CODEWITHSUNDEEP
objective-c
MeloS
MeloS

Reputation: 7938

Objective-C: What does getter= actually do in @property?

This code:

@interface SomeClass : NSObject

@property(getter=myProp) NSString *prop;

@end

@implementation AnotherClass

- (void)test {
    SomeClass *s = [[SomeClass alloc] init];
    NSString *x = s.prop;
    NSString *y = s.myProp;
}

@end

Both x and y are the value of the same property, I got two getters, one is -myProp and the other is -prop, so does declaring getter add another getter besides the auto-generated getter?

If this is right, can I use getter= to generate more than one getter?

Also, how do I remove the auto-generated -prop getter?

Upvotes: 0

Views: 39

Answers (1)

iAdjunct
iAdjunct

Reputation: 2999

The @property syntax is really a convenient way to tell Objective-C to synthesize two methods for you:

- (void) setProp:(NSString*)value {
    _prop = value ;
}
- (NSString*) prop {
    return _prop ;
}

Note that, depending on nonatomic vs atomic, it may add threading synchronization in there also.

So, when you write:

NSLog ( object.prop ) ;

You're really writing:

NSLog ( [object prop] ) ;

If you set a getter like you did, it actually creates these methods:

- (void) setProp:(NSString*)value {
    _prop = value ;
}
- (NSString*) myProp {
    return _prop ;
}

So, these two lines:

NSLog ( object.prop ) ; // prop is a property with a getter, so it uses [object myProp]
NSLog ( object.myProp ) ; // myProp isn't a known property, so it assumes it's [object myProp]

Turn in to:

NSLog ( [object myProp] ) ;
NSLog ( [object myProp] ) ;

Upvotes: 2

Related Questions