renewed proposal for new position and space attributes for the listlevel

[Oliver-Rainer Wittmann - Software engineer - Sun Microsystems Inc<Oliver-Rainer.Wittmann@Sun.COM>]

Dear TC members,

I want to renew my proposal for new attributes for the list-level 
style in order to provide a clear view for the voting process. The new 
attributes provide an new possibility to specify the position und 
spacing of the list label and the list item itself:

The new attributes for the list level style are:
- text:label-followed-by
- text:list-tab-stop-position
- text:label-aligned-at
- fo:margin-left
These new attributes plus the existing attribute fo:text-align give 
the possibility to specify the position and spacing of the list label 
and the list item in a new way, which could be called position and 
spacing via label alignment.
The existing attributes text:space-before, text:min-label-width and
text:min-label-distance plus fo:text-align defines somehow the 
position and spacing via label size and position.

The new attributes are grouped together in a new element, named
style:list-level-label-alignment. This element has to contain the
attribute text:label-followed-by. Attributes 
text:list-tab-stop-position, text:label-aligned-at and fo:margin-left
are optional. if any of these attributes are missing, its values is
assumed to be 0.

In order to decide, which group of attributes are used to define the
position and spacing of the list label and the list item the new
attribute text:list-level-position-and-space-mode is introduced.

- text:list-level-position-and-space-mode:
<define name="style-list-level-properties-attlist" combine="interleave">
    <optional>
       <attribute name="text:list-level-position-and-space-mode">
	 <choice>
	    <value>label-width-and-position</value>
	    <value>label-alignment</value>
	 </choice>
       </attribute>
    </optional>
</define>

Meaning of these values:
- label-width-and-position:
The existing attributes text:space-before, text:minimum-label-width,
text:minimum-label-distance and fo:text-align are used to define the
position and spacing of the list label and the list item.

- label-alignment:
The new attributes and fo:text-align are used to define the position and
spacing of the list label and the list item. The values of the existing
attributes for text:space-before, text:minimum-label-width and
text:minimum-label-distance are treated as 0.

If attribute text:list-level-position-and-space-mode is missing, which
is hold for documents conforming previous ODF versions, its value is
assumed to be label-width-and-position.


- text:label-followed-by:
<define name="style-list-level-label-alignment-attlist"
combine="interleave">
    <attribute name="text:label-followed-by">
       <choice>
	 <value>listtab</value>
	 <value>space</value>
	 <value>nothing</value>
       </choice>
    </attribute>
</define>

Meaning of the values of attribute text:label-followed-by:
- listtab - a tab stop follows the list label before the text starts.
- space - a space character is inserted after the list label before
the text starts.
- nothing - the text starts directly after the list label.


- text:list-tab-stop-position:
<define name="style-list-level-label-alignment-attlist"
combine="interleave">
    <optional>
       <attribute name="text:list-tab-stop-position">
	 <ref name="nonNegativeLength"/>
       </attribute>
    </optional>
</define>

Attribute text:list-tab-stop-position is only relevant, if attribute
text:label-followed-by is defined and its value equals "listtab". In all
other cases, attribute text:list-tab-stop-position isn't evaluated.
Attribute text:list-tab-stop-position specifies an additional tab stop,
which is inserted into the list item. Typically, this tab stop is the
one, which is applied after the list label. Thus, the text of the
first line of list item typically starts at this tab stop. In
left-to-right layout environments this tab stop is interpreted as a
left tab. While in right-to-left layout environments its interpreted
as a right tab.
There exists two cases in which this additional tab stop isn't applied
to start the text of the first line of the list item after the list label:
- The position of the additional tab stop is before the end of the
list label.
- Between the end of the list label and the position of the additional
tab stop exists already a tab stop at the list item.
In these cases an existing respectively a default tab stop is applied
after the list label. The additional tab stop can be applied by normal
inserted tab characters in the list item in these cases.
The additional tab stop can also been applied in the text lines, which
follow the first line of the list item.


- text:label-aligned-at
<define name="style-list-level-label-alignment-attlist"
combine="interleave">
    <optional>
       <attribute name="text:label-align-at">
	 <ref name="Length"/>
       </attribute>
    </optional>
</define>

The new attribute text:label-aligned-at specifies the alignment position
for the list label. The list label is aligned at this position, because
value of text:minimum-label-width is treated as 0:
- fo:text-align = "left": The list label starts at the alignment position.
- fo:text-align = "center": The center of the list label is positioned
at the alignment position.
- fo:text-align = "right": The list label ends at the alignment position.


- fo:margin-left
<define name="style-list-level-label-alignment-attlist"
combine="interleave">
    <optional>
       <attribute name="fo:margin-left">
	 <ref name="Length"/>
       </attribute>
    </optional>
</define>

The new attribute fo:margin-left is only relevant, if attribute
text:label-followed-by is defined. It specifies the indent of the text
lines of the list item following the first line.


The new attributes text:label-aligned-at and fo:margin-left for a list
level style are competing with the paragraph indent attributes
fo:text-indent and fo:margin-left. The same is hold for the
corresponding paragraph indent attributes for a paragraph style.
These paragraph indent attributes are used to calculate the indent of
first line of the paragraph and the indent of the following lines:
- first line indent = fo:text-indent + fo:margin-left
- following lines indent = fo:margin-left

In the following is described how this competition is solved.

- List style with list level style directly applied to a paragraph via
an automatic paragraph style:
If neither paragraph indent attribute fo:text-indent nor paragraph
indent attribute fo:margin-left are defined, the new list level style
attributes text:label-aligned-at and fo:margin-left are used in order
to determine the indentation of the paragraph.
If one of the paragraph indent attributes are defined - the value of
the missing one is assumed to be 0 -, the given values of list level
style attributes text:label-aligned-at and fo:margin-left are ignored.
For the alignment position for the list label the first line indent is
used. For the indent of the following lines of the list item the
paragraph following line indent is used.

- List style with list level style applied to a paragraph via an
attribute of a paragraph style:
The new attributes label-aligned-at and indent-at of a certain list
level of a list style are used as indent attributes for a paragraph,
which have such a paragraph style applied, if neither the automatic
paragraph style nor the paragraph style provides own indent attributes 
(fo:text-indent and fo:margin-left). If indent attributes are given at
the automatic paragraph style or the paragraph style, these attributes
are used to determine the alignment position and the indent for the 
text lines following the first line.


The new attributes inclusive its explanations should be inserted into 
chapter 15.12 "List-Level Style Properties", referencing to ODF 1.1 
specification document.


The new attributes cover the following use cases. These use cases are 
hard or even impossible to be expressed with the existing attributes:
(1) Imagine the following list item layout:
- center align the list label of the list items at absolute position 
2cm - center of the actual list label is at absolute position 2cm
- start of the text of the first line and the following lines at 
absolute position 3cm.
This list item layout can be expressed using the new attributes:
text:label-followed-by="listtab"
text:list-tab-stop-position="3cm"
text:label-aligned-at="2cm"
text:indent-at="3cm"
fo:text-align="center"

(2) List item layout
- start the list label at absolute position 2cm
- start of the text of the first line at absolute position 3cm
- start of the text of the following lines at absolute position 4cm.
can be expressed by the new attributes:
text:label-followed-by="listtab"
text:list-tab-stop-position="3cm"
text:label-aligned-at="2cm"
text:indent-at="4cm"
fo:text-align="left"

(3) Think of the following list item layout:
- right align the list label at absolute position 2cm - list label end 
at absolute position 2cm
- start of the text of the first line directly after the list label 
separated by a space
- start of the following lines at absolute position 5cm.
This is easy to be expressed with the new attributes:
text:label-followed-by="space"
text:list-tab-stop-position="5cm"
text:label-aligned-at="2cm"
text:indent-at="5cm"
fo:text-align="right"


Please support my proposal and vote on it, even when I'm not attending 
the TC call, because I'm sick or on vacation.


Regards, Oliver.