|  |  |  | Libbonobo Reference Manual |  | 
|---|---|---|---|---|
| Top | Description | Object Hierarchy | ||||
| BonoboPersistFileBonoboPersistFile — Interface for anything that can save / load itself from a file. | 
BonoboPersistFile; int (*BonoboPersistFileIOFn) (BonoboPersistFile *pf,const CORBA_char *uri,CORBA_Environment *ev,void *closure); BonoboPersistFileClass; BonoboPersistFile * bonobo_persist_file_new (BonoboPersistFileIOFn load_fn,BonoboPersistFileIOFn save_fn,const gchar *iid,void *closure); BonoboPersistFile * bonobo_persist_file_construct (BonoboPersistFile *pf,BonoboPersistFileIOFn load_fn,BonoboPersistFileIOFn save_fn,const gchar *iid,void *closure);
The PersistFile interface is a useful interface for Bonoboizing legacy applications, however, for new / correct applications it is far preferable to implement the BonoboPersistStream interface, since this will not only result in a nice clean to your application architecture, but also allow the transparent use of local, remote, and synthetic streams.
This interface works by connecting callbacks to the methods, in a pretty deprecated fashion, it is probably better nowadays to simply sub-class the BonoboXObject and override the epv methods. Either way, after all the caveats here is an example use:
Example 25. Persist file implementation
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 | static gint load_from_file (BonoboPersistFile *pf, const CORBA_char *filename, CORBA_Environment *ev, void *closure) { EogImageData *image_data = closure; g_warning ("Load from '%s'", filename); return 0; /* Return 0 on success */ } static gint save_to_file (BonoboPersistFile *pf, const CORBA_char *filename, CORBA_Environment *ev, void *closure) { EogImageData *image_data = closure; g_warning ("Save to '%s'", filename); return 0; /* Return 0 on success */ } | 
Having implemented the callbacks we then have to register them
and aggregate the interface to our object:
  
Example 26. Aggregating a new PersistFile
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 | EogImageData * eog_image_data_construct (EogImageData *image_data) { BonoboObject *retval; BonoboPersistFile *file; file = bonobo_persist_file_new ( load_from_file, save_to_file, image_data); if (file == NULL) { bonobo_object_unref (BONOBO_OBJECT (image_data)); return NULL; } bonobo_object_add_interface (BONOBO_OBJECT (image_data), BONOBO_OBJECT (file)); return image_data; } | 
Note again, that you should be writing a BonoboPersistStream
interface, however if you have already done this you might like
to just have hooks through so that old apps can use the PersistFile
interface:
  
Example 27. Chaining to a PersistStream implementation
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 | static gint load_from_file (BonoboPersistFile *pf, const CORBA_char *filename, CORBA_Environment *ev, void *closure) { Bonobo_PersistStream ps = closure; BonoboStream *stream; stream = bonobo_stream_open ( BONOBO_IO_DRIVER_FS, filename, Bonobo_STORAGE_READ, 0); if (!stream) return 0; .. extract content type from file ... Bonobo_PersistStream_load (ps, type, ev); return 0; /* Return 0 on success */ } static gint save_to_file (BonoboPersistFile *pf, const CORBA_char *filename, CORBA_Environment *ev, void *closure) { Bonobo_PersistStream ps = closure; BonoboStream *stream; stream = bonobo_stream_open ( BONOBO_IO_DRIVER_FS, filename, Bonobo_STORAGE_WRITE | Bonobo_STORAGE_CREATE, S_IRUSR | S_IWUSR | S_IRGRP); if (!stream) return 0; .. work out content type we want to save ... Bonobo_PersistStream_save (ps, type, ev); return 0; /* Return 0 on success */ } | 
  The mime type data can be extracted from gnome-vfs or gnome-mime.
typedef struct _BonoboPersistFile BonoboPersistFile;
BonoboPersistFile is deprecated and should not be used in newly-written code.
int (*BonoboPersistFileIOFn) (BonoboPersistFile *pf,const CORBA_char *uri,CORBA_Environment *ev,void *closure);
BonoboPersistFileIOFn is deprecated and should not be used in newly-written code.
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typedef struct {
	BonoboPersistClass parent_class;
	POA_Bonobo_PersistFile__epv epv;
	/* methods */
	int   (*load)             (BonoboPersistFile *ps,
				   const CORBA_char  *uri,
				   CORBA_Environment *ev);
	int   (*save)             (BonoboPersistFile *ps,
				   const CORBA_char  *uri,
				   CORBA_Environment *ev);
	char *(*get_current_file) (BonoboPersistFile *ps,
				   CORBA_Environment *ev);
} BonoboPersistFileClass;
BonoboPersistFileClass is deprecated and should not be used in newly-written code.
BonoboPersistFile * bonobo_persist_file_new (BonoboPersistFileIOFn load_fn,BonoboPersistFileIOFn save_fn,const gchar *iid,void *closure);
bonobo_persist_file_new is deprecated and should not be used in newly-written code.
Creates a BonoboPersistFile object.  The load_fn and save_fn
parameters might be NULL.  If this is the case, the load and save 
operations are performed by the class load and save methods
| 
 | Loading routine | 
| 
 | Saving routine | 
| 
 | OAF IID of the object this interface is aggregated to | 
| 
 | Data passed to IO routines. | 
| Returns : | the BonoboPersistFile. | 
BonoboPersistFile * bonobo_persist_file_construct (BonoboPersistFile *pf,BonoboPersistFileIOFn load_fn,BonoboPersistFileIOFn save_fn,const gchar *iid,void *closure);
bonobo_persist_file_construct is deprecated and should not be used in newly-written code.
Initializes the BonoboPersistFile object.  The load_fn and save_fn
parameters might be NULL.  If this is the case, the load and save 
operations are performed by the class load and save methods
| 
 | A BonoboPersistFile | 
| 
 | Loading routine | 
| 
 | Saving routine | 
| 
 | OAF IID of the object this interface is aggregated to | 
| 
 | Data passed to IO routines. | 
| Returns : | the BonoboPersistFile. |