Objective-C的狀態機傳遞參數

Question

我感興趣這篇文章讀來的StackOverflow： How to Make a Basic Finite State Machine in Objective-C

我就以此爲基礎建立我的狀態機進行簡單的足球比賽。我有狀態保衛，進攻，暫停，中立。我已經創建了狀態機，它將打印出NSLog「現在進入狀態保衛」等。

現在我想通過一個參考我的足球隊到狀態機，這樣我可以讓我的球隊根據國家做一些事情。也就是說，如果它的防守，我可以讓我的球員站在對手旁邊。

我試過很多不同的方法，但都以語法錯誤結束。 ID欣賞在正確的方向

推TeamState.h注意錯誤即時得到的意見

@class TeamState; 

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

@protocol TeamStateProt 

-(void) enterTeamState:(TeamState*)team; 
-(void) executeTeamState:(TeamState*)team; 
-(void) exitTeamState:(TeamState*)team; 

@end 


@interface TeamState : NSObject{ 
    id<TeamStateProt> currentTeamState; 

    id<TeamStateProt> Stoppage; 
    id<TeamStateProt> Neutral; 
    id<TeamStateProt> Defend; 
    id<TeamStateProt> Attack; 

    FootballTeam *footballTeam; //ERROR Unknown Type name FootballTeam 
} 

@property (nonatomic, retain) id<TeamStateProt> currentTeamState; 
@property (nonatomic, retain) id<TeamStateProt> Stoppage; 
@property (nonatomic, retain) id<TeamStateProt> Neutral; 
@property (nonatomic, retain) id<TeamStateProt> Defend; 
@property (nonatomic, retain) id<TeamStateProt> Attack; 

- (id)initWithFootBallTeam:(FootballTeam*) team; //Error Expected a Type 
-(void)update; 
-(void)changeState:(id<TeamStateProt>) newState; 
-(void)executeState:(id<TeamStateProt>) State; 
@end 

TeamState.m

#import "TeamState.h" 
#import "FootballTeam.h" 
#import "Stoppage_TS.h" 
#import "Neutral_TS.h" 
#import "Defend_TS.h" 
#import "Attack_TS.h" 


@implementation TeamState 

@synthesize currentTeamState; 
@synthesize Stoppage, Neutral, Defend, Attack; 

- (id)init 
{ 
    self = [super init]; 
    if (self) { 
     // Initialization code here. 
     id<TeamStateProt> s = [[Stoppage_TS alloc] init]; 
     self.Stoppage = s; 

     id<TeamStateProt> n = [[Neutral_TS alloc] init]; 
     self.Neutral = n; 

     id<TeamStateProt> d = [[Defend_TS alloc] init]; 
     self.Defend = d; 

     id<TeamStateProt> a = [[Attack_TS alloc] init]; 
     self.Attack = a; 

     self.currentTeamState = n; 
     [self.currentTeamState enterTeamState:self]; 
     [self executeState:self.currentTeamState]; 
    } 

    return self; 
} 

- (id)initWithFootBallTeam:(FootballTeam*) team 
{ 
    self = [super init]; 
    if (self) { 
     // Initialization code here. 
     id<TeamStateProt> s = [[Stoppage_TS alloc] init]; 
     self.Stoppage = s; 


     id<TeamStateProt> n = [[Neutral_TS alloc] init]; 
     self.Neutral = n; 

     id<TeamStateProt> d = [[Defend_TS alloc] init]; 
     self.Defend = d; 

     id<TeamStateProt> a = [[Attack_TS alloc] init]; 
     self.Attack = a; 

     self.currentTeamState = n; 
     [self.currentTeamState enterTeamState:self]; 
     [self executeState:self.currentTeamState]; 

     footballTeam = team; 
    } 

    return self; 
} 

-(void)changeState:(id<TeamStateProt>) newState{ 
    NSLog(@"Changing State"); 
    if (newState != nil) { 
     NSLog(@"Changing a state which isn't nil"); 
     [self.currentTeamState exitTeamState:self]; 
     self.currentTeamState = newState; 
     [self.currentTeamState enterTeamState:self]; 
     [self executeState:self.currentTeamState]; 
    } 

} 

-(void)executeState:(id<TeamStateProt>) State{ 
    [self.currentTeamState executeTeamState:self]; 
} 

// Each update, execute the execute state on the current team state 
-(void)update{ 
    [self executeState:self.currentTeamState]; 
} 
@end 

FootballTeam.h

#import <Foundation/Foundation.h> 
#import "Player.h" 
#import "TeamState.h" 
#import "Football.h" 

typedef enum { 
    Home, 
    Away 
} TeamType; 

@interface FootballTeam : NSObject{ 
    Player *ReceivingPlayer; //Player to receive the ball 
    Player *ClosestToBall;  //Player closest to the ball 
    Player *ControllingPlayer; //Player who has the ball can be NULL 
    Player *SupportingPlayer; //Player in a position to receive the ball 

    NSMutableArray *players; //Array of all the Players on this team 

    TeamState *state;   //Current state of the teams state machine 

    TeamType type;    //Defines if Home team or Away team 
} 

@property (nonatomic) TeamType type; 
@property(nonatomic, retain) TeamState *state; 

-(void) sendPlayersToHome; 
-(Player*) playerClosestToBall:(Football*) ball; 
-(BOOL) areAllPlayersAtHome; 

@end 

Answer 1

你有循環引用。你在FootballTeam.h中導入TeamState.h，反之亦然。

爲避免這種情況，只能將.h文件導入到.m文件中，並在.h文件中添加前向聲明。

所以，在TeamState.h：

@class FootballTeam; 

並移動進口TeamState.m

在FootballTeam一樣。