upstream-flutter-samples/add_to_app/books/ios_books/IosBooks/AppDelegate.swift

// Copyright 2020 The Flutter team. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import Flutter
import UIKit

@main
class AppDelegate: UIResponder, UIApplicationDelegate {
  lazy var engine: FlutterEngine = {
    let result = FlutterEngine.init(name: "Books")
    // This could be `run` earlier in the app to avoid the overhead of doing it the first time the
    // engine is needed.
    result.run()
    return result
  }()

  func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
  ) -> Bool {
    return true
  }

  func application(
    _ application: UIApplication, configurationForConnecting connectingSceneSession: UISceneSession,
    options: UIScene.ConnectionOptions
  ) -> UISceneConfiguration {
    return UISceneConfiguration(
      name: "Default Configuration", sessionRole: connectingSceneSession.role)
  }

  func application(
    _ application: UIApplication, didDiscardSceneSessions sceneSessions: Set<UISceneSession>
  ) {
  }
}