Sometimes new features take several releases before they are finally done. That happened and still happens for the custom property text fields in Writer.

In the old StarOffice times a documents could have four “user defined” properties that were stored in the “document summary information” stream of the OLE Storage based file format, along with other meta data like title, subject etc. Each of these properties could have a name and a (string) value. We still have these properties in the current OOo version. We also have text fields in Writer that refer to these properties in the same way as other document info fields refer to the built-in properties “Subject”, “Title” etc. These fields can be found in the “DocInformation” tab of the “Insert Fields - Other” dialog.

ODF is a big improvement over that: it allows for an arbitrary number of user defined properties that also can have other types than string (number and date). Again they are stored together with the built-in properties, now in the meta.xml stream of ODF document.

Until now we didn't provide any Writer text fields to support the user defined properties in OOo, though ODF also knows them. It was just one of all the things we still have to do. And we also didn't support these properties in the “Document Properties” dialog, we still have the notorious four properties with string values there. In the current OOo version adding, removing and changing user defined properties can be done only by manual editing of the meta.xml or by using a UNO API at runtime.

Using this API in Basic is quite simple:

if not ThisComponent.DocumentInfo.PropertySetInfo.HasPropertyByName("MyProp") then
    ThisComponent.DocumentInfo.AddProperty("MyProp",0,"")
endif
ThisComponent.DocumentInfo.MyProp = "MyValue"
print ThisComponent.DocumentInfo.MyProp

adds a user defined property called “ MyProp” and assigns the value “MyValue” to it and then displays the value of the property in a message box.

ThisComponent.DocumentInfo.RemoveProperty("MyProp")

will remove the property again.

In OOo2.0 we added the import of Word, Excel and Powerpoint custom properties and document variables into ODF user defined properties by using this API internally in our import filter. This enabled users to port their solutions (mostly VBA macros) using the properties in Word documents into OOo Basic, Java, Python or whatever language they used for automating OOo.

In OOo2.4 we now add Writer text fields that directly support these properties. If a document has user defined properties, the “Insert Fields - Other” dialog will show them in the tab “DocInformation” so that users can create fields based on them. Though the ODF specification uses the term “ user defined” for both the properties and the text fields we think that users are more accustomed to “custom” properties and fields and so we decided to use that in our user interface. Another reason was that we don't want to confuse the “user defined fields” with the “user fields” we already have.

These new text fields will of course also be used for importing Word custom fields. Until now they had been imported as “user fields” that just show a snapshot of the property value but don't get updated when this value is changed (e.g. by the API shown above).

What we are now missing is a UI that allows to add, remove and change custom properties like it is possible for our current four string properties. This new UI will be provided in OOo3.0 and it will replace the “user defined” tab page in the “document properties” dialog.

Feedback is welcome – either on the dev[at]sw.openoffice.org mailing list if your comment is more development related or on discuss[at]ux.openoffice.org if you want to discuss the user interface.