Swift: Can't dismiss view controller - ios

Question

I have a SwiftUI project in which I'm presenting a view controller to display an advertisement via MoPub.
Everything works as expected except one thing: when I tap the ad's close button, the ad itself closes but the black screen behind the ad continues to show. I guess the view controller is not being dismissed (but the completion block for dismiss does run).
Here's my code:
class InterstitialAds: UIViewController, MPInterstitialAdControllerDelegate {
var moPubView: MPInterstitialAdController?
func viewControllerForPresentingModalView() -> UIViewController! {
return self
}
//Called when you tap the ad's close button:
func interstitialWillDismiss(_ interstitial: MPInterstitialAdController) {
dismissControllerWithoutReward()
}
func showAd() {
let topViewController = UIApplication.shared.windows.filter {$0.isKeyWindow}.first?.rootViewController
self.modalPresentationStyle = .fullScreen
topViewController?.present(self, animated: true) {}
}
func dismissControllerWithoutReward() {
self.dismiss(animated: true) {
print("dismissControllerWithoutReward()") //Successfully prints to console
}
}
override func viewDidLoad() {
let adId = "4f117153f5c24fa6a3a92b818a5eb630" //Test ad unit
self.moPubView = MPInterstitialAdController(forAdUnitId: adId)
if let v = self.moPubView {
v.delegate = self
v.loadAd()
DispatchQueue.main.asyncAfter(deadline: .now() + 1.0) {
v.show(from: self)
}
}
super.viewDidLoad()
}
}
Question:
Why isn't the view controller being dismissed, despite the successful call to dismiss?
Thank you!
Edit:
Interestingly, if I wait 0.5 seconds before trying to dismiss the view controller, it dismisses as desired. So, now I've got this code in interstitialWillDismiss(_:) (but I still want to know why this is happening):
func interstitialWillDismiss(_ interstitial: MPInterstitialAdController) {
DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
self.dismissControllerWithoutReward()
}
}

Answer 1

For getting clear implementation and expected behavior you should wrap InterstitialAds controller in UIViewControllerRepresentable, then connect you SwiftUI side with some InterstitialAdsView which implements from UIViewControllerRepresentable via some isPresented flag binding.
Short example:
class InterstitialAds: UIViewController {
let onFlowCompleted: () -> Void
init(onFlowCompleted: #escaping () -> Void) {
self.onFlowCompleted = onFlowCompleted
// ...
}
override func dismiss(animated flag: Bool, completion: (() -> Void)? = nil) {
onFlowCompleted()
// or somewhere else ...
}
}
struct HomeView: View {
#State var shouldShowInterstitialView = false
var body: some View {
Button {
shouldShowInterstitialView = true
} label: {
Text("Show Ad")
}
.fullScreenCover(isPresented: $shouldShowInterstitialView) {
InterstitialAdsView {
shouldShowInterstitialView = false
}
}
}
}
struct InterstitialAdsView: UIViewControllerRepresentable {
// #Environment(\.presentationMode) var presentationMode
// or
// #Binding var isPresented: Bool
// or
let onFlowCompleted: () -> Void
func makeUIViewController(context: Context) -> InterstitialAds {
InterstitialAds(onFlowCompleted: onFlowCompleted)
}
func updateUIViewController(_ uiViewController: InterstitialAds, context: Context) {
// update if needed
}
}