[swift5]iOSアプリでローカル通知を実装

ローカル通知を実装する方法を紹介します！

動作環境

対象	バージョン
iOS	13.3.1
macOS	Catalina 10.15.3
Xcode	11.3.1
Swift	5.1.3

実装の方法

ソースコード

AppDelegate.swift

import UIKit
import UserNotifications

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        // Override point for customization after application launch.

        // 通知許可の取得
        UNUserNotificationCenter.current().requestAuthorization(
        options: [.alert, .sound, .badge]){
            (granted, _) in
            if granted{
                UNUserNotificationCenter.current().delegate = self
            }
        }
        return true
    }

    // MARK: UISceneSession Lifecycle

    func application(_ application: UIApplication, configurationForConnecting connectingSceneSession: UISceneSession, options: UIScene.ConnectionOptions) -> UISceneConfiguration {
        // Called when a new scene session is being created.
        // Use this method to select a configuration to create the new scene with.
        return UISceneConfiguration(name: "Default Configuration", sessionRole: connectingSceneSession.role)
    }

    func application(_ application: UIApplication, didDiscardSceneSessions sceneSessions: Set<UISceneSession>) {
        // Called when the user discards a scene session.
        // If any sessions were discarded while the application was not running, this will be called shortly after application:didFinishLaunchingWithOptions.
        // Use this method to release any resources that were specific to the discarded scenes, as they will not return.
    }

}

extension AppDelegate: UNUserNotificationCenterDelegate {
    func userNotificationCenter(
        _ center: UNUserNotificationCenter,
        willPresent notification: UNNotification,
        withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void)
    {
        // アプリ起動時も通知を行う
        completionHandler([ .badge, .sound, .alert ])
    }
}

ViewController.swift

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
    }

    /// ローカル通知ボタンを押下した際の処理
    /// - Parameter sender: ローカル通知ボタン
    @IBAction func localPush(_ sender: Any) {
        let content = UNMutableNotificationContent()
        content.title = "お知らせ"
        content.body = "ボタンを押しました。"
        content.sound = UNNotificationSound.default

        // 直ぐに通知を表示
        let request = UNNotificationRequest(identifier: "immediately", content: content, trigger: nil)
        UNUserNotificationCenter.current().add(request, withCompletionHandler: nil)
    }
}