[Action] Toggling placeholders

Hello,

Per my action item of the 15 March 2001 teleconference [1],
please consider this proposal related to toggling placeholders.
In the 9 March draft [2], checkpoints 3.2 (P1) and 3.7 (P2) involve
configuration requirements to render placeholders instead of
visual content, and to allow activation of these placeholders 
(to view the original content).

(Refer to my related proposal [3] which allows not just rendering
original content in context, but also in a separate viewport.)

Denis stated at the 15 March meeting that some users with
cognitive disabilities might be disoriented by an excess of
visual information, whether that information was rendered 
automatically all at once or as the result of one-at-a-time 
activation of too many placeholders. For this reason, 
he argued that checkpoints 3.2 and 3.7 should also include 
a requirement to toggle video/images back off.

It's possible to achieve the desired results (i.e., rendering
one image at any given moment) by following these steps, 
all guaranteed by existing checkpoints:

 a) Configure the user agent not to render images (3.7)
 b) Replace one placeholder with the associated image (3.7)
 c) Reload the page (giving all placeholders again)
 d) Start at (b) with the next placeholder in the document.

That's not convenient (since you have to reload the page), but
it's possible. Therefore, I propose the following P2 checkpoint:

 3.x If activation of a placeholder required by checkpoints 
 3.2 and 3.7 causes the placeholder to be replaced in context 
 by the original author-supplied content, allow the user to 
 undo the action (by turning the visual content off and the
 placeholder on again).
      Note: If the user agent satisfies the placeholder 
      activation requirement by rendering the author-supplied 
      content in a new viewport, the user can close the new
      viewport per checkpoint 5.3

Comment:

 1) I'm not terribly in favor of adding this checkpoint, but 
    Denis' point is well-taken. I'd be more comfortable if
    this were a P3 checkpoint, but I don't know how serious
    the usability issue is.

 2) Do we have any implementation experience for this? Aaron
    suggested that Mozilla lets users toggle content on and off.

 - Ian
 
[1] http://lists.w3.org/Archives/Public/w3c-wai-ua/2001JanMar/0427
[2] http://www.w3.org/WAI/UA/WD-UAAG10-20010309/
[3] http://lists.w3.org/Archives/Public/w3c-wai-ua/2001JanMar/0454
-- 
Ian Jacobs (jacobs@w3.org)   http://www.w3.org/People/Jacobs
Tel:                         +1 831 457-2842
Cell:                        +1 917 450-8783

Received on Saturday, 17 March 2001 19:13:23 UTC