Name
BonoboPersistStream -- Interface for anything that can save / load itself from a Bonobo stream.
Synopsis
struct BonoboPersistStream;
void (*BonoboPersistStreamIOFn) (BonoboPersistStream *ps,
const Bonobo_Stream stream,
Bonobo_Persist_ContentType type,
void *closure,
CORBA_Environment *ev);
CORBA_long (*BonoboPersistStreamMaxFn) (BonoboPersistStream *ps,
void *closure,
CORBA_Environment *ev);
Bonobo_Persist_ContentTypeList* (*BonoboPersistStreamTypesFn)
(BonoboPersistStream *ps,
void *closure,
CORBA_Environment *ev);
typedef BonoboPersistStreamClass;
void bonobo_persist_stream_set_dirty (BonoboPersistStream *ps,
gboolean dirty);
BonoboPersistStream* bonobo_persist_stream_new
(BonoboPersistStreamIOFn load_fn,
BonoboPersistStreamIOFn save_fn,
BonoboPersistStreamMaxFn max_fn,
BonoboPersistStreamTypesFn types_fn,
void *closure);
BonoboPersistStream* bonobo_persist_stream_construct
(BonoboPersistStream *ps,
BonoboPersistStreamIOFn load_fn,
BonoboPersistStreamIOFn save_fn,
BonoboPersistStreamMaxFn max_fn,
BonoboPersistStreamTypesFn types_fn,
void *closure);
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Description
The PersistStream interface is the interface to use for all new
components that are able to load and save themselves to a stream.
It should be associated with any BonoboEmbeddable for use by the
container in creating a compound document.
This interface works by connecting callbacks to the methods, in
a somewhat 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 1. Implementing the PersistStream callbacks
static void
load_from_stream (BonoboPersistStream *ps,
const Bonobo_Stream stream,
Bonobo_Persist_ContentType type,
void *closure,
CORBA_Environment *ev)
{
EogImageData *image_data = closure;
g_warning ("Load content from stream of type 's'", type);
}
static gint
save_to_stream (BonoboPersistStream *ps,
const Bonobo_Stream stream,
Bonobo_Persist_ContentType type,
void *closure,
CORBA_Environment *ev)
{
EogImageData *image_data = closure;
g_warning ("Save content to stream with type 's'", type);
}
static Bonobo_Persist_ContentTypeList *
get_supported_types (BonoboPersistStream *ps,
void *closure,
CORBA_Environment *ev)
{
return bonobo_persist_generate_content_types (
2, "text/plain", "text/html");
}
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Having implemented the callbacks we then have to register them
and aggregate the interface to our object:
Example 2. Aggregating a new PersistStream
EogImageData *
eog_image_data_construct (EogImageData *image_data)
{
BonoboObject *retval;
BonoboPersistStream *ps;
ps = bonobo_persist_stream_new (
load_from_stream, save_to_stream,
get_supported_types, NULL,
image_data);
if (ps == NULL) {
bonobo_object_unref (BONOBO_OBJECT (image_data));
return NULL;
}
bonobo_object_add_interface (BONOBO_OBJECT (image_data),
BONOBO_OBJECT (ps));
return image_data;
}
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Details
struct BonoboPersistStream
struct BonoboPersistStream; |
BonoboPersistStreamIOFn ()
void (*BonoboPersistStreamIOFn) (BonoboPersistStream *ps,
const Bonobo_Stream stream,
Bonobo_Persist_ContentType type,
void *closure,
CORBA_Environment *ev); |
BonoboPersistStreamMaxFn ()
CORBA_long (*BonoboPersistStreamMaxFn) (BonoboPersistStream *ps,
void *closure,
CORBA_Environment *ev); |
BonoboPersistStreamTypesFn ()
Bonobo_Persist_ContentTypeList* (*BonoboPersistStreamTypesFn)
(BonoboPersistStream *ps,
void *closure,
CORBA_Environment *ev); |
BonoboPersistStreamClass
typedef struct {
BonoboPersistClass parent_class;
POA_Bonobo_PersistStream__epv epv;
/* methods */
void (*load) (BonoboPersistStream *ps,
Bonobo_Stream stream,
Bonobo_Persist_ContentType type,
CORBA_Environment *ev);
void (*save) (BonoboPersistStream *ps,
Bonobo_Stream stream,
Bonobo_Persist_ContentType type,
CORBA_Environment *ev);
CORBA_long (*get_size_max) (BonoboPersistStream *ps,
CORBA_Environment *ev);
Bonobo_Persist_ContentTypeList * (*get_content_types) (BonoboPersistStream *ps,
CORBA_Environment *ev);
} BonoboPersistStreamClass; |
bonobo_persist_stream_set_dirty ()
void bonobo_persist_stream_set_dirty (BonoboPersistStream *ps,
gboolean dirty); |
This routine sets the dirty bit for the PersistStream object.
bonobo_persist_stream_new ()
Creates a new BonoboPersistStream object. The various operations
for the object are performed by the provided callback functions,
which are passed closure when they are invoked. If any callback is
NULL, the corresponding operation is performed by the class load
and save routines.
bonobo_persist_stream_construct ()
Initializes the BonoboPersistStream object. The load and save
operations for the object are performed by the provided load_fn
and save_fn callback functions, which are passed closure when
they are invoked. If either load_fn or save_fn is NULL, the
corresponding operation is performed by the class load and save
routines.