A Button Gets Touch Event of Multiple Views (though not subview!)

include_touch_of_other_views.swift

import UIKit

class CustomButton {
  var containingTouchViews: [UIView] = []

  override func point(inside point: CGPoint, with event: UIEvent?) -> Bool {
    self.containingTouchViews
      .map { view in 
        view.frame.contains(self.convert(point, to: view))
          // below codes are optional
          && view.isUserInteractionEnabled
          && !view.isHidden
          && view.alpha > 0
       }
      .filter { $0 }
      .isNotEmpty
    || super.point(inside: point, with: event)
  }
}

// Usage
class ViewController: UIViewController {
  let button = CustomButton()
  let otherView = UIView()
  ...
  override func viewDidLoad() {
    super.viewDidLoad()
    
    self.button.containingTouchViews.append(self.otherView)
    // then, otherView's touch event passes to the button
  }
}