How to add Google AdMob ad banner to SwiftUI with Apple Tracking Transparency (ATT) framework

Google AdMob

Ad units > Add ad unit > Banner

App ID: ca-app-pub-1111222233334444~1234567890

Ad unit ID: ca-app-pub-1111222233334444/9876543210

XCode

XCode > File > Add Package Dependencies

Add Package: swift-package-manager-google-mobile-ads (Google Mobile Ads SDK)

You should be able to see the added packages in:
1. Navigator under "Package Dependencies" e.g.
```
> 📦 GoogleMobileAds 11.8.0
> 📦 GoogleUserMessagingPlatform 2.5.0
```
If you can't see "Package Dependenceis" in the Navigator, try restarting the XCode
1. Project -> Targets -> General tap -> "Frameworks, Libraries, and Embedded Content"
```
🏛️ GoogleMobileAds
```
Add below to the Info.plist

    Add Key: "GADApplicationIdentifier"
    Value: "ca-app-pub-1111222233334444~1234567890"

How to add to the Info.plist:

Select project in the Navigation -> Targets > Info > Custom macOS Application Target Properties: Hover over pre-existing Keys and click (+) -> fill in the Key and Value pair. This will create Info on the Navigator if not already exists. This can be seen as Info.plist in the Finder.
If Info exists on the Navigator: right click -> Open As -> Source Code; add to the XML file.

<dict>
	<key>GADApplicationIdentifier</key>
	<string>ca-app-pub-1639129328565259~1986806680</string>
...
</dict>

Swift files

File contents to be updated as my code evolves

MainApp.swift

Get the testDeviceIdentifiers from the warnings: XCode -> Debug Area -> Console.

// MainApp.swift
 
import SwiftUI
import GoogleMobileAds
 
@main
struct MainApp: App {
    @UIApplicationDelegateAdaptor(AppDelegate.self) var appDelegate
    private let testDeviceIdentifiers = [ "..." ]
 
    init() {
        GADMobileAds.sharedInstance().start(completionHandler: nil)
        GADMobileAds.sharedInstance().requestConfiguration.testDeviceIdentifiers = self.testDeviceIdentifiers
    }
 
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

AdBannerView.swift

// AdBannerView.swift
 
import SwiftUI
import GoogleMobileAds
import AppTrackingTransparency
 
let AD_UNIT_ID = "ca-app-pub-1111222233334444/9876543210"
 
struct AdBannerViewWrapper: View {
    @Environment(\.scenePhase) private var scenePhase
    @State private var shouldReload = false
    @State private var adHeight: CGFloat = 50
 
    var body: some View {
        VStack(spacing: 0) {
            Rectangle()
                .fill(.gray.opacity(0.1))
                .frame(height: 8)
 
            AdBannerView(shouldReload: $shouldReload)
                .frame(height: adHeight)
                .background(.gray.opacity(0.1))
        }
        .onAppear {
            Task {
                if ATTrackingManager.trackingAuthorizationStatus == .notDetermined {
                    await ATTrackingManager.requestTrackingAuthorization()
                }
            }
            adHeight = GADPortraitAnchoredAdaptiveBannerAdSizeWithWidth(UIScreen.main.bounds.width).size.height
        }
        .onChange(of: scenePhase) {
            if scenePhase == .active {
                DispatchQueue.main.async {
                    shouldReload = true
                }
            }
        }
    }
}
 
struct AdBannerView: UIViewRepresentable {
    @Binding var shouldReload: Bool
    @State private var isTrackingAuthorized = false
 
    func makeUIView(context: Context) -> GADBannerView {
        let adSize = GADPortraitAnchoredAdaptiveBannerAdSizeWithWidth(UIScreen.main.bounds.width)
        let bannerView = GADBannerView(adSize: adSize)
        bannerView.adUnitID = AD_UNIT_ID
        bannerView.rootViewController = getRootViewController()
        return bannerView
    }
 
    func updateUIView(_ uiView: GADBannerView, context: Context) {
        if shouldReload {
            Task {
                if ATTrackingManager.trackingAuthorizationStatus == .notDetermined {
                    let status = await ATTrackingManager.requestTrackingAuthorization()
                    DispatchQueue.main.async {
                        isTrackingAuthorized = status == .authorized
                        loadAd(bannerView: uiView)
                        shouldReload = false
                    }
                } else {
                    DispatchQueue.main.async {
                        isTrackingAuthorized = ATTrackingManager.trackingAuthorizationStatus == .authorized
                        loadAd(bannerView: uiView)
                        shouldReload = false
                    }
                }
            }
        }
    }
 
    private func loadAd(bannerView: GADBannerView) {
        let request = GADRequest()
        if !isTrackingAuthorized {
            let extras = GADExtras()
            extras.additionalParameters = ["npa": "1"]
            request.register(extras)
        }
        bannerView.load(request)
    }
 
    private func getRootViewController() -> UIViewController? {
        guard let windowScene = UIApplication.shared.connectedScenes
            .first(where: { $0.activationState == .foregroundActive}) as? UIWindowScene else {
            return nil
        }
        return windowScene.windows.first?.rootViewController
    }
}

Use in view

AdBannerViewWrapper()

Make sure Test mode is displayed in the ad banner. If not (e.g. first time, new install), grab a new testDeviceIdentifiers.

XCode Console:

<Google> To get test ads on this device, set:
Objective-C
	GADMobileAds.sharedInstance.requestConfiguration.testDeviceIdentifiers = @[ @"1234" ];
Swift
	GADMobileAds.sharedInstance().requestConfiguration.testDeviceIdentifiers = [ "1234" ]

Info.plist

Enable SKAdNetwork to track conversions