Simultaneous Gesture Recognition for Specific Gestures

Simultaneous gesture recognition for specific gestures

Make sure your class implements UIGestureRecognizerDelegate

class YourViewController: UIViewController, UIGestureRecognizerDelegate ...

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Set the gesture's delegate to self

yourGesture.delegate = self

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Add delegate function to your class

func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool {
    if (gestureRecognizer is UIPanGestureRecognizer || gestureRecognizer is UIRotationGestureRecognizer) {
        return true
    } else {
        return false
    }
}

Simultaneous gesture recognizers in Iphone SDK

It was really easy:

At first we should create class, that implements UIGestureRecognizerDelegate protocol:

@interface MyGestureDelegate : NSObject <UIGestureRecognizerDelegate>

@implementation MyGestureDelegate

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

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

And use it like this:

    UISwipeGestureRecognizer *swipeGestureLeft = [[UISwipeGestureRecognizer alloc]
                                              initWithTarget:self action:@selector(handleSwipeGestureLeft:)];
    [self.view addGestureRecognizer:swipeGestureLeft];
    swipeGestureLeft.direction = UISwipeGestureRecognizerDirectionLeft;
    [swipeGestureLeft release];

    UISwipeGestureRecognizer *swipeGesture = [[UISwipeGestureRecognizer alloc]
                                          initWithTarget:self action:@selector(handleSwipeGesture:)];
    swipeGesture.direction = UISwipeGestureRecognizerDirectionRight;
    [self.view addGestureRecognizer:swipeGesture];

    MyGestureDelegate *deleg = [[MyGestureDelegate alloc] init];

    [swipeGesture setDelegate:deleg];
    [swipeGesture release];

Handling Multiple GestureRecognizers

The UIGestureRecognizerDelegate has a special function managing simultaneous recognition of several gestures on the same object, that will do the trick.

1) Set your UIViewController to conform UIGestureRecognizerDelegate

2) Implement the following function:

func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool {

    if (gestureRecognizer == mainScene.panRecognizer || gestureRecognizer == mainScene.pinchRecognizer) && otherGestureRecognizer == mainScene.tapRecognizer {
        return true
    }
    return false
}

In this particular example we allow the tap gesture to get triggered simultaneously with panning and pinching.

3) Then just assign the delegates to the pan and pinch gesture recognizers:

override func viewDidLoad() {
    // your code...

    // Set gesture recognizers delegates
    mainScene.panRecognizer.delegate = self
    mainScene.pinchRecognizer.delegate = self
}

How to detect the end of simultaneous gestures? (iOS)

How about a simple solution like counting gestures that are currently being handled, and acting when all of them end?

.h file:

int handledGesturesCount;

.m file:

- (id)init {
    (...)
    handledGesturesCount = 0;
}

// gesture handlers - the code for -pinch: repeats for -pan: and -rotate:
- (void)pinch:(UIPinchGestureRecognizer *)recognizer {
    if (recognizer.state == UIGestureRecognizerStateBegan) {
        handledGesturesCount += 1;
    } else if (recognizer.state == UIGestureRecognizerStateEnded ||
               recognizer.state == UIGestureRecognizerStateCancelled ||
               recognizer.state == UIGestureRecognizerStateFailed)
    {
        handledGesturesCount -= 1;
        if (handledGesturesCount == 0) {
            [self resetImage];
        }
    }
}

- (void)pan:(UIPanGestureRecognizer *)recognizer {
    if (recognizer.state == UIGestureRecognizerStateBegan) {
        handledGesturesCount += 1;
    } else if (recognizer.state == UIGestureRecognizerStateEnded ||
               recognizer.state == UIGestureRecognizerStateCancelled ||
               recognizer.state == UIGestureRecognizerStateFailed)
    {
        handledGesturesCount -= 1;
        if (handledGesturesCount == 0) {
            [self resetImage];
        }
    }
}

- (void)rotate:(UIRotationGestureRecognizer *)recognizer {
    if (recognizer.state == UIGestureRecognizerStateBegan) {
        handledGesturesCount += 1;
    } else if (recognizer.state == UIGestureRecognizerStateEnded ||
               recognizer.state == UIGestureRecognizerStateCancelled ||
               recognizer.state == UIGestureRecognizerStateFailed)
    {
        handledGesturesCount -= 1;
        if (handledGesturesCount == 0) {
            [self resetImage];
        }
    }
}

iOS: recognize pinch gestures but not two finger pans?

Have you try like this

func gestureRecognizer(gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWithGestureRecognizer otherGestureRecognizer: UIGestureRecognizer) -> Bool {
    if ((gestureRecognizer is UIPinchGestureRecognizer || gestureRecognizer is UIPanGestureRecognizer)
         && (otherGestureRecognizer is UIPinchGestureRecognizer || otherGestureRecognizer is UIPanGestureRecognizer))  {
        return false
    }
    return true
}

How to recognise gestures on pop-up view without interrupting gesture recognition on the view underneath?

After two days' work I found a very simple answer. I hope it helps someone. In the initialisation of the pop-up view, simply add the gesture recogniser to the superview, or any full-screen view, rather than the pop-up's own view. The target can still be the pop-up view:

    self.recognizer = [[MyGestureRecognizer alloc] initWithTarget:self action:@selector(tapped:)];
    [fullscreenView addGestureRecognizer:self.recognizer];

And then disable user interaction:

    self.userInteractionEnabled = NO;

This doesn't affect the gesture on the pop-up view, and the gestures associated with views underneath the pop-up now work fine too. If they compete with each other then the overrides in lorenzoliveto's answer can sort that.

ios recognizing gestures simultaneously with object handling

If you set your view controller to be the delegate of your gestures, you can implement:

- (BOOL) gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer

I'm not sure if you're also trying to have the view handle touch events separately, but if you are, I'd recommend subclassing UIGestureRecognizer and handle touch events there.

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