Has isThumbVisible bug when change dynamically #38

import UIKit

import Rideau

final class ViewController: UIViewController {

  @IBOutlet weak var box1: UIView!
  
  @IBOutlet weak var box2: UIView!
  
  private let rideauView = RideauView(frame: .zero) { (config) in
    config.topMarginOption = .fromSafeArea(0)
    config.snapPoints = [.pointsFromBottom(150), .pointsFromBottom(250), .pointsFromBottom(700), .full]
  }

  let container = RideauMaskedCornerRoundedViewController()
  lazy var defaultCornerRadius = container.contentView.cornerRadius
  
  override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    view.addSubview(rideauView)

    rideauView.frame = view.bounds
    rideauView.autoresizingMask = [.flexibleWidth, .flexibleHeight]

    let controller = UIStoryboard.init(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "MainMenuViewController") as! MainMenuViewController

    container.isThumbVisible = true
    container.setBodyViewController(controller)
    container.willMove(toParent: self)
    addChild(container)
    
    rideauView.containerView.set(bodyView: container.view, resizingOption: .resizeToVisibleArea)
    rideauView.isTrackingKeyboard = false
    rideauView.delegate = self
  }
  
  override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(animated)
    print("viewDidAppear")
  }
  
  @IBAction func didTapChangeButton(_ sender: Any) {
    self.box1.backgroundColor = .blue
    self.box2.backgroundColor = .blue
  }
}

extension ViewController : RideauViewDelegate {
  func rideauView(_ rideauView: RideauView, animatorsAlongsideMovingIn range: ResolvedSnapPointRange) -> [UIViewPropertyAnimator] {
    
    switch (range.start.source, range.end.source) {
    case (.fraction(1), .fraction(0.7)):
      
      let animator1 = UIViewPropertyAnimator(duration: 0.3, curve: .easeInOut) {
        self.box1.alpha = 0.3
      }
      
      let animator2 = UIViewPropertyAnimator(duration: 0.3, curve: .easeInOut) {
        rideauView.backgroundColor = UIColor(white: 0, alpha: 0.3)
      }
      
      return [animator1, animator2]
      
    case (.fraction(0.7), .autoPointsFromBottom):
      let animator = UIViewPropertyAnimator(duration: 0.3, curve: .easeInOut) {
        self.box2.alpha = 0.3
      }
      return [animator]
      
    default:
      return []
    }
  }
  
  func rideauView(_ rideauView: RideauView, willMoveTo snapPoint: RideauSnapPoint) {
    switch snapPoint {
    case .full:
      container.contentView.cornerRadius = 0
      container.isThumbVisible = false // This case has layout bug
    default:
      container.contentView.cornerRadius = defaultCornerRadius
      container.isThumbVisible = true
    }
  }
}