Re: Saving objects in goffice

[Jean Bréfort <jean brefort ac-dijon fr>]

Jody Goldberg wrote:

> On Sat, Feb 21, 2004 at 11:44:19AM +0100, Jean Brefort wrote:
>  
>
> > Hi,
> >
> > I am writing the code to add error bars in graphs. I am ipmlementing
> > error bars as properties in GogSeries. My concern is that I don't think
> > necessary to have anything about error bars saved when the default (no
> > bars) applies. With the current implementation (use of the GogPersistDOM
> > interface), we'll have always something saved. This is also true for
> > GogStyle even when the default is used.
> >
> > A simple solution to this is to change the GogPersistDOM interface so t
> > that the save method returns a boolean value:
> >
> > <    void     (*save) (GogPersistDOM *gpd, xmlNode *parent);
> >    
> >
> > >         gboolean     (*save) (GogPersistDOM *gpd, xmlNode *parent);
> > >      
> > and in gog_object_write_property:
> >
> >         case G_TYPE_OBJECT:
> >                 val_obj = g_value_get_object (&value);
> >                 if (val_obj != NULL) {
> >                         if (IS_GOG_PERSIST_DOM (val_obj)) {
> > <                            gog_persist_dom_save (GOG_PERSIST_DOM (val_obj), node);
> >    
> >
> > >                                 success = gog_persist_dom_save (GOG_PERSIST_DOM (val_obj), node);
> > >      
> >                         } else
> >
> > Also, success should be FALSE if val_obj is NULL.
> >    
>
> Hmm, that does not fit well with my plans to ditch the DOM interface
> and move to SAX alone.  For that we won't have the luxery of knowing
> not to export the wrapper if the object's export fails. 
>  
>
>
> Why is the val_obj != NULL test insufficient ?
>  
The node will be saved even if empty since by default success is TRUE.