UISeachController Delegate methods not called, searchbar can't become first responder - swift

Question

I'm having some difficulty getting the searchbar in my searchcontroller to become firstResponder. I've noticed the delegate methods are not being called, but the searchbar works as intended when I'm typing to filter a list of users.
Definition of searchcontroller:
lazy var searchController: UISearchController = {
let searchController = UISearchController(searchResultsController: nil)
searchController.searchResultsUpdater = self
searchController.obscuresBackgroundDuringPresentation = false
searchController.searchBar.placeholder = "Search"
return searchController
}()
Setting it up:
private func setupSearchController() {
self.navigationItem.searchController = searchController
searchController.definesPresentationContext = true
searchController.delegate = self
searchController.isActive = true
searchController.searchBar.delegate = self
searchController.searchBar.becomeFirstResponder()
}
I tried this suggestion from another SO question but the delegate method isn't being called:
func didPresentSearchController(searchController: UISearchController) {
UIView.animate(withDuration: 0.1, animations: { () -> Void in }) { (completed) -> Void in
searchController.searchBar.becomeFirstResponder()
}
}

Answer 1

The problem is you are trying to access UI element(searchbarcontroller) before UI is completely loaded.
This can be done in 2 ways
Use main queue to show keypad
private func setupSearchController() {
self.navigationItem.searchController = searchController
searchController.definesPresentationContext = true
searchController.delegate = self
searchController.isActive = true
searchController.searchBar.delegate = self
DispatchQueue.main.async {
self.searchController.searchBar.becomeFirstResponder()
}
}
With this approach keypad will be only show at one time in viewDidLoad
Show keypad in viewDidAppear
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
DispatchQueue.main.async {
self.searchController.searchBar.becomeFirstResponder()
}
}
With this approach keypad will be always shown whenever screen appears.