TapGestureRecogniser not getting called when a subview - ios

Question

I have a view A that handles UITapGestureRecogniser. When it's on its own everything works great.
I have another View B that holds six of the View A objects. When I add View B to my ViewController the UITapGestureRecogniser stops working.
I have isUserInteractionEnabled = true on all the views.
Can anyone spot why it's not working?
How can I check if the tapGestures are being activated upon touch?
Thanks
Note: The ViewController doesn't have any UIGestureRecognisers on it
SingleView
class QTSingleSelectionView: UIView {
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
initialize()
}
override init(frame: CGRect) {
super.init(frame: frame)
initialize()
}
fileprivate func initialize() {
let tap = UITapGestureRecognizer(target: self, action: #selector(onTapListener))
addGestureRecognizer(tap)
}
func onTapListener() {
print("tap")
_isSelected.toggle()
setSelection(isSelected: _isSelected, animated: true)
}
}
Multiple views
class QTMutipleChoiceQuestionSelector: UIView {
var selectors: [QTSingleSelectionView] = []
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
initialize()
}
override init(frame: CGRect) {
super.init(frame: frame)
initialize()
}
fileprivate func initialize() {
for selector in selectors {
selector.removeFromSuperview()
}
selectors.removeAll()
guard let dataSource = dataSource else { return }
let count = dataSource.numberOfAnswers(self)
for index in 0..<count {
let selector = QTSingleSelectionView()
selector.frame = CGRect(x: 0, y: topMargin + heightOfSelector*CGFloat(index), width: frame.width, height: heightOfSelector)
selector.text = dataSource.mutipleChoiceQuestionSelector(self, textForAnswerAtIndex: index)
selector.selected = dataSource.mutipleChoiceQuestionSelector(self, isItemSelectedAtIndex: index)
selector.isUserInteractionEnabled = true
addSubview(selector)
}
}
}
ViewController
lazy var multipleChoiceView: QTMutipleChoiceQuestionSelector = {
let selector = QTMutipleChoiceQuestionSelector()
selector.dataSource = self
selector.isUserInteractionEnabled = true
return selector
}()
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
view.addSubview(multipleChoiceView)
}

Answer 1

I have tested your code. The problem is in line:
let selector = QTMutipleChoiceQuestionSelector() //Wrong!
This line initializes the view with frame (0,0,0,0), that means it cannot receive any touch event, even if you could see it.
The solution is giving the view a size to receive events:
let selector = QTMutipleChoiceQuestionSelector(frame: CGRect(x: 0.0, y: 0.0, width: self.view.frame.width, height: self.view.frame.height))

Answer 2

Try This -
Instead of :
for index in 0..<count {
let selector = QTSingleSelectionView()
selector.frame = CGRect(x: 0, y: topMargin + heightOfSelector*CGFloat(index), width: frame.width, height: heightOfSelector)
selector.text = dataSource.mutipleChoiceQuestionSelector(self, textForAnswerAtIndex: index)
selector.selected = dataSource.mutipleChoiceQuestionSelector(self, isItemSelectedAtIndex: index)
selector.isUserInteractionEnabled = true
addSubview(selector)
}
You should use :
for index in 0..<count {
let aFrame: CGRect = CGRect(x: 0, y: topMargin + heightOfSelector*CGFloat(index), width: frame.width, height: heightOfSelector)
let selector = QTSingleSelectionView(frame: aFrame)
selector.text = dataSource.mutipleChoiceQuestionSelector(self, textForAnswerAtIndex: index)
selector.selected = dataSource.mutipleChoiceQuestionSelector(self, isItemSelectedAtIndex: index)
selector.isUserInteractionEnabled = true
addSubview(selector)
}
This will call the appropriate initializer which is init(frame: CGRect) which has the initializer() inside it. But right now your code call's default init() function of the UIView which does not have your custom initialize.