How to have a UISwipeGestureRecognizer AND UIPanGestureRecognizer work on the same view

Question

How would you setup the gesture recognizers so that you could have a UISwipeGestureRecognizer and a UIPanGestureRecognizer work at the same

Answer 1

Here is a full solution for detecting pan and swipe directions (utilizing 2cupsOfTech's swipeThreshold logic):

public enum PanSwipeDirection: Int {
    case up, down, left, right, upSwipe, downSwipe, leftSwipe, rightSwipe
    public var isSwipe: Bool { return [.upSwipe, .downSwipe, .leftSwipe, .rightSwipe].contains(self) }
    public var isVertical: Bool { return [.up, .down, .upSwipe, .downSwipe].contains(self) }
    public var isHorizontal: Bool { return !isVertical }
}

public extension UIPanGestureRecognizer {

   var direction: PanSwipeDirection? {
        let SwipeThreshold: CGFloat = 1000
        let velocity = self.velocity(in: view)
        let isVertical = abs(velocity.y) > abs(velocity.x)
        switch (isVertical, velocity.x, velocity.y) {
        case (true, _, let y) where y < 0: return y < -SwipeThreshold ? .upSwipe : .up
        case (true, _, let y) where y > 0: return y > SwipeThreshold ? .downSwipe : .down
        case (false, let x, _) where x > 0: return x > SwipeThreshold ? .rightSwipe : .right
        case (false, let x, _) where x < 0: return x < -SwipeThreshold ? .leftSwipe : .left
        default: return nil
        }
    }

}

Usage:

@IBAction func handlePanOrSwipe(recognizer: UIPanGestureRecognizer) {

    if let direction = recognizer.direction {
        if direction == .leftSwipe {
            //swiped left
        } else if direction == .up {
            //panned up
        } else if direction.isVertical && direction.isSwipe {
            //swiped vertically
        }
    }

}

Answer 2

Using a pan recognizer to detect swipping and panning:

- (void)setupRecognizer
{
    UIPanGestureRecognizer* panSwipeRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePanSwipe:)];
    // Here you can customize for example the minimum and maximum number of fingers required
    panSwipeRecognizer.minimumNumberOfTouches = 2;
    [targetView addGestureRecognizer:panSwipeRecognizer];
}

#define SWIPE_UP_THRESHOLD -1000.0f
#define SWIPE_DOWN_THRESHOLD 1000.0f
#define SWIPE_LEFT_THRESHOLD -1000.0f
#define SWIPE_RIGHT_THRESHOLD 1000.0f

- (void)handlePanSwipe:(UIPanGestureRecognizer*)recognizer
{
    // Get the translation in the view
    CGPoint t = [recognizer translationInView:recognizer.view];
    [recognizer setTranslation:CGPointZero inView:recognizer.view];

    // TODO: Here, you should translate your target view using this translation
    someView.center = CGPointMake(someView.center.x + t.x, someView.center.y + t.y);

    // But also, detect the swipe gesture
    if (recognizer.state == UIGestureRecognizerStateEnded)
    {
        CGPoint vel = [recognizer velocityInView:recognizer.view];

        if (vel.x < SWIPE_LEFT_THRESHOLD)
        {
            // TODO: Detected a swipe to the left
        }
        else if (vel.x > SWIPE_RIGHT_THRESHOLD)
        {
            // TODO: Detected a swipe to the right
        }
        else if (vel.y < SWIPE_UP_THRESHOLD)
        {
            // TODO: Detected a swipe up
        }
        else if (vel.y > SWIPE_DOWN_THRESHOLD)
        {
            // TODO: Detected a swipe down
        }
        else
        {
            // TODO:
            // Here, the user lifted the finger/fingers but didn't swipe.
            // If you need you can implement a snapping behaviour, where based on the location of your         targetView,
            // you focus back on the targetView or on some next view.
            // It's your call
        }
    }
}

Answer 3

You're going to want to set one of the two UIGestureRecognizer's delegates to an object that makes sense (likely self) then listen, and return YES for this method:

- (BOOL) gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer
         shouldRecognizeSimultaneouslyWithGestureRecognizer:
                            (UIGestureRecognizer *)otherGestureRecognizer {
    return YES;
}

This method is called when recognition of a gesture by either gestureRecognizer or otherGestureRecognizer would block the other gesture recognizer from recognizing its gesture. Note that returning YES is guaranteed to allow simultaneous recognition; returning NO, on the other hand, is not guaranteed to prevent simultaneous recognition because the other gesture recognizer's delegate may return YES.

Answer 4

By default, when the user attempts to swipe, the gesture is interpreted as a pan. This is because a swiping gesture meets the necessary conditions to be interpreted as a pan (a continuous gesture) before it meets the necessary conditions to be interpreted as a swipe (a discrete gesture).

You need to indicate a relationship between two gesture recognizers by calling the requireGestureRecognizerToFail: method on the gesture recognizer that you want to delay

[self.panRecognizer requireGestureRecognizerToFail:self.swipeRecognizer];