User Agent Comments on XHTML 2.0 31 January Public Working Draft
This document was prepared by the UAWG for discussion with the HTML WG
at a 7 March meeting in Boston. These comments are based on the
XHTML™ 2.0 W3C
Working Draft 31 January 2003.
This document has been superseded by the
May 2003 draft.
Editor: Jon Gunderson
Last modified: $Date: 2003/06/06 11:56:37 $
General Comments
- XHTML 2.0 includes user agent behavior requirements. IJ to talk
separately about general issue of conformance for user agents.
- UAWG would like to discuss:
- Which UAAG 1.0 requirements apply to exisiting xhtml 2.0
behaviors (see IJ review for details)
- What new behaviors we would like xhtml 2.0 user agents to
display
- What is the expectation that XHTML 2.0 can include new
functionalities?
See also additional comments from
Ian, and comments from Matt.
Navigation
- User scenarios:
-
- User wants to move viewport to important parts of content on current
page.
- User wants to find important content and dig down from there.
- User wants to skip or navigate to collections of links (navigation
bars)
- User wants to know whether the links are internal, external or
recently visited
- User wants to move back and forth between content on this page and
links to other pages
- content navigation
-
- navigation within a given page, to and around important content,
to and around navigation bars.
- Allow author to identify important parts of content. User agent
allows user to move viewport to those parts of content, or to hide types of
content (e.g., MAP, nl)
- Limits of tabindex: serial only, scoping issues.
- How to convey author-supplied keyboard shortcuts to user
- How to allow user to override author-specified bindings to meet
their needs.
- definition of focus
-
- Clear distinction between focus and selection
- Focus does not apply to pointer in UAAG 1.0.
- Hand-off to plugins
- navigation lists
-
- User should be able to move focus to first active element after
the navigation (section 508 requirement)
- User should be able to sequentially move focus to first link in
each navigation list in a resource
- Need to be able to have a static view of all links
- Need at least configuration so that link text is legible above
background content.
- UAAG 1.0 requires that everything be keyboard operable.
- Navigation lists should have a user-specifiable static rendering to accommodate people with
motor disabilities.
- Is it decided how nl will control XFrames?
Access to content
- Make it easy for author to (without redundancy) to provide semantics
that benefit user agents:
- Association of alternative content. This becomes more difficult
when every element has an src attribute. The object element helps since
alternatives are embedded; this may be lost if everything can pull in external
multimedia content.
- Identification of conditional content. Use of SMIL/switch would
facilitate this (with user agent behavior to provide access to unrendered
alternatives).
- May not be a good idea for all elements to be links. Users rely on
link text to understand the target of the link. It may not be helpful to users
to make an entire paragraph a link.
- Challenges of nested links
- Nested anchors seems fine.
- Rendering of nested links may be difficult for users to perceive,
notably when rendered as audio.
- May complicate user interface; user may not realize what part of
content embodied which link. This is already the case today with visually
rendered links that are adjacent and not distinguishable as two adjacent links;
usability issues.
- Multiple links not impossible to manage (e.g., could be managed
through menus), but what are the benefits to users?
- Elements that declare src should at all times have alt content. There may be
a case to create an attribute that indicates the object has no semantic value, to replace the
current use of alt="". We can then require alt content to be valid, as we do now,
by saying that items with src either need a text node inside, or declare the content
means nothing. That is, <object src="banner.png"/> is probably not accessible,
so should be invalid. A similar case is noted under "Tables" below.
- How can author convey important semantic areas of pages for pages
that are not based on nested headings?
Design issues
- Often several ways to accomplish the same goal; is that desirable or
will it lead to confusion? Example of MAP content with AREA or not. Get rid of
AREA element?
- Delete block/inline distinction; what elements can be deleted as a
result? For interoperability, define default rendering in terms of CSS
properties.
Presentation and style
- Need to be able to apply style sheets to alternative content.
- Need to allow user to choose from among alternative style sheets,
turn off author and user style sheets.
- User wants to hide types of content in order to improve
readability.
- Simplified views of content
- outline view based on headers
- configuration of important content
Tables
- Alternative renderings on configuration?
- Are attributes/elements from HTML 4 really used/useful?
- Layout tables may continue to exist, despite best efforts. May need a way to declare
that a table is for visual layout only.
Specific Comments
- Example should also include when images are configured not to be
rendered
- Forward and Reverse Links
- Users should be notified of the availability of forward and reverse
links
- Users should be able to activate forward and reverse links
- Style Sheets
- User should be able to select from available style sheets for the
media types supported by the device
- Be able remember user preferences bewteen style sheets
- User preferences for nested objects
- A mechanism for API to pass user text styling information to an
OBJECT (no consensus on this one)
- User should be able to configure not to render some types of OBJECT
content supported by the device
- User Selection of alternatives
- User should be notified of other conditional content to be
present
- User be able to query the OBJECT for alternatives and be able to
select from the alternatives supported by the device