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Typedef update / extension defined in the Objective-C protocol in the class corresponding to the protocol

I have an Objective-C protocol:

typedef enum {
    ViewStateNone
} ViewState;

@protocol ViewStateable

- (void)initViewState:(ViewState)viewState;
- (void)setViewState:(ViewState)viewState;

@end

I use this protocol in the following class:

#import "ViewStateable.h"

typedef enum {
    ViewStateNone,
    ViewStateSummary,
    ViewStateContact,
    ViewStateLocation
} ViewState;

@interface ViewController : UIViewController <ViewStateable> {

}

@end

I will not go too far into the specification of my application, but what I am doing here is an typedefenumeration in the protocol so that the protocol methods can accept an input value of this type.

Then I hoped to update or extend this typedef in classes that conform to this protocol so that each class can have its own view states. However, I encountered two of the following errors:

  • Redeclaration of enumerator 'ViewStateNone'
  • Conflicting types for 'ViewState'

I am ashamed to admit that my knowledge of C (namely typedefs) is not extensive, and here is what I am trying to do here, firstly, perhaps, and secondly, reasonably?

Greetings from friends.

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  ViewStateNone
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#define ViewStateNone 1

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