ios - 无法解析协议(protocol)中的类型

Question

#import "MPOContactAuthorizationManager.h"

@protocol MPOContactAuthorizationManagerDelegate <NSObject>

- (void)authorizationManger:(MPOContactAuthorizationManager *)manager
      didUpdateContactState:(ContactsState)contactState;

@end

MPOContactAuthorizationManager 和 ContactState 未解析为类型，即使它们已在 MPOContactAuthorizationManager 中声明:

#import "MPOContactAuthorizationManagerDelegate.h"

typedef enum _contactsState {
    kContactsStateUnknown,
    kContactsStateAllowed,
    kContactsStateDisallowed
} ContactsState;

@interface MPOContactAuthorizationManager : NSObject <UIAlertViewDelegate> {
    ContactsState _contactsAuthorizationState;;
}

@property (strong, nonatomic) NSObject<MPOContactAuthorizationManagerDelegate> *delegate;
@property (nonatomic) ContactsState contactsAuthorizationState;

关于为什么这些没有解决的任何想法？两者都收到错误“Expected a type”

谢谢迈克

Answer 1

你有一个循环依赖。通过删除 #import 行并添加以下内容来更新 MPOContactAuthorizationManagerDelegate.h header :

@class MPOContactAuthorizationManager;

就在 @protocol 行之前。

只需将两者放在一个 .h 文件中(您仍然需要 MPOContactAuthorizationManager 的前向声明):

typedef enum _contactsState {
    kContactsStateUnknown,
    kContactsStateAllowed,
    kContactsStateDisallowed
} ContactsState;

@class MPOContactAuthorizationManager;

@protocol MPOContactAuthorizationManagerDelegate <NSObject>

- (void)authorizationManger:(MPOContactAuthorizationManager *)manager
      didUpdateContactState:(ContactsState)contactState;

@end

@interface MPOContactAuthorizationManager : NSObject <UIAlertViewDelegate> {
    ContactsState _contactsAuthorizationState;;
}

@property (strong, nonatomic) NSObject<MPOContactAuthorizationManagerDelegate> *delegate;
@property (nonatomic) ContactsState contactsAuthorizationState;