addTarget and addGestureRecognizer not working, no crash/error - ios

Question

I a have an overlay with a table in and I'd like to add a Tap gesture recogniser to the background to dismiss the view and also addTarget to a button within the overlay which does the same thing.
The overlay displays fine as expected, however whenever I tap the black background or the cancel button, nothing happens. I've searched for an answer here but nothing found has worked. My code is as follows, followed by a screenshot of the overlay:
class importedFileView: NSObject {
let blackView = UIView()
let importedFileContainerView: UIView = {
let importedFileContainerView = UIView(frame: .zero)
importedFileContainerView.backgroundColor = .white
importedFileContainerView.layer.cornerRadius = 10
importedFileContainerView.layer.masksToBounds = true
return importedFileContainerView
}()
let headerLabel: UILabel = {
let headerLabel = UILabel()
headerLabel.translatesAutoresizingMaskIntoConstraints = false
headerLabel.font = UIFont(name: "HelveticaNeue-Thin" , size: 24)
headerLabel.text = "Attach file"
headerLabel.textColor = .darkGray
headerLabel.adjustsFontSizeToFitWidth = true
return headerLabel
}()
let fileTableView: UITableView = {
let fileTableView = UITableView()
return fileTableView
}()
let updateDetailsButton: UIButton = {
let updateDetailsButton = UIButton()
updateDetailsButton.translatesAutoresizingMaskIntoConstraints = false
updateDetailsButton.backgroundColor = UIColor(r:40, g:86, b:131)
updateDetailsButton.setTitleColor(UIColor.white, for: .normal)
updateDetailsButton.setTitle("Attach selected files", for: .normal)
updateDetailsButton.titleLabel!.font = UIFont(name: "HelveticaNeue-Light" , size: 18)
updateDetailsButton.layer.cornerRadius = 2
return updateDetailsButton
}()
let cancelButton: UIButton = {
let cancelButton = UIButton()
cancelButton.translatesAutoresizingMaskIntoConstraints = false
cancelButton.backgroundColor = UIColor.white
cancelButton.setTitleColor(UIColor(r:40, g:86, b:131), for: .normal)
cancelButton.setTitle("Cancel", for: .normal)
cancelButton.titleLabel!.font = UIFont(name: "HelveticaNeue-Light" , size: 18)
cancelButton.layer.cornerRadius = 2
return cancelButton
}()
let frameHeight: CGFloat = 450
func showFormView(){
if let window = UIApplication.shared.keyWindow {
blackView.backgroundColor = UIColor(white: 0, alpha: 0.5)
window.addSubview(blackView)
window.addSubview(importedFileContainerView)
importedFileContainerView.addSubview(headerLabel)
importedFileContainerView.addSubview(fileTableView)
importedFileContainerView.addSubview(updateDetailsButton)
importedFileContainerView.addSubview(cancelButton)
cancelButton.addTarget(self, action: #selector(handleDismiss), for: .touchUpInside)
blackView.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(handleDismiss)))
layoutViews()
fileTableView.frame = CGRect(x: 30, y: window.frame.height, width: window.frame.width - 60, height: 230)
let frameY = (window.frame.height - frameHeight) / 2
importedFileContainerView.frame = CGRect(x: 20, y: window.frame.height, width: window.frame.width - 40, height: self.frameHeight)
blackView.frame = window.frame
blackView.alpha = 0
UIView.animate(withDuration: 0.5, delay: 0, usingSpringWithDamping: 1, initialSpringVelocity: 1, options: .curveEaseOut, animations: {
self.blackView.alpha = 1
self.importedFileContainerView.frame = CGRect(x: 20, y: frameY, width: window.frame.width - 40, height: self.frameHeight)
}, completion: nil
)
}
}
func layoutViews(){
let views = ["v0" : headerLabel, "v1": fileTableView, "v2": updateDetailsButton, "v3": cancelButton]
let leftSpace = NSLayoutConstraint.constraints(withVisualFormat: "H:|-20.0-[v0]-20.0-|", options: NSLayoutFormatOptions(), metrics: nil, views: views)
let leftSpace1 = NSLayoutConstraint.constraints(withVisualFormat: "H:|-20.0-[v1]-20.0-|", options: NSLayoutFormatOptions(), metrics: nil, views: views)
let leftSpace2 = NSLayoutConstraint.constraints(withVisualFormat: "H:|-20.0-[v2]-20.0-|", options: NSLayoutFormatOptions(), metrics: nil, views: views)
let leftSpace3 = NSLayoutConstraint.constraints(withVisualFormat: "H:|-20.0-[v3]-20.0-|", options: NSLayoutFormatOptions(), metrics: nil, views: views)
let topSpacing = NSLayoutConstraint.constraints(withVisualFormat: "V:|-20.0-[v0(40)]-20.0-[v1(230)]-20.0-[v2(50)]-10.0-[v3(50)]-10.0-|", options: NSLayoutFormatOptions(), metrics: nil, views: views)
importedFileContainerView.addConstraints(topSpacing)
importedFileContainerView.addConstraints(leftSpace)
importedFileContainerView.addConstraints(leftSpace1)
importedFileContainerView.addConstraints(leftSpace2)
importedFileContainerView.addConstraints(leftSpace3)
}
func handleDismiss() {
UIView.animate(withDuration: 0.5,
delay: 0.0,
options: .curveEaseInOut,
animations: {
self.blackView.alpha = 0
if let window = UIApplication.shared.keyWindow {
self.importedFileContainerView.frame = CGRect(x: 20, y: window.frame.height, width: window.frame.width - 40, height: self.frameHeight)
}
},
completion: { [weak self] finished in
self?.blackView.removeFromSuperview()
self?.importedFileContainerView.removeFromSuperview()
})
}
override init() {
super.init()
}
}

Answer 1

self.blackView.isUserInteractionEnabled = true;
is all you need to add to the blackView (UIView).
Without that, the view doesn't have any interactions enabled and so the gesture recognizer's target/action isn't triggered.
Events are ignored.
https://developer.apple.com/reference/uikit/uiview/1622577-isuserinteractionenabled
You might also want to disable it during animations.

Answer 2

Are you keeping a strong reference to the instance of your importedFileView while your overlays are visible? As far as I tested, all actions are silently ignored when the target is lost.
For example, this does not work:
#IBAction func someAction(_ sender: Any) {
let ifv = importedFileView()
ifv.showFormView()
//`ifv` is released at the end of this method, then your overlays are shown...
}
This works:
let ifv = importedFileView() //keep the instance as a property of your ViewController.
#IBAction func someAction(_ sender: Any) {
ifv.showFormView()
}
Programmatically generated UIViews isUserInteractionEnabled is default to true. You have no need to explicitly set it to true.
By the way, you'd better not name your non-UIView class as ...View, and better make your type names start with capital letter, which makes your code more readable to experienced Swift programmers.