【Swift】UserNotification(ローカル通知)の使い方

完成図 

 ↓destination == "Ken"の時

解説

 ※注意点

・今回はバックグラウンドでの実装

・”送信する”を押して、すぐにアプリを閉じないと、ローカル通知が発動しない

・発動すれば、画面上部 & 通知センターに表示される

ストーリーボード

ソースコード

import UIKit
import UserNotifications

class ViewController: UIViewController, UITextFieldDelegate {
    
    @IBOutlet weak var nameTextField: UITextField!
    @IBOutlet weak var honbunTextField: UITextView!
    
    //送り先を受け取る
    var destination = ""
    
    //本文を受け取る
    var message = ""
    
    //identifier用の変数
    let NotificationIdentifier = "ID"
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        //デリゲートを取得
        nameTextField.delegate = self
        
    }
    
    @IBAction func send(_ sender: Any) {
        //送り先を代入する
        destination = nameTextField.text!
        //本文を代入する
        message = honbunTextField.text!
        //メッセージを送信する
        gopush()
    }
    
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    //ローカル通知の許可等
    func gopush() {
        UNUserNotificationCenter.current().getNotificationSettings { (settings) in
            //もし通知が許可されているなら
            if settings.authorizationStatus == .authorized {
                //通知
                self.push()
                
            //もし通知が許可されてないなら
            } else {
                
                UNUserNotificationCenter.current().requestAuthorization(
                    options: [.sound,.badge,.alert],completionHandler: { (granted, error) in
                        
                    if let error = error {
                        print(error)
                    } else {
                        if (granted) {
                            self.push()
                        }
                    }
                        
                })
                
            }
            
        }
        
    }
    
    //ローカル通知内での処理
    func push() {
        
        //指定した文章と同じかどうか
        if message == "" {
            
            //UserNotificationのインスタンス
            let content = UNMutableNotificationContent()
        
            //送り主で条件分岐
            switch destination {
            case "Amy":
                //メッセージのタイトル
                content.title = "All right!!"
                //メッセージの本文
                content.body = "I will put on my favorite clothes!"
                //通知に貼り付ける画像のURL
                if let url = Bundle.main.url(forResource: "Amy", withExtension: "png"),let attach = try? UNNotificationAttachment(identifier: NotificationIdentifier, url: url, options: nil) {
                    content.attachments.append(attach)
                }
            case "Karen":
                content.title = "OK!"
                content.body = "I'm looking forward to watching a movie with everyone!"
                if let url = Bundle.main.url(forResource: "Karen", withExtension: "png"), let attach = try? UNNotificationAttachment(identifier: NotificationIdentifier, url: url, options: nil) {
                    content.attachments.append(attach)
                }
            case "Ken":
                content.title = "Oh Yes!"
                content.body = "Let's release the stress accumulated in the exam tomorrow at once!"
                if let url = Bundle.main.url(forResource: "Ken", withExtension: "png"), let attach = try? UNNotificationAttachment(identifier: NotificationIdentifier, url: url, options: nil) {
                    content.attachments.append(attach)
                }
            case "Mike":
                content.title = "I want to go early"
                content.body = "Finally I can get out of boring lessons and I can not wait for tomorrow's event"
                if let url = Bundle.main.url(forResource: "Mike", withExtension: "png"), let attach = try? UNNotificationAttachment(identifier: NotificationIdentifier, url: url, options: nil) {
                    content.attachments.append(attach)
                }
            default:
                content.title = "It is a mistake email."
                content.body = "Who are you? It is fine if sales"
            }
        
        //5秒後に通知
        let trigger = UNTimeIntervalNotificationTrigger(timeInterval: 3.0, repeats: false)
        
        //トリガーと内容を内包
        let notificationrequest = UNNotificationRequest(identifier: NotificationIdentifier,
                                                        content: content, trigger: trigger)
        
        //エラー処理
        UNUserNotificationCenter.current().add(notificationrequest) { (error) in
            if let error = error {
                print(error)
            } else {
                print("通知されました")
            }
        }
            
        } else {
            print("もう一度やり直してください。")
        }
        
    }
    
}