设置SwipeGestureRecognizer，需要澄清

Question

我在这里遗漏了一些简单的东西，请帮助我了解一下。

我的控制器设置

UIGestureRecognizer *swipe = [[UIGestureRecognizer alloc] 
          initWithTarget:gameView action:@selector(handleSwipeFrom:)];
[gameView addGestureRecognizer:swipe];

GameView 已设置

@interface GameView : UIView<UIGestureRecognizerDelegate> 

进一步声明

- (IBAction) handleSwipeFrom:(UISwipeGestureRecognizer*)recognizer;

并将其设置为

- (IBAction)handleSwipeFrom:(UISwipeGestureRecognizer*)recognizer {
    NSLog(@" ..............  Swipe detected!! ...................");
}

故事板将UIGestureRecognizer与此IBACtion相关联，设置如下：

我有点担心UIGestureRecognizer出现在Controller下方，而不是显示的视图，但我似乎无法纠正它。

构建应用程序时，无法识别滑动。

请建议我在这里缺少什么，以及我是否正确地进行了设置。

Answer 1

您正在设置两个单独的手势识别器。一个代码可能什么都不做，另一个在故事板中可能没有目标。

在代码中，您应该像这样初始化滑动手势识别器：

UISwipeGestureRecognizer *swipe = [[UISwipeGestureRecognizer alloc] initWithTarget:gameView action:@selector(handleSwipeFrom:)];
 // And assuming the "Up" direction in your screenshot is no accident
swipe.direction = UISwipeGestureRecognizerDirectionUp;

或者，当然，您可以在故事板中连接滑动识别器。通过右键单击手势识别器并将SentActions连接到handleSwipeFrom:方法可以轻松完成此操作，或者类似地，您可以从右侧的连接检查器（如屏幕截图所示）拖动到指定的函数。在图片中，您可以看到我已将Sent Actions连接到方法swipeTarget:。

但目前你有两个不完整的识别器。

Answer 2

-(void)addSwipeEvent:(UIView*)subView{

    UISwipeGestureRecognizer *recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(SwipeRecognizer:)];
    recognizer.numberOfTouchesRequired = 1;
    recognizer.delegate = self;
    [subView addGestureRecognizer:recognizer];
    [recognizer release];

    UISwipeGestureRecognizer *leftRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(SwipeRecognizer:)];
    leftRecognizer.direction=UISwipeGestureRecognizerDirectionLeft;
    leftRecognizer.numberOfTouchesRequired = 1;
    leftRecognizer.delegate = self;
    [subView addGestureRecognizer:leftRecognizer];
    [leftRecognizer release];

    UISwipeGestureRecognizer *downRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(SwipeRecognizer:)];
    downRecognizer.direction=UISwipeGestureRecognizerDirectionDown;
    downRecognizer.numberOfTouchesRequired = 1;
    donwRecognizer.delegate = self;
    [subView addGestureRecognizer:downRecognizer];
    [downRecognizer release];

    UISwipeGestureRecognizer *upRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(SwipeRecognizer:)];
    upRecognizer.direction=UISwipeGestureRecognizerDirectionUp;
    upRecognizer.numberOfTouchesRequired = 1;
    upRecognizer.delegate = self;
    [subView addGestureRecognizer:upRecognizer];
    [upRecognizer release];
}

- (void) SwipeRecognizer:(UISwipeGestureRecognizer *)sender {
    if ( sender.direction == UISwipeGestureRecognizerDirectionLeft ){
        NSLog(@" *** SWIPE LEFT ***");

    }
    if ( sender.direction == UISwipeGestureRecognizerDirectionRight ){
        NSLog(@" *** SWIPE RIGHT ***");

    }
    if ( sender.direction== UISwipeGestureRecognizerDirectionUp ){
        NSLog(@" *** SWIPE UP ***");

    }
    if ( sender.direction == UISwipeGestureRecognizerDirectionDown ){
        NSLog(@" *** SWIPE DOWN ***");

    }
}


- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
    if ([touch.view isKindOfClass:[UIView class]])
    {
        return YES;
    }
    return NO;
}

Answer 3

    UISwipeGestureRecognizer *swipe = [[UISwipGestureRecognizer alloc] 
      initWithTarget:gameView action:@selector(handleSwipeFrom:)];
    [gameView addGestureRecognizer:swipe];


- (IBAction)handleSwipeFrom:(UISwipeGestureRecognizer*)recognizer {
    NSLog(@" ..............  Swipe detected!! ...................");
}

然后撤消你在IB中所做的事情。如果你在代码中执行它，那么在IB中执行它也只是复制工作，并且可能会加倍滑动处理的次数