Answer 1

好像有一个bug。您可以像指定的那样指定允许的方向。但是当您尝试访问动作选择器方法中触发滑动的实际方向时，您仍然会获得最初设置的位掩码（对于允许的方向）。

这意味着当允许超过1个方向时，检查实际方向将始终失败。 当你在选择器方法中输出'direction'的值时，你可以很容易地看到它（即-(void)scrollViewSwiped:(UISwipeGestureRecognizer *)recognizer）。

向Apple提交了一份错误报告（＃8276386）。

[更新]我从Apple那里得到了一个答案，说这个行为符合预期。

因此，例如在表格视图中，您可以在表格视图单元格中向左或向右滑动以触发“删除”（这会将滑动手势的方向设置为左右）

这意味着原始的解决方法是它应该被使用的方式。 direction属性只能用于正确识别手势，但不能用于成功识别时执行的方法，以比较触发识别的实际方向。

Answer 2

我注意到左/右和上/下手势成对一起工作，因此您只需要指定两个手势识别器。而且文档似乎确实是错误的。

Answer 3

那太糟糕了，我通过添加Lars提到的两个手势解决了这个问题，并且完美运行......

1）左/右 2）上/下

  

UISwipeGestureRecognizer *swipeLeftRight = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleGesture:)];
    [swipeLeftRight setDirection:(UISwipeGestureRecognizerDirectionRight | UISwipeGestureRecognizerDirectionLeft )];
    [self.view addGestureRecognizer:swipeLeftRight];

    UISwipeGestureRecognizer *swipeUpDown = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleGesture:)];
    [swipeUpDown setDirection:(UISwipeGestureRecognizerDirectionUp | UISwipeGestureRecognizerDirectionDown )];
    [self.view addGestureRecognizer:swipeUpDown];

Answer 4

UISwipeGestureRecognizer *recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(didSwipe:)];
[recognizer setDirection:(UISwipeGestureRecognizerDirectionRight)];
[self.view addGestureRecognizer:recognizer];
[recognizer release];

recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(didSwipe:)];
[recognizer setDirection:(UISwipeGestureRecognizerDirectionLeft)];
[self.view addGestureRecognizer:recognizer];
[recognizer release];

现在这是didSwipe函数

- (void) didSwipe:(UISwipeGestureRecognizer *)recognizer{
      if([recognizer direction] == UISwipeGestureRecognizerDirectionLeft){
          //Swipe from right to left
          //Do your functions here
      }else{
          //Swipe from left to right
          //Do your functions here
      }
 }

Answer 5

如果你使用Xcode 4.2，你可以在故事板上添加Gesture Recognizers，然后将GUI手势识别器链接到IBActions。

您可以在效用窗格的对象库中找到手势识别器（右侧窗格的底部）。

然后它只是一个控制问题 - 拖动到适当的行动。

Answer 6

如果您希望它检测所有四个方向，您需要创建四个实例，就像您在解决方法中所做的那样。

这是为什么： 您创建的UISwipeGestureRecognizer的相同实例是作为发送方传递给选择器的实例。因此，如果您将其设置为识别所有四个方向，则sgr.direction == xxx将返回true，其中xxx是四个方向中的任何一个。

这是一个替代解决方案，涉及更少的代码（假设使用ARC）：

for(int d = UISwipeGestureRecognizerDirectionRight; d <= UISwipeGestureRecognizerDirectionDown; d = d*2) {
    UISwipeGestureRecognizer *sgr = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleSwipeFrom:)];
    sgr.direction = d;
    [self.view addGestureRecognizer:sgr];
}

Answer 7

以下是UISwipeGestureRecognizer用法的代码示例。注意评论。

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    //add gesture recognizer. The 'direction' property of UISwipeGestureRecognizer only sets the allowable directions. It does not return to the user the direction that was actaully swiped. Must set up separate gesture recognizers to handle the specific directions for which I want an outcome.
    UISwipeGestureRecognizer *gestureRight;
    UISwipeGestureRecognizer *gestureLeft;
    gestureRight = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(swipeRight:)];//direction is set by default.
    gestureLeft = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(swipeLeft:)];//need to set direction.
    [gestureLeft setDirection:(UISwipeGestureRecognizerDirectionLeft)];
    //[gesture setNumberOfTouchesRequired:1];//default is 1
    [[self view] addGestureRecognizer:gestureRight];//this gets things rolling.
    [[self view] addGestureRecognizer:gestureLeft];//this gets things rolling.
}

swipeRight和swipeLeft是您用于根据向左或向右滑动执行特定活动的方法。例如：

- (void)swipeRight:(UISwipeGestureRecognizer *)gesture
{
    NSLog(@"Right Swipe received.");//Lets you know this method was called by gesture recognizer.
    NSLog(@"Direction is: %i", gesture.direction);//Lets you know the numeric value of the gesture direction for confirmation (1=right).
    //only interested in gesture if gesture state == changed or ended (From Paul Hegarty @ standford U
    if ((gesture.state == UIGestureRecognizerStateChanged) ||
    (gesture.state == UIGestureRecognizerStateEnded)) {

    //do something for a right swipe gesture.
    }
}

Answer 8

UISwipeGestureRecognizer *Updown=[[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(handleGestureNext:)];
            Updown.delegate=self;
            [Updown setDirection:UISwipeGestureRecognizerDirectionDown | UISwipeGestureRecognizerDirectionUp];
            [overLayView addGestureRecognizer:Updown];

            UISwipeGestureRecognizer *LeftRight=[[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(handleGestureNext:)];
            LeftRight.delegate=self;
            [LeftRight setDirection:UISwipeGestureRecognizerDirectionLeft | UISwipeGestureRecognizerDirectionRight];
            [overLayView addGestureRecognizer:LeftRight];
            overLayView.userInteractionEnabled=NO;


    -(void)handleGestureNext:(UISwipeGestureRecognizer *)recognizer
    {
        NSLog(@"Swipe Recevied");
        //Left
        //Right
        //Top
        //Bottom
    }

Answer 9

Swift 2.1

我必须使用以下

    for var x in [
        UISwipeGestureRecognizerDirection.Left,
        UISwipeGestureRecognizerDirection.Right,
        UISwipeGestureRecognizerDirection.Up,
        UISwipeGestureRecognizerDirection.Down
    ] {
        let r = UISwipeGestureRecognizer(target: self, action: "swipe:")
        r.direction = x
        self.view.addGestureRecognizer(r)
    }

Answer 10

嗯，奇怪，它对我来说很完美，我做的完全一样

认为你应该试试看

UIGestureRecognizerDelegate方法

- (BOOL)gestureRecognizerShouldBegin:(UISwipeGestureRecognizer *)gestureRecognizer {
   // also try to look what's wrong with gesture
   NSLog(@"should began gesture %@", gestureRecognizer);
   return YES;
}

在日志中你必须看到类似的内容：

应该开始做手势; target =＆lt;（action = actionForUpDownSwipeGestureRecognizer：，target =）＆gt ;;方向=上，下，左，右＆gt;

Answer 11

使用它，它应该是位操作

   gesture.direction & UISwipeGestureRecognizerDirectionUp || 
   gesture.direction & UISwipeGestureRecognizerDirectionDown

Answer 12

这让我发疯了。我终于找到了一种可靠的方法来拥有多个swipeGestureRecognizer。

如果“action”选择器的名称在多个swipeGestureRecognizer中相同，则iOS中似乎存在错误。如果您只是以不同的名称命名，例如handleLeftSwipeFrom和handleRightSwipeFrom，一切正常。

UISwipeGestureRecognizer *recognizer;

recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleLeftSwipeFrom:)];
[recognizer setDirection:(UISwipeGestureRecognizerDirectionLeft)];
[[self view] addGestureRecognizer:recognizer];
[recognizer release];

recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleRightSwipeFrom:)];
[recognizer setDirection:(UISwipeGestureRecognizerDirectionRight)];
[[self view] addGestureRecognizer:recognizer];
[recognizer release];