xcode 未知类型名称

Question

我得到了这样的代码：

Match.h：

#import <Foundation/Foundation.h>
#import "player.h"

@interface Match : NSObject
{
    Player *firstPlayer;
}

@property (nonatomic, retain) Player *firstPlayer;

@end

播放器.h：

#import <Foundation/Foundation.h>
#import "game.h"
@interface Player : NSObject
{
}

- (Player *) init;

//- (NSInteger)numberOfPoints;
//- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil;


@property (nonatomic, retain) NSString *name;
@property (nonatomic, retain) NSString *surname;
@property (nonatomic, assign) NSInteger *player_id;
@property (nonatomic, retain) NSString *notes;

@end

游戏.h：

#import <Foundation/Foundation.h>
#import "match.h"
#import "player.h"

@interface Game : NSObject
{
    NSMutableArray *matches;
    NSMutableArray *players;
    NSString *name;
}

-(Game *) init;

@property (nonatomic, retain) NSMutableArray *matches;
@property (nonatomic, retain) NSMutableArray *players;
@property (nonatomic, retain) NSString *name;

@end

当我声明 *firstPlayer 时，Xcode 不会编译我的项目并向我显示 Match.h 中的错误 unknown type 'Player'。

我尝试清理项目，重建它但没有任何结果......

Answer 1

解决这个循环的正常方法是转发声明类：

在 Match.h 中：

@class Player;
@interface Match ...
    Player * firstPlayer;

并且只在 Match.m 中执行 #import "Player.h，在 Match.h 中执行 not

其他两个 .h 文件也是如此。