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shaunsmith
12,145 PointsHow to create a property that belongs to another class
I've tried @property (nonatomic) float ruby;
and I've tried:
#import "Ruby.h"
@interface Bling : NSObject {
@property float ruby;
@end
@interface Gem : NSObject
@end
@interface Ruby : Gem
@end
#import "Ruby.h"
@interface Bling : NSObject {
float ruby;
}
@property float ruby;
@end
1 Answer
Chase Marchione
155,055 PointsHi Shaun,
You want ruby to be a pointer (to give an example of how pointers work: a pointer holds a memory address--thus, creating a pointer allows the programmer to indirectly operate on the data that is stored.)
You'll also want to specify nonatomic and strong for the ruby property. The reasons for doing this are a bit more complex, but to provide generalized reasons as to why we might sometimes do this: Apple's Documentation (https://developer.apple.com/library/mac/documentation/Cocoa/Conceptual/ProgrammingWithObjectiveC/EncapsulatingData/EncapsulatingData.html) specifies that having at least one strong reference helps keep an object alive, and that accessing a nonatomic property is faster of a process than accessing an atomic one (there are reasons to specify atomic, but there's no need to do that here.)
@interface Bling : NSObject
@property (nonatomic, strong) Ruby *ruby;
@end
Hope this helps!