my UITapGestureRecognizer not working

Question

I defined a class named Bubble, and there's a function named CreateBubbleView and I add an tapGestureRecognizer to it.But it is not working. Here's my code.

var frame: CGRect = CGRect.zero
var shapeLayer = CAShapeLayer()
var bubbleView: UIView!

func CreateBubbleView(arcCenter: CGPoint,radius: CGFloat) {
    bubbleView = UIView(frame: frame)
    bubbleView.backgroundColor = UIColor.black

    shapeLayer = CAShapeLayer()
    let bubblePath = UIBezierPath(arcCenter: .zero, radius: radius, startAngle: 0, endAngle: 2 * CGFloat.pi, clockwise: true)
    shapeLayer.path = bubblePath.cgPath
    shapeLayer.position = arcCenter
    shapeLayer.fillColor = UIColor(red: 1, green: 0.8, blue: 0.09, alpha: 0.5).cgColor

    bubbleView.layer.addSublayer(shapeLayer)
    let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(HandleTap))
    bubbleView.addGestureRecognizer(tapGestureRecognizer)

}

@objc func HandleTap() {
    print(123)
}

and in viewController I coded

override func viewDidLoad() {
    super.viewDidLoad()

    let bubble_0 = Bubble()
    bubble_0.frame = view.frame
    bubble_0.CreateBubbleView(arcCenter: view.center, radius: 80)
    let bubbleView_0 = bubble_0.bubbleView
    view.addSubview(bubbleView_0!)
}

Answer 1

let bubbleView_0 = bubble_0.bubbleView
view.addSubview(bubbleView_0!)

I notice you created bubble_0, but only add its bubbleView. bubble_0 will be released(according to ARC). So your tap will no longer have a target. To fix this, you can hold bubble_0 in your view controller.

var bubble_0: Bubble!    
override func viewDidLoad() {
    super.viewDidLoad()

    bubble_0 = Bubble()
    bubble_0.frame = view.frame
    bubble_0.CreateBubbleView(arcCenter: view.center, radius: 80)
    let bubbleView_0 = bubble_0.bubbleView
    view.addSubview(bubbleView_0!)
}