Functions | |
EAPI void | evas_object_data_set (Evas_Object *obj, const char *key, const void *data) |
Set an attached data pointer to an object with a given string key. | |
EAPI void * | evas_object_data_get (Evas_Object *obj, const char *key) |
Return an attached data pointer by its given string key. | |
EAPI void * | evas_object_data_del (Evas_Object *obj, const char *key) |
Delete at attached data pointer from an object. |
EAPI void* evas_object_data_del | ( | Evas_Object * | obj, | |
const char * | key | |||
) |
Delete at attached data pointer from an object.
obj | The object to delete the data pointer from | |
key | The string key the data was stored under |
key
on obj
obj
stored under key
, and return the original pointer stored under key
, if any, nor NULL if nothing was stored under that key.Example:
int *my_data; extern Evas_Object *obj; my_data = evas_object_data_del(obj, "name_of_my_data");
EAPI void* evas_object_data_get | ( | Evas_Object * | obj, | |
const char * | key | |||
) |
Return an attached data pointer by its given string key.
obj | The object to which the data was attached | |
key | The string key the data was stored under |
obj
stored using the string key key
. If the object is valid and data was stored under the given key, the pointer that was stored will be reuturned. If this is not the case, NULL will be returned, signifying an invalid object or non-existent key. It is possible a NULL pointer was stored given that key, but this situation is non-sensical and thus can be considered an error as well. NULL pointers are never stored as this is the return value if an error occurs.Example:
int *my_data; extern Evas_Object *obj; my_data = evas_object_data_get(obj, "name_of_my_data"); if (my_data) printf("Data stored was %p\n", my_data); else printf("No data was stored on the object\n");
EAPI void evas_object_data_set | ( | Evas_Object * | obj, | |
const char * | key, | |||
const void * | data | |||
) |
Set an attached data pointer to an object with a given string key.
obj | The object to attach the data pointer to | |
key | The string key for the data to access it | |
data | The ponter to the data to be attached |
data
to the object obj
given the string key
. This pointer will stay "hooked" to the object until a new pointer with the same string key is attached with evas_object_data_set() or it is deleted with evas_object_data_del(). On deletion of the object obj
, the pointers will not be accessible from the object anymore.
You can find the pointer attached under a string key using evas_object_data_get(). It is the job of the calling application to free any data pointed to by data
when it is no longer required.
If data
is NULL, the old value stored at key
will be removed but no new value will be stored. This is synonymous with calling evas_object_data_del() with obj
and key
.
Example:
int *my_data; extern Evas_Object *obj; my_data = malloc(500); evas_object_data_set(obj, "name_of_data", my_data); printf("The data that was attached was %p\n", evas_object_data_get(obj, "name_of_data"));