Summary of and outlook to the style discussion

[Michael Brauer <michael.brauer@sun.com>]

Dear TC members,

following is a summary of discussions and decisions we had so far 
regarding styles:

- the "style:styles", "style:automatic-styles" and "style:master-styles" 
elements were part of the work package 1.2 "first level elements" 
already. It has been discussed whether the "style:automatic-styles" 
element should be renamed, but agreed to not rename it.

- When discussung extensibility at the F2F meeting, we also discussed 
many processing rules for styles. The following is an except from the 
minutes:

--- start ---
C) Attributes for paragraphs/character runs
-------------------------------------------
The TC agreed that styles are suitable and sufficient to further markup
paragraphs and character runs (but also other object types like drawing
objects), provided that
- attributes and elements that are contained in a style but are not
specified in the Open Office XML schema are preserved, and
- multiple styles can be assigned to a paragraph, character run, etc.
Since current office suite implementations support only single styles,
and since supporting multiple styles seems not to be easy to implement,
the TC unanimously agreed to the following:
- A "class" attribute will be added to all elements that reference a
style already. The value of this class attribute is of XML type IDREF (
http://www.w3.org/TR/REC-xml#idref) and contains a
list of styles that are applied to the object additionally to the style
referenced by the "style-name" attribute. Formatting attributes
contained in styles referenced by the "class" attribute are evaluated in
the order the style names appear in the list. The style referenced by
the "style-name" attribute is treated like being the first style in the
list. Conforming application _should_ support this new attribute and
also _should_ preserve it while editing.
- Attributes and elements that are contained in the "properties" element
of a style but are not specified by the Open Office XML schema _should_
be preserved by conforming applications.
- To be usable in a list, styles referenced by a "class" attribute must
not contain space characters. For this reason, a "display-name" has to
be added to styles. A description is also considered to be useful by the
TC. The schema details of classes will be discussed by e-mail on the
TC's mailing list.

D) Character runs across paragraph boundaries
---------------------------------------------
The TC unanimously agreed that the extensions mechanism defined in C)
can be used to support character runs across paragraph boundaries. Such
runs can be split at the paragraph boundaries, and an (user defined)
"id" attribute can be added to the style referenced by the two new runs
to specify that both runs actually are a single one.

E) Forward compatibility
------------------------
As stated above, the TC unanimously agreed that conforming applications
should preserve all attributes and elements contained in the
"properties" element of styles and are not specified in the Open Office
XML schema.
--- end ---

During the face-to-face meeting, we also had the proposal to replace the 
<style:properties> element, that can take any kind of formatting 
properties (text, paragarph, graphic, etc.), with a set of more specific 
ones (like <style:text-properties>, <style:paragraph-properties>, etc.) 
that can only take formating properties of a certain kind. Additionally 
it has been proposed to use <style:style> element also for special 
styles (like <style:list-style> or <style:outline-style>) by extending 
the value set of the "style:family" attribute.

I suggest that we start our discussions by having a look at the 
<style:style> element and its usage and with the above proposals 
(covering the work packages 5.1 (Style Structure) and 5.2 (Style Basics) 
as described in 
http://lists.oasis-open.org/archives/office/200301/msg00027.html), and 
that we continue the discussion with the various text formatting 
properties. They can be found in section 3.10 of the OpenOffice.org 
specification that starts on page 203.

Best regards

Michael