halkyon/apps/todo/halkyon_todo_flutter/ios/Runner/AppDelegate.swift

import Flutter
import UIKit
import UserNotifications
// For FlutterLocalNotificationsPlugin.setPluginRegistrantCallback.
import flutter_local_notifications

@main
@objc class AppDelegate: FlutterAppDelegate, FlutterImplicitEngineDelegate {
  override func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
  ) -> Bool {
    // Reminders show while the app is open too (flutter_local_notifications).
    UNUserNotificationCenter.current().delegate = self as? UNUserNotificationCenterDelegate
    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
  }

  func didInitializeImplicitFlutterEngine(_ engineBridge: FlutterImplicitEngineBridge) {
    // A reminder snoozed with the app closed is scheduled again in an
    // isolate of the plugin's, which needs the plugins too (ADR 0033, D4).
    FlutterLocalNotificationsPlugin.setPluginRegistrantCallback { (registry) in
      GeneratedPluginRegistrant.register(with: registry)
    }
    GeneratedPluginRegistrant.register(with: engineBridge.pluginRegistry)
  }
}