How to accelerate the identification of a single tap over a double tap?

Full Implementation of Markus's Swift 3 version of eladleb's original solution.

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Create subclass file UIShortTapGestureRecogninzer

import UIKit
import UIKit.UIGestureRecognizerSubclass 

class UIShortTapGestureRecognizer: UITapGestureRecognizer {
    let tapMaxDelay: Double = 0.3 //anything below 0.3 may cause doubleTap to be inaccessible by many users

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {
        super.touchesBegan(touches, with: event)

        DispatchQueue.main.asyncAfter(deadline: .now() + tapMaxDelay) { [weak self] in
            if self?.state != UIGestureRecognizerState.recognized {
                self?.state = UIGestureRecognizerState.failed
            }
        }
    }
}

Note: When adding UIGestureRecognizer only doubleTap needs to be of type UIShortTapGestureRecognizer & singleTap.require(toFail: doubleTap) is required.

func addBoth (views: UIView, selectorSingle: Selector, selectorDouble: Selector) {
    let doubleTap:UIShortTapGestureRecognizer = UIShortTapGestureRecognizer(target: self, action: selectorDouble)
    doubleTap.numberOfTapsRequired = 2
    views.addGestureRecognizer(doubleTap)

    let singleTap:UITapGestureRecognizer = UITapGestureRecognizer(target: self, action: selectorSingle)
    singleTap.numberOfTapsRequired = 1
    singleTap.require(toFail: doubleTap)
    views.addGestureRecognizer(singleTap)
}

I found the answer on this link

The swift version:

class UIShortTapGestureRecognizer: UITapGestureRecognizer {
    let tapMaxDelay: Double = 0.3

    override func touchesBegan(touches: NSSet!, withEvent event: UIEvent!) {
        super.touchesBegan(touches, withEvent: event)
        delay(tapMaxDelay) {
            // Enough time has passed and the gesture was not recognized -> It has failed.
            if  self.state != UIGestureRecognizerState.Ended {
                self.state = UIGestureRecognizerState.Failed
            }
        }
    }
}

With delay(delay: Double, closure:()->()):

class func delay(delay:Double, closure:()->()) {
        dispatch_after(dispatch_time( DISPATCH_TIME_NOW, Int64(delay * Double(NSEC_PER_SEC))), dispatch_get_main_queue(), closure)
    }