SceneDelegate.swift of SwiftUI project

SceneDelegate.swift

import UIKit
import SwiftUI

class SceneDelegate: UIResponder, UIWindowSceneDelegate {

    var window: UIWindow?

    func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
        let context = (UIApplication.shared.delegate as! AppDelegate).persistentContainer.viewContext

        let contentView = ContentView().environment(\.managedObjectContext, context)

        if let windowScene = scene as? UIWindowScene {
            let window = UIWindow(windowScene: windowScene)
            window.rootViewController = UIHostingController(rootView: contentView)
            self.window = window
            window.makeKeyAndVisible()
        }
    }

    func sceneDidDisconnect(_ scene: UIScene) {}

    func sceneDidBecomeActive(_ scene: UIScene) {}

    func sceneWillResignActive(_ scene: UIScene) {}

    func sceneWillEnterForeground(_ scene: UIScene) {}

    func sceneDidEnterBackground(_ scene: UIScene) {
        (UIApplication.shared.delegate as? AppDelegate)?.saveContext()
    }


}