## GdaDictExtend

GdaDictExtend — Make GdaDict manage other types of objects

## Synopsis

                        GdaDictRegisterStruct;
    void                (*GdaDictRegFreeFunc)               (GdaDict *,
                                                             GdaDictRegisterStruct *);
    gboolean            (*GdaDictRegSyncFunc)               (GdaDict *,
                                                             const gchar *limit_object_name,
                                                             GError **);
    GSList*             (*GdaDictRegGetListFunc)            (GdaDict *);
    gboolean            (*GdaDictRegSaveFunc)               (GdaDict *,
                                                             xmlNodePtr ,
                                                             GError **);
    gboolean            (*GdaDictRegLoadFunc)               (GdaDict *,
                                                             xmlNodePtr ,
                                                             GError **);
    GdaObject*          (*GdaDictGetObjFunc)                (GdaDict *,
                                                             const gchar *);
    void                gda_dict_class_always_register      (GdaDictRegFunc func);
    void                gda_dict_register_object_type       (GdaDict *dict,
                                                             GdaDictRegisterStruct *reg);
    GdaDictRegisterStruct* gda_dict_get_object_type_registration
                                                            (GdaDict *dict,
                                                             GType type);

## Description

As provided by libgda, the GdaDict object manages objects related to a database structure (a GdaDictDatabase object) and its environment (data types, functions, etc). However it might be convenient to make the GdaDict object handle arbitrary lists of objects of the same type (provided objects inherit GdaObject).

To "register" a new type of object to a dictionary, all one has to do is create a GdaDictRegisterStruct structure, and call the `gda_dict_register_object_type()` function. It is also possible to make that registration automatic for any new GdaDict object using the `gda_dict_class_always_register()` function.

## Details

### GdaDictRegisterStruct

    typedef struct {
    	/* general information */
    	GType                  type; /* type of object, always valid */
    	gboolean               sort; /* TRUE if lists of objects are sorted by object name */
    	GdaDictRegFreeFunc     free; /* to free @GdaDictRegisterStruct or NULL if just g_free() */

    	/* lists of objects */
    	GSList                *all_objects;
    	GSList                *assumed_objects;

    	/* operations on lists */
    	gchar                 *dbms_sync_key;
    	gchar                 *dbms_sync_descr;
    	GdaDictRegSyncFunc     dbms_sync; /* DBMS sync, or NULL if no sync possible */
    	GdaDictRegGetListFunc  get_objects; /* get the list of objects, or NULL if generic method */
    	GdaDictGetObjFunc      get_by_name; /* get a specific object, or NULL if generic method */

    	/* XML related */
    	const gchar           *xml_group_tag; /* tag for the group of objects in XML file, or NULL if no storage */
    	GdaDictRegSaveFunc     load_xml_tree; /* loading from XML file, or NULL if no loading */
    	GdaDictRegLoadFunc     save_xml_tree; /* saving to XML file, or NULL if no saving*/
    } GdaDictRegisterStruct;

GType `type`; | the GType type of object to register
gboolean `sort`; | TRUE if sorting based on the name of the object (as provided by `gda_object_get_name()`) must be applied when storing objects in the `assumed_objects` list
GdaDictRegFreeFunc `free`; | a function to call when the structure is destroyed, if NULL, then `g_free()` is used
GSList *`all_objects`; | a list of all the objects of this type which have been declared and which are assumed (read only)
GSList *`assumed_objects`; | a list of all the objects of this type which are assumed by the dictionary (read only)
gchar *`dbms_sync_key`; |
gchar *`dbms_sync_descr`; |
GdaDictRegSyncFunc `dbms_sync`; | a function which is called when updating the lists of objects with the database, or NULL if no update is possible
GdaDictRegGetListFunc `get_objects`; | a function to get the list of objects, used by `gda_dict_get_objects()`, or NULL to use default implementation
GdaDictGetObjFunc `get_by_name`; | a function to get an object from its name, used by `gda_dict_get_object_by_name()`, or NULL to use default implementation
const gchar *`xml_group_tag`; | the name of the tag belog which are listed all the objects when saving or loading in an XML file
GdaDictRegSaveFunc `load_xml_tree`; | the function used to save in an XML tree, or NULL if saving not supported
GdaDictRegLoadFunc `save_xml_tree`; | the function used to load from an XML tree, or NULL if loading not supported

### GdaDictRegFreeFunc ()

    void                (*GdaDictRegFreeFunc)               (GdaDict *,
                                                             GdaDictRegisterStruct *);

`Param1` : |
`Param2` : |

### GdaDictRegSyncFunc ()

    gboolean            (*GdaDictRegSyncFunc)               (GdaDict *,
                                                             const gchar *limit_object_name,
                                                             GError **);

`Param1` : |
`limit_object_name` : |
`Param3` : |
Returns : |

### GdaDictRegGetListFunc ()

    GSList*             (*GdaDictRegGetListFunc)            (GdaDict *);

`Param1` : |
Returns : |

### GdaDictRegSaveFunc ()

    gboolean            (*GdaDictRegSaveFunc)               (GdaDict *,
                                                             xmlNodePtr ,
                                                             GError **);

`Param1` : |
`Param2` : |
`Param3` : |
Returns : |

### GdaDictRegLoadFunc ()

    gboolean            (*GdaDictRegLoadFunc)               (GdaDict *,
                                                             xmlNodePtr ,
                                                             GError **);

`Param1` : |
`Param2` : |
`Param3` : |
Returns : |

### GdaDictGetObjFunc ()

    GdaObject*          (*GdaDictGetObjFunc)                (GdaDict *,
                                                             const gchar *);

`Param1` : |
`Param2` : |
Returns : |

### gda_dict_class_always_register ()

    void                gda_dict_class_always_register      (GdaDictRegFunc func);

Make sure all new GdaDict object will use `func` to register a type of object

`func` : | a GdaDictRegFunc function

### gda_dict_register_object_type ()

    void                gda_dict_register_object_type       (GdaDict *dict,
                                                             GdaDictRegisterStruct *reg);

Make `dict` manage objects of type `reg->type`.

`dict` : | a GdaDict object
`reg` : | a GdaDictRegisterStruct structure

### gda_dict_get_object_type_registration ()

    GdaDictRegisterStruct* gda_dict_get_object_type_registration
                                                            (GdaDict *dict,
                                                             GType type);

Get a pointer to the GdaDictRegisterStruct structure for the `type` type of objects.

`dict` : | a GdaDict object
`type` : | e Gtype
Returns : | the GdaDictRegisterStruct pointer, or `NULL` if `type` is not registered