UIActivityIndicator add AppDelegate - ios

Question

I want to run UIActivityIndicator when the application is opened. How can I do this? My code is the way I share it down there. I want this code to work when Launchscreen opens.
#objc func buttonTapped(_ sender: UIButton) {
let size = CGSize(width: 30, height: 30)
let selectedIndicatorIndex = sender.tag
let indicatorType = presentingIndicatorTypes[selectedIndicatorIndex]
startAnimating(size, message: "Loading...", type: indicatorType, fadeInAnimation: nil)
DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 1.5) {
NVActivityIndicatorPresenter.sharedInstance.setMessage("Authenticating...")
}
DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 3) {
self.stopAnimating(nil)
}
}
for (index, indicatorType) in presentingIndicatorTypes.enumerated() {
let x = 150
let y = 250
let frame = CGRect(x: x, y: y, width: 100, height: 100)
let activityIndicatorView = NVActivityIndicatorView(frame: frame,
type: .orbit)
let animationTypeLabel = UILabel(frame: frame)
activityIndicatorView.padding = 20
if indicatorType == NVActivityIndicatorType.orbit {
activityIndicatorView.padding = 0
}
self.view.addSubview(activityIndicatorView)
self.view.addSubview(animationTypeLabel)
activityIndicatorView.startAnimating()
let button: UIButton = UIButton(frame: frame)
button.tag = index
#if swift(>=4.2)
button.addTarget(self,
action: #selector(buttonTapped(_:)),
for: .touchUpInside)
#else
button.addTarget(self,
action: #selector(buttonTapped(_:)),
for: UIControlEvents.touchUpInside)
#endif
self.view.addSubview(button)
}

Answer 1

What you are trying to achieve is to show UIActivityIndicator during launch screen, which is unfortunately NOT possible. If you want to do any animations on launch screen, use your first view controller as splash screen and redirect to main screen when animation on splash screen ends.
Some ideas:
Create separate loading page and call it from didFinishLaunchingWithOptions method in App delegate
Add loading indicator (can be whatever you want) to it
Set timer of 2-3 seconds, when it ends redirect to your main screen
P.S. delaying application launch just to show users some awesome animation/loading screen is not a good idea. For a first time app users it might seem cool and such, but with an extensive use of an application users might get frustrated waiting even few seconds each time an application is launched.
Good luck :)