Loretta's analysis of UAAG Guideline 9

UAAG Guideline 9 (Provide Navigation Mechanisms), provides access to 
content through a variety of navigation mechanisms, including sequential 
navigation, direct navigation, searches,and structured navigation. These 
issues seem like they should be covered by WCAG 2.4 (Provide mechanisms to 
help users find content, orient themselves within it,and navigate through 
it), possibly in conjunction with WCAG 2.1 (Make all functionality operable 
via a keyboard or keyboard interface) and and WCAG 3.2 (Organize content 
consistently from "page to page" and make interactive components behave in 
predictable ways).

I reviewed the checkpoints of UAAG 9  to see whether all the issues are 
addressed. The P1 checkpoints for UAAG 9 are:


9.1 Provide content focus

     * Provide at least one content focus for each viewport (including 
frames) where enabled elements are part of the rendered content.
     * Allow the user to make the content focus of each viewport the 
current focus.

9.1 seems to be covered by WCAG 2.1.



9.2 Provide user interface focus

     * Provide a user interface focus.

9.2 seems to be a user agent responsibility



9.3 Move content focus

     * Allow the user to move the content focus to any enabled element in 
the viewport.
     This seems to be covered by WCAG 2.1, but it may be possible to invoke 
functionality via the keyboard without actually moving focus to an enabled 
element, for instance, by providing keyboard shortcuts. At level 2, WCAG 
3.2 requires that all user interface components should be able to receive 
focus without causing activation.

     Allow configuration so that the content focus of a viewport only 
changes on explicit user request.

     Nothing in WCAG seems to cover this requirement. It requires, for 
instance, that it be possible to configure the user agent so that scripts 
can't move the focus as a side effect of something else. If we consider a 
change in focus to be an extreme change of context, if might be covered by 
GL 3.2, but I think this is not what was intended by extreme change of context.
     * If the author has not specified a navigation order, allow at least 
forward sequential navigation, in document order, to each element in the 
set established by provision one of this checkpoint.
     This seems to be covered by WCAG 2.4, by the requirements at level 3 
related to sequences. We might need to  promote them to level 1 to cover 
this requirement.

9.4 Restore viewport state history

     * For user agents that implement a viewport history mechanism, for 
each state in a viewport's browsing history, maintain information about the 
point of regard, content focus, and selection.
     * When the user returns to any state in the viewport history (e.g., 
via the "back button"), restore the saved values for the point of regard, 
content focus, and selection.

9.4 seems to be a user agent responsibility.


Recommendation:

1. Add the following success criterion to GL 3.2, level 1:

Any change of content focus is implemented in a way that can be 
programmatically identified.

2. Promote the following success criteria of GL 2.4 to level 1:
     * When content is arranged in a sequence that affects its meaning, 
that sequence can be determined programmatically.
     * When a page or other delivery unit is navigated sequentially, 
elements receive focus in an order that follows relationships and sequences 
in the content

Received on Tuesday, 19 April 2005 22:53:09 UTC