Question

I’m using the following lines to declare a property in my objective-c program.

@property (retain) int Money;

and the syntesize in my implementation file.

Now i wanted to make an addMoney method in my implementation to add an amount of money in my program. I was typing addMoney when i realized that Xcode was saying there is always a method with this name that i could override. It has the following signature.

-(void)addMoney:(NSSet *)objects;

and

-(void)addMoneyObject:(object-type *)object

where do they come from and who is calling them? AND how could i use it by myself? What must i attend to when using this?

Answer 1

This method does not actually exist. Xcode is helping you out by completing some common naming patterns. It’s somewhat common to have a situation like this:

@class Thing;
@property (nonatomic, retain) NSMutableSet *things;

- (void)addThings:(NSSet *)someThings;
- (void)addThing:(Thing *)aThing;

Xcode is just trying to make it a little easier to type that. But the methods don’t really exist unless you create them.

Side note: you can’t retain an int, so I assume this isn’t real code. That’s fine. Do make sure your properties start with a leading lowercase (money). It’s not just individual style. ObjC relies on Key-Value Coding for many things. That requires that things be named in a certain way or it won’t work.