(PFWG) ACTION-211 Query re: SVG Request for @order for Access Module

aloha!

today at the XHTML2 weekly teleconference, i took advantage of the 
presence of doug schepers (staff contact for, amongst others) the 
SVG working group...  i posed the basic question that PF tasked me 
with taking back to the SVG and XHTML2 working groups, namely:

"Does mixing roles and ids with targetrole and targetid for @order ok 
or does it pose problems, and if so what problems?"

the results of the conversation this morning are:

1. mixing roles and ids with targetrole and targetid for @order should
not pose a problem -- typically, the @order list will contain one or the 
other -- and, according to the current wording of the editor's draft 
being drafted, requires that one OR the other be used; if the @order 
list has both, then the listed targetroles will be ignored.

2. scenario: a document instance with 3 roles: A, B, and C, defined by 
the author as:

order="a b c"

what is the expected result?

expected result: the user would go through all A roles, then all B roles, 
and then all c roles

3. point 2, above, raises the question: "where does one start?" From 
the current focus (however it is established when the document instance 
is loaded, or should defining an order mean that traversal begins with 
the first item-type listed in the order attribute

as doug explained, the starting point is predicated on user selection, 
if @order is not defined, then the UA should locate the next document 
order id; if order is defined, then commencing navigation starts with 
the top of the list, unless the item upon which the user established 
focus is in the @order list; if the item with current focus is not in 
the list, then the UA would go to first item on list; if the item is 
included in the @order list, then the UA would move focus to the next 
item listed

shane mccarron pointed out that it is possible to make the starting 
point "stateless" by defining in the spec that "if no item that would 
be selected has current focus, start with the first item in document 
order, otherwise find the next item in the author-defined navigation 
order and start the traversal cycle from that point.

the question of where does one start when @order has been defined is 
an issue we should examine closely, as there are those who argue that
it is impossible to use a document instance when an assistive 
technology is running and there is no pre-determined/pre-defined item
on which to set the initial focus; is a "stateless" starting point --
which might open the door to greater user control over the @order 
list -- how might this be achieved?

finally, the question then arose "what happens when there is a DOM 
mutation that changes the number of roles (adding or subtracting from 
them)?"; if that happens, then the User Agent should/must find the 
next item, even if that item is a new item added by a DOM mutation
event...

so, it is now up to PF to consider the ramifications of the answers
to our question in regards the order attribute for the Access Module

gregory.
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It is better to ask some of the questions than to know 
all the answers.                      -- James Thurber
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Gregory J. Rosmaita, oedipus@hicom.net
         Camera Obscura: http://www.hicom.net/~oedipus
Oedipus' Online Complex: http://my.opera.com/oedipus
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Received on Wednesday, 6 August 2008 15:13:03 UTC