How do I show a view on dismiss of a video reward ad?

In this SwiftUI code, when the play button is tapped, a video reward ad is shown. After this video ad has been dismissed, I want to show a view saying ("you watched an ad").

The view I want to show after the video reward ad has been dismissed will explain the rewards to the user and will be dismissed by an "x" in the top right.

Here is my code:

struct EarnRewards: View {
    
    private var rewardedAdView = RewardedAdView()
    
    fileprivate func videoAdButton(_ closure: @escaping () -> Void) -> some View {
        return Button {
            print("Tapped Video Button")
            closure()
        } label: {
            
            Image(systemName: "play.fill")
                .foregroundColor(.black)
        }
    }
    
    var body: some View {
        
        VStack {
           
            videoAdButton {
                self.rewardedAdView.showAd {
                    print("Reward the user")
                }
            }
        }
        
    }
}

final class RewardedAdView: NSObject, GADFullScreenContentDelegate {

    var rewardedAd: GADRewardedAd?
    var rewardFunction: (() -> Void)? = nil

    override init() {
        super.init()
        loadRewarded()
    }

    func loadRewarded(){
        let request = GADRequest()
        GADRewardedAd.load(withAdUnitID: Constants.AdMob.rewardedAdUnitId,
                                  request: request, completionHandler: { (ad, error) in
                                    if let error = error {
                                      print("Rewarded ad failed to load with error: \(error.localizedDescription)")
                                      return
                                    }
                                    self.rewardedAd = ad
                                    self.rewardedAd?.fullScreenContentDelegate = self
                                  })
    }

    func showAd(_ rewardFunction: @escaping () -> Void){
        if let ad = rewardedAd,
           let root = UIApplication.shared.windows.first?.rootViewController {
              ad.present(fromRootViewController: root,
                       userDidEarnRewardHandler: {
                            let reward = ad.adReward
                            print(reward)
                            rewardFunction()
                       })
          } else {
            print("Ad wasn't ready")
          }
    }

    func rewardedAd(_ rewardedAd: GADRewardedAd, userDidEarn reward: GADAdReward) {
        if let rewardFunction = rewardFunction {
            rewardFunction()
        }
    }

    /// Tells the delegate that the ad failed to present full screen content.
    func ad(_ ad: GADFullScreenPresentingAd, didFailToPresentFullScreenContentWithError error: Error) {
      print("Ad did fail to present full screen content.")
    }

    /// Tells the delegate that the ad dismissed full screen content.
    func adDidDismissFullScreenContent(_ ad: GADFullScreenPresentingAd) {
      print("Ad did dismiss full screen content.")
    }
}

How do I display a view on dismiss of the video ad?

You can add a @State property in your EarnRewards View which will track the dismiss of the video ad

// Define this
@State private var adDismissed = false

 var body: some View {
ZStack {
        VStack {
            if !adDismissed {
                videoAdButton {
                    self.rewardedAdView.showAd {
                        print("Reward the user")
                        self.adDismissed = true
                    }
                }
            }
        }
        
        if adDismissed {
            VStack {
                Text("You watched an ad")
                Button(action: {
                    self.adDismissed = false
                }) {
                    Image(systemName: "xmark.circle.fill")
                }
            }
            .padding()
            .background(Color.white)
            .cornerRadius(10)
        }
    }
}