Adding UIGestureRecognizer To Subview Programmatically in Swift

Question

I currently have a subview that is created and added to the UIView in ViewDidLoad(). I am attempting to user UIGestureRecognizers to detect a tap and unhide a particular button. My current code:

 override func viewDidLoad() {
    super.viewDidLoad()
    architectView = CustomClass(frame: self.view.bounds)
    self.view.addSubview(architectView)        
    let gestureRecognizer = UITapGestureRecognizer(target: self, action: "handleTap:")
    gestureRecognizer.delegate = self
    architectView.addGestureRecognizer(gestureRecognizer)
}

func handleTap(gestureRecognizer: UIGestureRecognizer) {
    let alert = UIAlertController(title: "Alert", message: "Message", preferredStyle: UIAlertControllerStyle.Alert)
    alert.addAction(UIAlertAction(title: "Click", style: UIAlertActionStyle.Default, handler: nil))
    self.presentViewController(alert, animated: true, completion: nil)
}

The handleTap() function is a simple test to see if the taps are being recognized. This code does not trigger the UIAlert when it is pressed? What am I missing?

Have you tried putting a break point in handleTap: to see if the function is even getting called? — John Riselvato, Feb 17 '16 at 20:28
I have just tested. I create an outlet for the main UIView and added the UIGestureRecognizer to the view. The function handleTap() does not get called — Andrew Walz, Feb 17 '16 at 20:38

score 13 · Accepted Answer · answered Feb 17 '16 at 21:06

I tested your code here and it does work. However, I think you might be missing to add the UIGestureRecognizerDelegate protocol to your View Controller. See below:

class ViewController: UIViewController, UIGestureRecognizerDelegate {

    var architectView = UIView()

    override func viewDidLoad() {
        super.viewDidLoad()
        architectView = UIView(frame: self.view.bounds)
        self.view.addSubview(architectView)
        let gestureRecognizer = UITapGestureRecognizer(target: self, action: "handleTap:")
        gestureRecognizer.delegate = self
        architectView.addGestureRecognizer(gestureRecognizer)
    }

    func handleTap(gestureRecognizer: UIGestureRecognizer) {
        let alert = UIAlertController(title: "Alert", message: "Message", preferredStyle: UIAlertControllerStyle.Alert)
        alert.addAction(UIAlertAction(title: "Click", style: UIAlertActionStyle.Default, handler: nil))
        self.presentViewController(alert, animated: true, completion: nil)
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

}

score 10 · Answer 2 · answered Mar 13 '17 at 21:00

Swift 3 version code based on Raphael Silva answer:

import UIKit

class ViewController: UIViewController, UIGestureRecognizerDelegate {

    var architectView = UIView()

    override func viewDidLoad() {
        super.viewDidLoad()
        architectView = UIView(frame: self.view.bounds)
        self.view.addSubview(architectView)
        let gestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(ViewController.handleTap(gestureRecognizer:)))
        gestureRecognizer.delegate = self
        architectView.addGestureRecognizer(gestureRecognizer)
    }

    func handleTap(gestureRecognizer: UIGestureRecognizer) {
        let alert = UIAlertController(title: "Alert", message: "Message", preferredStyle: UIAlertControllerStyle.alert)
        alert.addAction(UIAlertAction(title: "Click", style: UIAlertActionStyle.default, handler: nil))
        self.present(alert, animated: true, completion: nil)
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

}

Oh my goodness. Thank you, I've bee searching far and wide for the only MODERN answer that works. Why in the world does Apple deprecate so much. Most of their deprecations seem completely unnecessary and just cause confusion smh. — Ben Akin, Mar 08 '18 at 23:45

Adding UIGestureRecognizer To Subview Programmatically in Swift

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