Presentation Notes

Daniel Dardailler - Accessibility and XML

W3C Workshop on Web Device Independent Authoring
Wednesday 4 October 2000

Notes taken by Gregory Rosmaita

XML is one level up from specific languages; can
create own elements; issues: equivalencies, unknown
semantics; need for schemas and DTDs

W3C draft note on XML from PF WG trying to provide
guidance for creators of XML languages; definitions,
guidelines and examples; similar to what done several
years ago with SGML

idea is something is accessible if can be understood
regardless of device used to access it

4 Guidelines
1. when create language, allow authors to associate
textual description with non-textual elements of
language; graceful degradation

2. consider the right level of semantics; separate
content from presentation; should contain all of the
content and structure that can be interpreted in device
independent manner (classification, grouping,
navigation, equivalencies)

3. export semantics when create new language; can
do with human readable documentation; can use
DTDs, schemas that describe semantics and not just
syntax; reuse modules and languages with well
known languages (XLINK for links); will make user
capable of using your language because will be
interpreted in a way the user expects it to work; create
own elements and provide mapping to XML/XHTML

4. accessible user interface -- specific to styling of
language; default stylesheet for all different media

conclusion: think DI when create new language and
export semantics; all languages we create today at
W3C have conformance section that requires
accessibility for different usages of spec (UA,
Authoring Tool)

1. export semantics -- how do you find semantics on
client side; have to have a way to go back to a
document that provides schema or human
documentation; still open question (packaging activity
--package all meta-level information of a language)

Q: use of the word "allow" and "advise" should be
understood will become "require" and "demand"
before we're through with all of this;
CMN: that's the conformance piece; in order for
content to conform, must meet certain requirements;
make sure it is there or you don't conform
Q: with XML where browsers aren't forgiving; ALT
required in HTML, but can get away with it; need
something in XML to put things in as requirements, as
opposed to "allow"
A: issue is that there are some cases where it is
counter intuitive to require descriptions to be attached
in a certain way; want to provide several methods of
providing equivalency
DP: well-formed rather than valid documents being
used; number of documents that are well formed
rather than valid allow people to abuse XML
Q: enabling and improving accessibility -- export
semantics of list; depending on framework of design,
hard to hard code requirements; may be ways of
exporting semantics that haven't been thought of yet;
impossible to have requirements without being
specific; textual equivalents should be required, yes,
but others not easy, due to vagueness
Q: mobile requirements? data sets (non-UI reliant)?
A: there are 2 types of XML - machine-centric and
user centric; accessibility note only about user centric;
machine centric accessible because had to be
understood by machine