20120416
========

Experimenting
-------------

I launch LibreOffice, create an empty text document and save it as "a.odt".
Then I add three Custom Properties...

.. image:: 0416/0416a.jpg
  :scale: 90


... then save the file under a name `b.odt`.

Then I compare the content of the .odt package. 
The only difference is in `meta.xml`::

  <office:document-meta xmlns:office="urn:oasis:names:tc:opendocument:xmlns:office:1.0" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:meta="urn:oasis:names:tc:opendocument:xmlns:meta:1.0" xmlns:ooo="http://openoffice.org/2004/office" xmlns:grddl="http://www.w3.org/2003/g/data-view#" office:version="1.2">
  <office:meta>
  ...
  <meta:user-defined meta:name="Date" meta:value-type="date">2012-04-16</meta:user-defined>
  <meta:user-defined meta:name="bool" meta:value-type="boolean">true</meta:user-defined>
  <meta:user-defined meta:name="name">name</meta:user-defined>
  </office:meta>
  </office:document-meta>

Great! So it should be easy to add values for these variables when generating an .odt.

But oops: 
Custom Document properties are not accessible when specifying 
`conditions <http://help.libreoffice.org/Writer/Defining_Conditions>`_! 
(At least I didn't get it to work and I didn't find 
any documentation that states is would.)

Same exercise with a document where I inserted custom fields using "Set Variable" and "Show Variable". Now the difference is in the `content.xml`, inside the `<office:text>` element. Before the first `<text:p>` there is now a new `<text:variable-decls>` container, a global list which LO obviously has  automatically guessed::

  <text:variable-decls>
  <text:variable-decl office:value-type="string" text:name="last_name"/>
  <text:variable-decl office:value-type="date" text:name="date_issued"/>
  </text:variable-decls>
  
After this, here is how "Set Variable" fields look like::

  <text:p text:style-name="Standard">Set Variable last_name = <text:variable-set text:name="last_name" office:value-type="string">Arens</text:variable-set> , date_issued = <text:s/>
  <text:variable-set text:name="date_issued" text:formula="ooow:40981" office:value-type="date" office:date-value="2012-03-13" style:data-style-name="N38">Dienstag, 13. März 2012</text:variable-set> </text:p>
  </text:p>

And "Show Variable" fields look similar::

  <text:p text:style-name="Standard">Show Variable last_name = <text:variable-get text:name="last_name" office:value-type="string">Arens</text:variable-get>, date_issued = <text:s/>
  <text:variable-get text:name="date_issued" office:value-type="date" style:data-style-name="N36">13.03.2012</text:variable-get>
  </text:p>

It should be easy, using :term:`ODFPy`, to generate a document with 
predefined variables:

- ``<text:variable-decls>`` --> `text.VariableDecls`
- ``<text:variable-get>`` --> `text.VariableGet`
- ``<text:variable-set>`` --> `text.VariableSet`