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iOS Objective-C Basics (Retired) Introduction to Objective-C Inheritance

Posted by bryan dubay
bryan dubay
528 Points

declaration of a class in .h file. objective-c

declare class ib1

Gem.h 
@interface Gem : NSObject

@end
Ruby.h 
@interface Ruby : Gem
@end
Bling.h 
@interface Bling : NSObject
@class Ruby
@property (nonatomic,strong) Ruby *ruby;

@end

1 Answer

Matt Faber
Matt Faber
9,156 Points
Matt Faber
Matt Faber
9,156 Points

Forward class declarations like @class Ruby should be placed before your interface declaration @interface Bling : NSObject, otherwise the you will get in an illegal interface qualifier error.

Your Bling.h file should look like the following.

@class Ruby;

@interface Bling : NSObject

@property (nonatomic,strong) Ruby *ruby;

@end