Question

I need to add some codes when MyClass’s string value is changed.
So I’m trying to override a MyClass’s string property method.
But I have no idea.. so I do like following.
Is it correct?

How to override property’s method?

@interface MyClass{
     NSString *string;
}

@property(retain, nonatomic) NSString *string;
@end


@implementation MyClass

- (void)setString:(NSString*)newString{
    // want to add some codes.

    [self setString:newString];  <= Is this correct?
}

@end

Answer 1

- (void)setString:(NSString*)newString{
    // want to add some codes.

    string = newString;  //This is the setter method!
    // You will need to consider memory management etc. 
}

What you are probably more up to is this:

- (void)setString:(NSString*)newString{
    // want to add some codes.

    [super setString:newString];  
}

[self setString:newString] at this place would be a an endless recursive loop. [super setString:newString] should call the superlass’ setter. However, I never did that myself.