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Libgnomedb Reference Manual | ![]() |
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enum GnomeDbRefBaseType; GnomeDbRefBase; GType gnome_db_ref_base_get_type (void); GObject* gnome_db_ref_base_new (GnomeDbDict *dict); GObject* gnome_db_ref_base_new_no_ref_count (GnomeDbDict *dict); GObject* gnome_db_ref_base_new_copy (GnomeDbRefBase *orig); void gnome_db_ref_base_set_ref_name (GnomeDbRefBase *ref, GType ref_type, GnomeDbRefBaseType type, const gchar *name); const gchar* gnome_db_ref_base_get_ref_name (GnomeDbRefBase *ref, GType *ref_type, GnomeDbRefBaseType *type); GType gnome_db_ref_base_get_ref_type (GnomeDbRefBase *ref); void gnome_db_ref_base_set_ref_object (GnomeDbRefBase *ref, GnomeDbBase *object); void gnome_db_ref_base_set_ref_object_type (GnomeDbRefBase *ref, GnomeDbBase *object, GType type); void gnome_db_ref_base_replace_ref_object (GnomeDbRefBase *ref, GHashTable *replacements); GnomeDbBase* gnome_db_ref_base_get_ref_object (GnomeDbRefBase *ref); gboolean gnome_db_ref_base_activate (GnomeDbRefBase *ref); void gnome_db_ref_base_deactivate (GnomeDbRefBase *ref); gboolean gnome_db_ref_base_is_active (GnomeDbRefBase *ref);
"ref-found" void user_function (GnomeDbRefBase *dbrefbase, gpointer user_data) : Run first "ref-lost" void user_function (GnomeDbRefBase *dbrefbase, gpointer user_data) : Run first
This object is a simple wrapper to reference other objects. It can be used in places where referenced objects do not yet exist when they are needed, and their xml ID or their name is known. In this situation, create a GnomeDbRefBase object, give it the xml ID or name of the object which is to be referenced, and activate the GnomeDbRefBase object. If it is activated, then the real object can be fetched through the GnomeDbRefBase object.
There are restrictions on the types of objects which can be handled:
GnomeDbField (for any GnomeDbTableField of GnomeDbQfield object)
GObject* gnome_db_ref_base_new (GnomeDbDict *dict);
Creates a new GnomeDbRefBase object. This GnomeDbRefBase object does itself increase the
reference count of the referenced object, so if all the reference count holders call g_object_unref()
on there referenced object, then that object will not be destroyed because this GnomeDbRefBase still
has a reference on it. Use gnome_db_ref_base_new_no_ref_count()
if you don't want to increase the reference
count of the referenced object.
dict : |
a GnomeDbDict object |
Returns : | the new object |
GObject* gnome_db_ref_base_new_no_ref_count (GnomeDbDict *dict);
Creates a new GnomeDbRefBase object. This GnomeDbRefBase object does not
itself increase the reference count of the object it keeps a reference to,
which means that if all the reference count holders call g_object_unref()
on there referenced object, then that object will actually be destroyed
and a "ref_lost" signal will be emitted. Use gnome_db_ref_base_new()
if you want to
increase the count of the referenced object.
dict : |
a GnomeDbDict object |
Returns : | the new object |
GObject* gnome_db_ref_base_new_copy (GnomeDbRefBase *orig);
Creates a new GnomeDbRefBase object which is a copy of orig
. This is a copy constructor.
orig : |
a GnomeDbRefBase object |
Returns : | the new object |
void gnome_db_ref_base_set_ref_name (GnomeDbRefBase *ref, GType ref_type, GnomeDbRefBaseType type, const gchar *name);
Sets the type and XML Id of the object we want to reference. If any other object was already
referenced ref
is first reinitialized
Rem: the name format is dependant on the type of object which is requested
ref : |
a GnomeDbRefBase object |
ref_type : |
the requested referenced object's data type, or 0 if not specified and type = REFERENCE_BY_XML_ID
|
type : |
how to interpret the name argument
|
name : |
the name of the requested object |
const gchar* gnome_db_ref_base_get_ref_name (GnomeDbRefBase *ref, GType *ref_type, GnomeDbRefBaseType *type);
Get the caracteristics of the requested object
ref : |
a GnomeDbRefBase object |
ref_type : |
where to store the requested referenced object's data type, or NULL |
type : |
where to store how to interpret the returned name, or NULL |
Returns : | the name of the object (to be interpreted with type )
|
GType gnome_db_ref_base_get_ref_type (GnomeDbRefBase *ref);
Get the type of the referenced object by ref
(or the requested type if ref
is not active)
ref : |
a GnomeDbRefBase object |
Returns : | the type |
void gnome_db_ref_base_set_ref_object (GnomeDbRefBase *ref, GnomeDbBase *object);
Rather than to set the XML Id of the object ref
has to reference, this function allows
to directly give the object, in case the object is known.
ref : |
a GnomeDbRefBase object |
object : |
the object to keep a reference to |
void gnome_db_ref_base_set_ref_object_type (GnomeDbRefBase *ref, GnomeDbBase *object, GType type);
Rather than to set the XML Id of the object ref
has to reference, this function allows
to directly give the object, and specify the requested type, in case the object is known.
ref : |
a GnomeDbRefBase object |
object : |
the object to keep a reference to |
type : |
the type of object requested: it must be a type in the class hierarchy of object
|
void gnome_db_ref_base_replace_ref_object (GnomeDbRefBase *ref, GHashTable *replacements);
Changes the referenced object with a new one: it looks into replacements
and if the
currently referenced object appears there as a key, then the reference is replaced with
the corresponding value.
Nothing happens if ref
is not active, or if the referenced object is not found in replacaments
.
ref : |
a GnomeDbRefBase object |
replacements : |
a GHashTable |
GnomeDbBase* gnome_db_ref_base_get_ref_object (GnomeDbRefBase *ref);
Get the referenced object by ref
ref : |
a GnomeDbRefBase object |
Returns : | a pointer to the object, or NULL if the reference is not active |
gboolean gnome_db_ref_base_activate (GnomeDbRefBase *ref);
Tries to "activate" a reference (to find the referenced object). Nothing happens if the object is already activated
ref : |
a GnomeDbRefBase object |
Returns : | TRUE on success |
void gnome_db_ref_base_deactivate (GnomeDbRefBase *ref);
Desctivates the object (loses the reference to the object)
ref : |
a GnomeDbRefBase object |
gboolean gnome_db_ref_base_is_active (GnomeDbRefBase *ref);
Find wether ref
is active
ref : |
a GnomeDbRefBase object |
Returns : | TRUE if ref is active
|
void user_function (GnomeDbRefBase *dbrefbase, gpointer user_data) : Run first
dbrefbase : |
the object which received the signal. |
user_data : |
user data set when the signal handler was connected. |
void user_function (GnomeDbRefBase *dbrefbase, gpointer user_data) : Run first
dbrefbase : |
the object which received the signal. |
user_data : |
user data set when the signal handler was connected. |