26

我需要识别所有方向的滑动（上/下/左/右）。不是同时，但我需要认出它们。

我试过了：

  UISwipeGestureRecognizer *Swipe = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(SwipeRecognizer:)];
  Swipe.direction = (UISwipeGestureRecognizerDirectionLeft | 
                     UISwipeGestureRecognizerDirectionRight |
                     UISwipeGestureRecognizerDirectionDown | 
                     UISwipeGestureRecognizerDirectionUp);
  [self.view addGestureRecognizer:Swipe];
  [Swipe release];

但什么都没有出现SwipeRecognizer

这是 SwipeRecognizer 的代码：

- (void) SwipeRecognizer:(UISwipeGestureRecognizer *)sender {
  if ( sender.direction == UISwipeGestureRecognizerDirectionLeft )
    NSLog(@" *** SWIPE LEFT ***");
  if ( sender.direction == UISwipeGestureRecognizerDirectionRight )
    NSLog(@" *** SWIPE RIGHT ***");
  if ( sender.direction == UISwipeGestureRecognizerDirectionDown )
    NSLog(@" *** SWIPE DOWN ***");
  if ( sender.direction == UISwipeGestureRecognizerDirectionUp )
    NSLog(@" *** SWIPE UP ***");
}

我怎样才能做到这一点？如何将所有不同的方向分配给我的 Swipe 对象？

4

8 回答 8

21

你这样设置方向

  UISwipeGestureRecognizer *Swipe = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(SwipeRecognizer:)];
  Swipe.direction = (UISwipeGestureRecognizerDirectionLeft | 
                     UISwipeGestureRecognizerDirectionRight |
                     UISwipeGestureRecognizerDirectionDown | 
                     UISwipeGestureRecognizerDirectionUp);

这就是你收到回调时的方向，所以你所有的测试都失败是正常的。如果你有

- (void) SwipeRecognizer:(UISwipeGestureRecognizer *)sender {
  if ( sender.direction | UISwipeGestureRecognizerDirectionLeft )
    NSLog(@" *** SWIPE LEFT ***");
  if ( sender.direction | UISwipeGestureRecognizerDirectionRight )
    NSLog(@" *** SWIPE RIGHT ***");
  if ( sender.direction | UISwipeGestureRecognizerDirectionDown )
    NSLog(@" *** SWIPE DOWN ***");
  if ( sender.direction | UISwipeGestureRecognizerDirectionUp )
    NSLog(@" *** SWIPE UP ***");
}

测试会成功（但所有测试都会成功，因此您不会从中获得任何信息）。如果您想区分不同方向的滑动，您将需要单独的手势识别器。

编辑

正如评论中所指出的，请参阅此答案。显然，即使这样也行不通。您应该创建只有一个方向的滑动，以使您的生活更轻松。

于 2011-11-18T11:46:19.993 回答
4

不幸的是，您不能使用direction属性来监听识别器；它只为您提供识别器检测到的方向。UISwipeGestureRecognizer为此，我使用了两个不同的 s，请在此处查看我的答案： https ://stackoverflow.com/a/16810160/936957

于 2013-05-29T09:27:43.837 回答
4

我之前实际上遇到过这个确切的问题。我最终做的是创建一个 UIView 子类，覆盖touchesMoved:并做一些数学来计算方向。

这是一般的想法：

#import "OmnidirectionalControl.h"

typedef NS_ENUM(NSInteger, direction) {
    Down = 0, DownRight = 1,
    Right = 2, UpRight = 3,
    Up = 4, UpLeft = 5,
    Left = 6, DownLeft = 7
};

@interface OmnidirectionalControl ()

@property (nonatomic) CGPoint startTouch;
@property (nonatomic) CGPoint endTouch;

@end

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    self.startTouch = [[touches allObjects][0] locationInView:self];
}

-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
    self.lastTouch = [[[touches allObjects] lastObject] locationInView:self];
    NSLog(@"Direction: %d", [self calculateDirectionFromTouches]);
}

-(direction)calculateDirectionFromTouches {
    NSInteger xDisplacement = self.lastTouch.x-self.startTouch.x;
    NSInteger yDisplacement = self.lastTouch.y-self.startTouch.y;

    float angle = atan2(xDisplacement, yDisplacement);
    int octant = (int)(round(8 * angle / (2 * M_PI) + 8)) % 8;

    return (direction) octant;
}

为简单起见touchesMoved:，我只记录方向，但您可以使用该信息做您想做的事情（例如将其传递给代表、发布通知等）。touchesMoved你还需要一些方法来识别滑动是否完成，但这与问题不太相关，所以我将把它留给你。这里calculateDirectionFromTouches解释了数学。

于 2013-11-13T06:29:26.200 回答
2

我终于找到了最简单的答案，如果您同意，请将其标记为答案。

如果您只有一个方向滑动 + 平移，您只需说：[myPanRecogznier requireGestureRecognizerToFail:mySwipeRecognizer];

但是，如果您有两次或多次滑动，则不能将数组传递给该方法。为此，您需要实现 UIGestureRecognizerDelegate。

例如，如果您想识别 2 次滑动（左右滑动）并且还希望允许用户向上平移，则将手势识别器定义为属性或实例变量，然后将 VC 设置为平移上的委托手势识别器：

_swipeLeft = [[UISwipeGestureRecognizer alloc] ...]; // use proper init here
_swipeRight = [[UISwipeGestureRecognizer alloc] ...]; // user proper init here
_swipeLeft.direction = UISwipeGestureRecognizerDirectionLeft;
_swipeRight.direction = UISwipeGestureRecognizerDirectionRight;
_pan = [[UIPanGestureRecognizer alloc] ...]; // use proper init here

_pan.delegate = self;

// then add recognizers to your view

然后实现 - (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRequireFailureOfGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer 委托方法，如下所示：

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRequireFailureOfGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
    if (gestureRecognizer == _pan && (otherGestureRecognizer == _swipeLeft || otherGestureRecognizer == _swipeRight)) {
        return YES;
    }

    return NO;
}

这告诉平移手势识别器仅在左右滑动都无法识别时才起作用 - 完美！

希望在未来，Apple 会让我们将一个数组传递给 requireGestureRecognizerToFail: 方法。

于 2013-12-22T21:41:11.797 回答
1

您可以通过 SwipeGesture 仅添加一条对角线，然后...

    UISwipeGestureRecognizer *swipeV = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(action)];
    UISwipeGestureRecognizer *swipeH = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(action)];
    swipeH.direction = ( UISwipeGestureRecognizerDirectionLeft | UISwipeGestureRecognizerDirectionRight  );
    swipeV.direction = ( UISwipeGestureRecognizerDirectionUp | UISwipeGestureRecognizerDirectionDown );
    [self addGestureRecognizer:swipeH];
    [self addGestureRecognizer:swipeV];
     self.userInteractionEnabled = YES;
于 2014-06-04T23:13:52.740 回答
1

使用 UIPanGestureRecogizer 并检测您关心的滑动方向。有关详细信息，请参阅 UIPanGestureRecognizer 文档。-rrh

// add pan recognizer to the view when initialized
UIPanGestureRecognizer *panRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(panRecognized:)];
[panRecognizer setDelegate:self];
[self addGestureRecognizer:panRecognizer]; // add to the view you want to detect swipe on


-(void)panRecognized:(UIPanGestureRecognizer *)sender
{
    if (sender.state == UIGestureRecognizerStateBegan) {
        // you might want to do something at the start of the pan
    }

    CGPoint distance = [sender translationInView:self]; // get distance of pan/swipe in the view in which the gesture recognizer was added
    CGPoint velocity = [sender velocityInView:self]; // get velocity of pan/swipe in the view in which the gesture recognizer was added
    float usersSwipeSpeed = abs(velocity.x); // use this if you need to move an object at a speed that matches the users swipe speed
    NSLog(@"swipe speed:%f", usersSwipeSpeed);
    if (sender.state == UIGestureRecognizerStateEnded) {
        [sender cancelsTouchesInView]; // you may or may not need this - check documentation if unsure
        if (distance.x > 0) { // right
            NSLog(@"user swiped right");
        } else if (distance.x < 0) { //left
            NSLog(@"user swiped left");
        }
        if (distance.y > 0) { // down
            NSLog(@"user swiped down");
        } else if (distance.y < 0) { //up
            NSLog(@"user swiped up");
        }
        // Note: if you don't want both axis directions to be triggered (i.e. up and right) you can add a tolerence instead of checking the distance against 0 you could check for greater and less than 50 or 100, etc.
    }
}

状态码中的浐灞

//如果您只想从向上、向下、向左和向右滑动一次

if (sender.state == UIGestureRecognizerStateEnded) {
        [sender cancelsTouchesInView]; // you may or may not need this - check documentation if unsure
        if (distance.x > 0 && abs(distance.x)>abs(distance.y)) { // right
            NSLog(@"user swiped right");
        } else if (distance.x < 0 && abs(distance.x)>abs(distance.y)) { //left
            NSLog(@"user swiped left");
        }
        if (distance.y > 0 && abs(distance.y)>abs(distance.x)) { // down
            NSLog(@"user swiped down");
        } else if (distance.y < 0 && abs(distance.y)>abs(distance.x)) { //up
            NSLog(@"user swiped up");
        }

    }
于 2013-01-28T18:11:11.380 回答
0 
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");
}
于 2014-09-22T12:00:19.057 回答
0

它可能不是最好的解决方案，但您始终可以为要检测的每个滑动方向指定不同的 UISwipeGestureRecognizer。

在 viewDidLoad 方法中只需定义所需的 UISwipeGestureRecognizer：

- (void)viewDidLoad{
    UISwipeGestureRecognizer *recognizerUp = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleSwipeUp:)];
    recognizerUp.direction = UISwipeGestureRecognizerDirectionUp;
    [[self view] addGestureRecognizer:recognizerUp];

    UISwipeGestureRecognizer *recognizerDown = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleSwipeDown:)];
    recognizerDown.direction =  UISwipeGestureRecognizerDirectionDown;
    [[self view] addGestureRecognizer:recognizerDown];
}

然后只需实现相应的方法来处理滑动：

- (void)handleSwipeUp:(UISwipeGestureRecognizer *)sender{
    if (sender.state == UIGestureRecognizerStateEnded){
        NSLog(@"SWIPE UP");
    }
}


- (void)handleSwipeDown:(UISwipeGestureRecognizer *)sender{
    if (sender.state == UIGestureRecognizerStateEnded){
        NSLog(@"SWIPE DOWN");
    }
}
于 2015-06-13T19:45:21.330 回答