Game Center SwiftUI Implementation

Is there an Xcode project of "The Coast" that we can download to see how the Game Center functionality is implemented in SwiftUI? Is there anything different I would have to do if I wanted to use it in a multi-platform app? I would be interested in seeing a .swift file that has a complete Game Center implementation.
There are lots of tutorials explaining how to set up Game Center in itunesconnect and configuring it for your application in Xcode. But, the missing part for me to use Game Center from SwiftUI was that it is just too easy!

This view will authenticate the user and show their avatar once they authenticate.

Code Block
import SwiftUI
import GameKit
struct MenuView: View {
    let localPlayer = GKLocalPlayer.local
    func authenticateUser() {
        localPlayer.authenticateHandler = { vc, error in
            guard error == nil else {
                print(error?.localizedDescription ?? "")
                return
            }
            GKAccessPoint.shared.isActive = localPlayer.isAuthenticated
        }
    }
    var body: some View {
        NavigationView {
            NavigationLink(destination: GameView()) {
                Text("Play Game")
            }
        }
        .navigationViewStyle(StackNavigationViewStyle())
        .onAppear {
            authenticateUser()
        }
    }
}

Obviously, this is not production-ready code but it may help you to get started with SwiftUI and Game Center
Thank you very much! I tried so many different approches without any luck... so easy!

Do you have examples of how to implement matchmaking, leaderboard, and data sharing with SwiftUI?
I think the CHaririson's answer isn't complete. We should present the View Controller (vc) somewhere. It's provided to authenticateHandler in order to give user chance to sign in.
Game Center SwiftUI Implementation
 
 
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