0

我正在学习斯坦福的课程，我们为游戏创建了第一个视图控制器，并创建了一个IBOutletCollection类型UIButton来表示卡片。

现在，在讲座中，他创建了一个 setter 方法：

-(void) setCardButtons:(NSArray *)cardButtons {

    _cardButtons = cardButtons;
   [self updateUI];
}

当我评论这种方法并尝试添加更多卡片时，它工作正常。你能解释一下为什么会这样吗？

这是我的 CardGameViewController.m：

#import "CardGameViewController.h"
#import "PlayingCardsDeck.h"
#import "CardMatchingGame.h"


@interface CardGameViewController ()

@property (weak, nonatomic) IBOutlet UILabel *flipsLabel;
@property (weak, nonatomic) IBOutlet UILabel *notificationLabel;
@property (weak, nonatomic) IBOutlet UILabel *scoreCounter;
@property (strong, nonatomic) IBOutletCollection(UIButton) NSArray *cardButtons;

@property (strong, nonatomic) CardMatchingGame *game;
@property (nonatomic) int flipsCount;

@end


@implementation CardGameViewController

//creating the getter method that creates a new card game.
-(CardMatchingGame *) game {

    if (!_game) _game = [[CardMatchingGame alloc] initWithCardCount:self.cardButtons.count usingDeck:[[PlayingCardsDeck alloc] init]];
    return _game;
}

//creating a setter for the IBOutletCollection cardButtons
-(void) setCardButtons:(NSArray *)cardButtons {

    _cardButtons = cardButtons;
   [self updateUI];
}


//creating the setter for the flipCount property. Whick is setting the flipsLabel to the right text and adding the number of counts.
-(void) setFlipsCount:(int)flipsCount {

    _flipsCount = flipsCount;
    self.flipsLabel.text = [NSString stringWithFormat:@"Flips: %d", self.flipsCount];

}


-(void) updateUI {

    for (UIButton *cardButton in self.cardButtons) {
        Card *card = [self.game cardAtIndex:[self.cardButtons indexOfObject:cardButton]];
        [cardButton setTitle:card.contents forState:UIControlStateSelected];
        [cardButton setTitle:card.contents forState:UIControlStateSelected|UIControlStateDisabled];
        cardButton.selected = card.isFaceUp;
        cardButton.enabled = !card.unplayble;
        if (card.unplayble) {
            cardButton.alpha = 0.1;
        }
        self.scoreCounter.text = [NSString stringWithFormat:@"Score: %d", self.game.score];


        if (self.game.notification) {

        self.notificationLabel.text = self.game.notification;

        }

    }
}


//Here I created a method to flipCards when the card is selected, and give the user a random card from the deck each time he flips the card. After each flip i'm incrementing the flipCount setter by one.
- (IBAction)flipCard:(UIButton *)sender {

    [self.game flipCardAtIndex:[self.cardButtons indexOfObject:sender]];
    self.flipsCount++;
    [self updateUI];
}


@end
4

1 回答 1

2

属性获取默认的 setter 和 getter 方法。您可以自己覆盖这些方法以添加功能（[self updateUI];就是这样一个示例）。

当您不指定 setter 或 getter 时，将调用默认的 setter。

于 2013-03-12T02:32:05.120 回答