packages/flutter_tools/templates/create/ios-swift.tmpl/Runner/AppDelegate.swift

import UIKit
import Flutter

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate {
  override func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?
  ) -> Bool {
    GeneratedPluginRegistrant.register(with: self);
    return super.application(application, didFinishLaunchingWithOptions: launchOptions);
  }
}