UIView not removed in iOS13, It works in iOS 12

Question

I've app initially developed in xcode 10 but I've upgrade to xcode 11 then Loader not hiding check below code

import UIKit

class LoadingView: UIView {

//MARK:  IndicatoreShow
class func Show() {
    DispatchQueue.main.async {
        let loadingView = LoadingView(frame: UIScreen.main.bounds)
        loadingView.backgroundColor = UIColor(red: 0, green: 0, blue: 0, alpha: 0.8)
        if let _lastWindow = UIApplication.shared.windows.last {
            if !_lastWindow.subviews.contains(where: { $0 is LoadingView }) {
                _lastWindow.endEditing(true)
                _lastWindow.addSubview(loadingView)
            }
        }
        loadingView.addFadeAnimationWithFadeType(.fadeIn)
        let indicator = UIActivityIndicatorView(frame: CGRect(x: 0, y: 0, width: 30, height: 30))
        indicator.center = loadingView.center
        indicator.tintColor = .white
        if UI_USER_INTERFACE_IDIOM() == .pad {
            indicator.style = .whiteLarge
        } else {
            indicator.style = .white
        }
        indicator.startAnimating()
        loadingView.addSubview(indicator)
    }
}

//MARK:  IndicatoreHide
class func Hide() {
    DispatchQueue.main.async {
        if let _lastWindow = UIApplication.shared.windows.last {
            for subview in _lastWindow.subviews {
                if let loadingView = subview as? LoadingView {
                    loadingView.addFadeAnimationWithFadeType(.fadeOut)
                }
            }
        }
    }
}
}

 //MARK:  Animation Enum
  enum FadeType {
    case fadeIn
    case fadeOut
  }

extension UIView {

//MARK:  AnimationWith Fade
func addFadeAnimationWithFadeType(_ fadeType: FadeType) {

    switch fadeType {
    //MARK:  fade IN
    case .fadeIn:

        DispatchQueue.main.async {
            self.alpha = 0.0
            UIView.animate(withDuration: 0.5, animations: { () -> Void in
                self.alpha = 1.0
            })
        }
    //MARK:  Fade Out
    case .fadeOut:

        UIView.animate(withDuration: 0.5, animations: { () -> Void in
            DispatchQueue.main.async {
                self.alpha = 0.0
            }
        }, completion: { (finished) -> Void in
            if finished {
                self.removeFromSuperview()
            }
        })
    }
}
}

And I used LoadingView.Show() //this is working LoadingView.Hide() // this is not working in iOS 13 What should I change in code because many code are not working in iOS 13 like status bar background color

Answer 1

In the code you posted, your "fade out" block looks like this:

    //MARK:  Fade Out
    case .fadeOut:

        UIView.animate(withDuration: 0.5, animations: { () -> Void in
            DispatchQueue.main.async {
                self.alpha = 0.0
            }
        }, completion: { (finished) -> Void in
            if finished {
                self.removeFromSuperview()
            }
        })
    }

There, the only line of code wrapped in DispatchQueue.main.async is self.alpha = 0.0 . Everything else will be executed on the thread from which it was called.

Changing that case to:

    //MARK:  Fade Out
    case .fadeOut:

        DispatchQueue.main.async {
            UIView.animate(withDuration: 0.5, animations: { () -> Void in
                self.alpha = 0.0
            }, completion: { (finished) -> Void in
                if finished {
                    self.removeFromSuperview()
                }
            })
        }

    }

will likely solve the issue.