Objective-C error "No visible @interface for 'XYZPerson' declares the selector 'saySomething'

Question

I am really new to Objective-C and when I was practicing the book exercises, I really am stuck here. Please help me solve this and I have been thinking what could cause thi

Answer 1

It looks like you are testing inheritance so I will assume that XYZShout is supposed to be derived from XYZPerson. If so follow the suggestion from @JFS and make sure it does actually derive:

XYZShout.h:

#import 
#import "XYZPerson.h"

@interface XYZShout : XYZPerson

- (void)saySomething:(NSString *)greet;

@end

And also correct the definition of saySomething in XYZPerson (you missed off the parameter):

XYZPerson.h:

#import 
@interface XYZPerson : NSObject

@property NSString *firstName;
@property NSString *secondName;
@property NSDate *dob;

- (void)saySomething:(NSString *)greet;
//                   ^^^^^^^^^^^^^^^^^
- (void)sayHello;

@end