crack at reformulating checkpoint 3.5 under a few assumptions.
>
>  1) What "part" of the UA should we hold responsible for this guideline?
>
>  So far, it has been implied that the AT is responsible for deciding how
>live regions are presented. For instance, if a screen reader is busy reading
>the content of a page and an event occurs outside the point of regard in a
>"rude" live region, whether that change is announced or not is determined by
>the screen reader settings (e.g. "Rude regions interrupt? [yes/no]").
>However, use of live region information is not limited to ATs. For instance,
>the browser could conceivably have an inherent setting that controls whether
>or not changes to the DOM are allowed. Essentially, this toggle would allow
>the user to make parts of the DOM "read-only" on demand. In both cases, the
>granularity can range from a single live region, to live regions with
>certain properties, to all live regions on a page.
>
>  We need the following information from browser developers before we know
>if this technique is feasible or not.
>
>  a) Is it possible to implement a "read-only DOM" setting without breaking
>existing Web apps?
>  b) Is the base browser the right place to implement such a setting?
>  c) Is it possible to implement in a browser extension?
>
>  2) Is "retrieval" what we should really be toggling?
>
>  This question is about the intention of the guideline as compared with the
>language used. Relying on live region markup to block changes to the DOM is
>a technique applied after content has been retrieved. In fact, it can only
>be applied after content has been fetched. Beforehand, the browser has no
>concept of the purpose of the fetch. For instance, some Javascript code
>might send a message to the server and receive a response that is never
>rendered for the user. On the other hand, the Javascript code may intend to
>write the response into the DOM for the user. But until that code actually
>touches the DOM API, the UA has no way of determining where in the page it
>will appear (i.e. in what live region, not in a live region, not in a
>visible element).
>
>  I think the true intention of this checkpoint is to "toggle automatic
>content changes." In some cases, such as a full page refresh, blocking
>content retrieval may be the proper technique. In the case of AJAX, however,
>it is not, nor should it be implied.
>
>  If we assume that implementing read-only DOM is possible and retrieval is
>more of a technique than a requirement, we might rewrite the guideline as
>follows:
>
>  3.5 Toggle automatic content updates
>
>  1. Allow configuration so that the user agent only replaces existing page
>content on explicit user request.
>
>  Normative inclusions and exclusions
>
>  1. When the user chooses not to update content, the user agent may ignore
>that content; buffering is not required for later rendering.
>  2. When automatic content updates are disabled, a user agent may choose to
>avoid retrieving content that it will ultimately not render. The browser
>should take care not to block fetches that will not render in the UI.
>  3. This checkpoint only applies when the user agent, not the server,
>automatically initiates a content update.
>
>  (I suggest we remove the second part of 3.5 about redirects. Why don't
>these count?)
>
>  Notes
>
>  (Can stay the same.)
>
>  Techniques
>
>  (This is where notes about blocking page refreshes, blocking redirects,
>and making live regions read-only can go.)
>
>  Peter Parente
>  pparent@us.ibm.com
>  Tie: 526-2346
>  IBM: 919-486-2346
>  Jan Richards <jan.richards@utoronto.ca>
>
>
>                Jan Richards <jan.richards@utoronto.ca>
>                Sent by: w3c-wai-ua-request@w3.org
>                07/12/2007 03:44 PM
>
>
>              To
>              WAU-ua <w3c-wai-ua@w3.org>
>
>
>              cc
>
>
>
>              Subject
>              Re: User Agent Teleconference for July 12 2007
>
>
>
>
>  Notes from the call:
>
>  http://www.w3.org/2007/07/12-ua-minutes.html
>
>
>  Action items:
>
>  ACTION: JR to Expand on idea of blocking functional areas: animation,
>  low contrast, etc.
>
>  ACTION: PP to Proposal to combine 3.2 and 3.3
>
>  ACTION: JR to Proposal to limit "background image" to body of document
>
>  ACTION: JA to Get thoughts together about 3.4 "All executable content",
>  managing configuration
>
>  ACTION: JR to Proposal to have config uration not to have stripped down
>  user agent windoews
>
>  ACTION: PP to Proposal on ways User Agents could use live regions.
>
>  ACTION: JA to Proposal that if a live region has focus, it shouldn't
>  update.]
>
>
>  Cheers,
>  Jan
>
>
>  Jim Allan wrote:
>  > W3C User Agent Teleconference for July 12 2007
>  > -------------------------------------------------------------
>  > Chair: Jim Allan
>  > Date: Thursday, July 122007
>  > Time: 2:00-3:00 pm Boston Local Time, USA (19:00-20:00 UTC/GMT)
>  > Call-in: Zakim bridge at: +1-617-761-6200, code 8294#
>  > for UK use 44-117.270-6152
>  > IRC: sever: irc.w3.org, port: 6665, channel: #ua.
>  > -------------------------------------------------------------
>  >
>  > Regrets, agenda requests, or comments to the list
>  >
>  > Agenda:
>  >
>  > 1. Changing Meeting time (move meeting time ahead 1 hour)
>  >
>  > 2. Ideas for topics for Tech Plenary day
>  >
>  > 3. Wiki - review edits
>  >    http://www.w3.org/WAI/UA/wiki/UaagDocument
>  >
>  > Jim Allan, Webmaster & Statewide Technical Support Specialist
>  > Texas School for the Blind and Visually Impaired
>  > 1100 W. 45th St., Austin, Texas 78756
>  > voice 512.206.9315    fax: 512.206.9264  http://www.tsbvi.edu/
>  > "We shape our tools and thereafter our tools shape us." McLuhan, 1964
>  >
>
>  --
>  Jan Richards, M.Sc.
>  User Interface Design Specialist
>  Adaptive Technology Resource Centre (ATRC)
>  Faculty of Information Studies
>  University of Toronto
>
>    Email: jan.richards@utoronto.ca
>    Web:   http://jan.atrc.utoronto.ca
>    Phone: 416-946-7060
>    Fax:   416-971-2896
>
>
>
>
>
>
>
>  
>
Received on Friday, 27 July 2007 02:30:29 GMT

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