OBJ-C繼承變量是空

Question

我有有一個自定義init方法，然後通過使用init方法傳入的值，然後調用它的子類定製的初始化方法的基類。問題是當我試圖訪問有分配給它們通過子類的基類通過super值的變量，該值是零，它像基類是完全不同的對象。是否因爲基類尚未從其init方法返回？還是我在這裏繼承了錯誤的方式？代碼要遵循。

接口

@interface WTFGameBoard : NSObject 
{ 
    @protected 
    UIView *_answerView; 
    UIView *_keyboardView; 
    NSMutableArray* _answerSeperatedByCharacter; 

    WTFAnswerBoard *_answerBoard; 
    WTFGameKeyboard *_gameKeyboard; 

    OpenGameViewController *_weakGameViewRef; 
    GameInfo *_gameinfo; 
} 

-(id) initWithGameVC:(OpenGameViewController*)gameVC; 

@property (nonatomic,unsafe_unretained)OpenGameViewController *weakGameViewRef; 
@property (nonatomic,strong)GameInfo *gameInfo; 

@end 

實施

@implementation WTFGameBoard 
@synthesize weakGameViewRef = _weakGameViewRef; 
@synthesize gameInfo = _gameinfo; 

-(id) initWithGameVC:(OpenGameViewController*)gameVC 
{ 
    if (self = [super init]) 
    { 
     //[weakGameViewRef ] 
     _answerView = [gameVC answerView]; 
     _keyboardView = [gameVC keyboardView]; 

     self.weakGameViewRef = gameVC; 
     self.gameInfo = [[CurrentGamesInfo sharedCurrentGamesInfo]_selectedGame]; 

     _answerBoard = [[WTFAnswerBoard alloc] initWithAnswer:[gameVC answer] blankSpaceImageView:[gameVC answerBox]]; 
     _gameKeyboard = [[WTFGameKeyboard alloc] initWithButtons:[gameVC letterSelectButtons]]; 

    } 

    return self; 
} 

@end 

接口

@interface WTFAnswerBoard : WTFGameBoard 
{ 
    NSMutableArray *WTFAnswerSpaces; 
    NSMutableArray *_answerBlankBlocks; 
    NSMutableArray *_answerGiven; 
    NSMutableArray *_answerBlankOriginalPosition; 
    NSString *_answer; 
} 

-(id)initWithAnswer:(NSString*)answer blankSpaceImageView:(UIImageView*)answerBox; 

實施

-(id)initWithAnswer:(NSString*)answer blankSpaceImageView:(UIImageView*)answerBox 
{ 
    if (self = [super init]) 
    { 
     _weakGameViewRef = [super weakGameViewRef];//WHY U NO NOT BE NULL? 
     _gameinfo = [super gameInfo];//WHY U NO NOT BE NULL? 

     _answerBlankBlocks = [_weakGameViewRef answerBlankBlocks]; 
     _answerGiven = [_weakGameViewRef answerGiven]; 
     _answerBlankOriginalPosition = [_weakGameViewRef answerBlankOriginalPosition]; 

     [self SetupBlankAnswerSpacesForAnswer:answer withTemplate:answerBox]; 
    } 

    return self; 
} 

Answer 1

問題是，你是不是調用在派生類中的自定義構造函數：

if (self = [super init]) 

要調用默認的，這是不覆蓋，而沒有按」 t初始化您嘗試訪問的ivars。

你應該打電話給你的自定義構造函數：

if (self = [super initWithGameVC:gameVC]) 

當然，這意味着你需要沿着參數傳遞，或者通過初始化你想，而不需要任何參數進行初始化什麼覆蓋默認的構造函數。

，我不understant另一件事就是爲什麼你在你的自定義類設置的派生類的實例變量：

_weakGameViewRef = [super weakGameViewRef]; 

這基本上什麼也不做，因爲伊娃是一樣的，如果你設置了一個你的基類可以直接訪問它。

編輯

既然你這裏有一個奇怪的依賴問題的快速解決辦法是有一些像

WTFAnswerBoard initWithWTFGameBoard:(WTFGameBoard*)board { 
    self.board = board; 
} 

這樣您就可以訪問該實例化WTFAnswerBoard板，並保持繼承，但切換用法組成（讓你的遞歸初始化不會發生添加屬性WTFAnswerBoard。