properties - purpose of @property in objective c -

look below code;

@interface testviewcontroller : uiviewcontroller {      int age;      uipopovercontroller *popovercontroller; } @property (nonatomic , retain ) int age; @property (nonatomic , retain ) uipopovercontroller *popovercontroller;  @end 

@property (nonatomic , retain ) int age defines getters , setters int age; , @synthesizing them in implemetation gives autogenerated implementation of getter , setter.

what dont understand second one. methods second property (@property (nonatomic , retain ) uipopovercontroller *popovercontroller;) generate? (:

i have seen lot of programs use @property objects apart int, string etc;

can guide me proper tutorial this.

thanks in advance. (also can tell me how accept answers on stackoverflow).

it difficult advise better official documentation (at least should start reading it).

@property (nonatomic , retain ) int age; 

is supposed declare setter/getter methods age ivar, line give compiler error can't declare property retain attribute non-object types (see docs more details)

@property (nonatomic , retain ) uipopovercontroller *popovercontroller; 

this line not differ 1st 1 - declares setter , getter methods popovercontroller ivar, , automatically synthesized setter retain popovercontroller gets