Question

I am a newer to objective c. I have read the memory management document on apple’s “Memory Management Rules”. But I am still not very clear about how to manage reference for a property.

What’s the default implementation of set/get access methods for a property declared with “retain” annotation?

This is my assuming, please give some comments. Thanks.

@interface SubClass : NSObject {
NSString * _name;
}
... ...
@property (nonatomic, retain) NSString * name;
... ...
@end

-(NSString *) setName {
   return _name;
}

-(void) setName: (NSString *) pName{
    // the correct version of default set method for retain
    if( _name != pName ) {
        [_name release];
        _name = [pName retain];
    }

}

So the dealloc method, is this ok?

- (void)dealloc {
    self.name = nil; // or [_name release], _name = nil;

}

Answer 1

As Matteo Alessani says, you can simply synthesize the property to get the default implementations.

For reference, this is what’s generated (I got this from reading Objective-C Declared Properties and piecing information together):

- (NSString *)name {
    return _name;
}

- (void)setName:(NSString *)aName {
    if (_name != aName) {
        [_name release];
        _name = [aName retain];
    }
}