GestureRecognizer not responding to tap - ios

Question

After initialisation of by subclass of UIImageView I have the following line of code:
self.userInteractionEnabled = true
self.addGestureRecognizer(UITapGestureRecognizer(target: self, action: "handleTap:"))
I created the necessary associated function :
func handleTap(gestureRecognizer: UITapGestureRecognizer) {
print("In handler")
}
On tapping on the view in question, "In handler was never printed to the console". I then removed the handler function to see if the compiler would complain about the missing function. It didn't.
I'm positively stumped. I'd truly appreciate any light people can shed on this.
Update: My class is actually a UIImageView as opposed to UIView

Answer 1

I was using UITapGestureRecognizer that I placed on a UILabel using Storyboard.
To get this to work I also had to place a checkmark in the block labeled: "User Interaction Enabled" in the UILabel Attributes Inspector in the Storyboard.

Answer 2

I discovered the answer after carefully combing through my code.
One of the parent views was created without supplying a frame:
While it's a noobish enough error to warrant deletion of this questions, odds are someone else will also have the same issue in the future...

Answer 3

Try this
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)
self.view.userInteractionEnabled = true
var tapGesture = UITapGestureRecognizer(target: self, action: Selector("handleTap:"))
self.view.addGestureRecognizer(tapGesture)
}
func handleTap(sender : UIView) {
println("Tap Gesture recognized")
}

Answer 4

In addition to the other answers, this can be caused by adding the gesture recognizer to multiple views. Gesture recognizers are for single views only.
Reference: https://stackoverflow.com/a/5567684/6543020

Answer 5

I ran into this problem with programmatic views.
My UIView with the gesture recognizer had .isUserInteractionEnabled = true, but it did not respond to taps until I set .isUserInteractionEnabled = true for its parent views as well.

Answer 6

Most likely you add UIGestureRecognizer in wrong place. Here is working sample with UIView from storyboard. If you create your UIView dynamically then you should put this initialization in the correct constructor.
class TestView: UIView
{
override func awakeFromNib()
{
self.userInteractionEnabled = true
self.addGestureRecognizer(UITapGestureRecognizer(target: self, action: "handleTap:"))
}
func handleTap(gestureRecognizer: UITapGestureRecognizer)
{
println("Here")
}
}

Answer 7

I found the solution to this problem after lot of trial and error. So there are two solution two this
1. Either add the GestureRecognizer in viewDidLoad() and turn
userInteractionEnabled = true
2. If using computed property use lazy var instead of let to the property.
lazy var profileImageView: UIImageView = {
let iv = UIImageView(frame: CGRect(x: 0, y: 0, width: 100, height: 100))
iv.image = #imageLiteral(resourceName: "gameofthrones_splash")
iv.contentMode = .scaleAspectFill
iv.translatesAutoresizingMaskIntoConstraints = false
iv.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(handleSelectProfileImageView)))
iv.isUserInteractionEnabled = true
return iv
}()

Answer 8

For anyone that is still having problems even with all the previous answers, make sure you are using UITapGestureRecognizer instead of UIGestureRecognizer, I kept missing this detail while trying to find what was wrong.

Answer 9

This Code works for me with XCode 7.0.1
import UIKit
class ImageView: UIImageView {
init(frame: CGRect, sender: Bool, myImage: UIImage) {
super.init(frame: frame)
self.image = myImage
initBorderStyle(sender)
// enable user interaction on image.
self.userInteractionEnabled = true
let gesture = UITapGestureRecognizer(target: self, action: "previewImage:")
addGestureRecognizer(gesture)
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
func previewImage(myGesture: UITapGestureRecognizer? = nil) {
print("i'm clicked")
}
private func initBorderStyle(sender: Bool) {
self.layer.masksToBounds = true
self.layer.cornerRadius = 8
self.layer.borderWidth = 0.5
self.layer.borderColor = getBorderColor(sender)
self.backgroundColor = getColor(sender)
}
func getBorderColor(sender: Bool) -> CGColor {
var result: CGColor
if sender {
result = UIColor(red: 0.374, green: 0.78125, blue: 0.0234375, alpha: 0.5).CGColor
} else {
result = UIColor(red: 0.3125, green: 0.6015625, blue: 0.828125, alpha: 0.5).CGColor
}
return result
}
}

Answer 10

Xcode 11.4 Swift 5.2
UserInteraction is enabled by default on Custom UIView
import UIKit
class YourView: UIView {
override init(frame: CGRect) {
super.init(frame: frame)
commonInit()
}
required init?(coder: NSCoder) {
super.init(coder: coder)
commonInit()
}
func commonInit() {
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(tapped))
self.addGestureRecognizer(tapGesture)
}
#objc func tapped() {
// do something
}
}
If you want to be notified elsewhere that the custom UIView has been tapped, then it is convenient to use a Notification.
It is best to create this as an extension to prevent it being Stringly typed.
extension Notification.Name {
static let DidTapMyView = Notification.Name("DidTapMyView")
}
In your custom UIView when the tapped function is called
#objc func tapped() {
NotificationCenter.default.post(name: .DidTapMyView, object: self)
}
In your UIViewController where you want to listen for the Notification:
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(myViewWasTapped), name: .DidTapMyView, object: nil)
}
#objc func myViewWasTapped() {
// Notified here - do something
}

Answer 11

Here's a list of my findings in 2021, XCode 13:
Make sure both your view and all of its superviews have set width & height constraints(this one is crucial)
Set isUserInteractionEnabled = true for your view
There's no need to set explicit frame or isUserInteractionEnabled for other super views

Answer 12

In addition the above (userInteractionEnabled, clipsToBounds, etc.), if you are working with a view in a child view controller be sure that you have added it as a child with myParentViewController.addChild(myChildViewController) — we've run into a couple of situations now where visible views were not firing recognizing gestures because their view controllers hadn't been added, and presumably the VCs themselves were not being retained.

Answer 13

It turned out that my gesture didn't work because it was in a normal class, and not a subclass of UIView or anything.
I solved the issue by creating a subclass of UIView that I had an instance of in this normal class and placed the gesture logic in that.

Answer 14

I solved my issue by setting the height to the UIView.
optionView.heightAnchor.constraint(equalToConstant: 18).isActive = true

Answer 15

I had the same issue in my programmatically created ViewController. The bug was fixed when I added a backgroundColor to the view.
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .systemBackground
let tap = UITapGestureRecognizer(target: self.view, action: #selector(UIView.endEditing))
view.addGestureRecognizer(tap)
}
}