[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]
Subject: Re: [office] Proposal: To add default value fordraw:auto-grow-height,draw:auto-grow-width,fo:wrap-option,style:flow-with-text
Hi, it is even more difficult. Within styles, formatting properties that are not set in a specific style are inherited from the parent style. I'm not sure under which circumstances an a:defaultValue attribute is evaluated by a parser. But if a default value is specified by an a:defaultValue attribute within a style, and if it is evaluated, then this entirely breaks the inheritance feature, because every style then defines all formatting properties and assigns the default values to them. Formatting properties defined in parent styles won't be evaluated any longer. That's actually the reason why for no formatting property, an a:defaultValue attribute is specified. Another difficulty for specifying default values on the schema level is that formatting properties are re-used for different kind of objects and style families, and that their default they may differ for the different document types. The default margin of a paragraph style (that it is applied to a paragraph) may for instance be different than that of a graphic style (that is applied to the geometry of the drawing shape), and the default font size may differ between text and spreadsheet document. A basic feature of ODFs style inheritance model are default styles (section 15.2). They allows to specify default values for each style family, that then apply to the full document. So, if one wants to make sure that a certain formatting property has a certain default value, then this is possible already by specifying it in the default style. However, for formating properties for which no default is specified in the default styles and styles of a document, a user or application defined value is used. This on the one hand allows to leave it open by intention which value is used, what may be actually reasonable for properties that are often user defined or system depended (for instance font names and sizes, or for the paper size). But on the other hand this means that applications may use different defaults. If we want to provide more guidance what typical user settings or application defaults are, I could image that we provide (informative) sample or (normative) reference default stylesheets in the form of ODF fragments (or separate ODF documents?), or that we add (informative or normative) tables which list the default values for those properties, for which reasonable defaults can be specified. I think we should have a deeper look into this on the next con call. Best regards Michael Bruce D'Arcus wrote: > Zhi Yu Yue wrote: > >> The following proposal aims to add default value for several >> attributes in the graphic properties, respectively "fo:wrap-option", >> "draw:auto-grow-height", and "draw:auto-grow-width". Currently, there >> is no default value defined for these attributes. It will cause >> ambiguity when there is no such property specified in the >> graphic-properties. > > I'd be careful about relying on default values. RELAX NG does not -- by > design -- include formal support for default values. To quote James > Clark [1]: > > "9. Another problematic area in W3C XML Schema is the support for > infoset augmentation, such a default attributes. Experience with XML > 1.0 has, I believe, shown that this is not a good feature to include > in a schema language. Apart from being a violation of modularity, it > tends to cause interoperability problems, because it leads to the > possibility of the application getting different information depending > on whether or not validation has been performed. RELAX NG, by > contrast, never changes the information that an application receives. > It specifies purely what is valid and what is invalid." > > Maybe it's not an issue here, but just wanted to point it out. > > Bruce > > [1] <http://www.imc.org/ietf-xml-use/mail-archive/msg00217.html> -- Michael Brauer, Technical Architect Software Engineering StarOffice/OpenOffice.org Sun Microsystems GmbH Nagelsweg 55 D-20097 Hamburg, Germany michael.brauer@sun.com http://sun.com/staroffice +49 40 23646 500 http://blogs.sun.com/GullFOSS Sitz der Gesellschaft: Sun Microsystems GmbH, Sonnenallee 1, D-85551 Kirchheim-Heimstetten Amtsgericht Muenchen: HRB 161028 Geschaeftsfuehrer: Wolfgang Engels, Dr. Roland Boemer Vorsitzender des Aufsichtsrates: Martin Haering
[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]