Working with Notifications

import Foundation

let notification = Notification(name: .init("MyNotification"), object: nil, userInfo: ["message": "Hello World"])
NotificationCenter.default.post(notification)

import Foundation

let observer = NotificationCenter.default.addObserver(
    forName: .init("MyNotification"),
    object: nil,
    queue: nil
) { notification in
    if let message = notification.userInfo?["message"] as? String {
        print("Received: \(message)")
    }
}

// To remove observer later
// NotificationCenter.default.removeObserver(observer)

import UIKit

class ViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        
        NotificationCenter.default.addObserver(
            self,
            selector: #selector(handleNotification),
            name: NSNotification.Name("CustomNotification"),
            object: nil
        )
    }
    
    @objc func handleNotification(_ notification: Notification) {
        print("Received notification: \(notification)")
    }
    
    deinit {
        NotificationCenter.default.removeObserver(self)
    }
}

import UserNotifications

let content = UNMutableNotificationContent()
content.title = "Meeting Reminder"
content.body = "Your meeting starts in 10 minutes."
content.sound = .default
content.badge = 1

let trigger = UNTimeIntervalNotificationTrigger(timeInterval: 5, repeats: false)
let request = UNNotificationRequest(identifier: "meetingReminder", content: content, trigger: trigger)

UNUserNotificationCenter.current().add(request) { error in
    if let error = error {
        print("Error posting notification: \(error)")
    } else {
        print("Notification posted successfully")
    }
}

class MyViewController: UIViewController {
    private var observer: Any?

    override func viewDidLoad() {
        super.viewDidLoad()
        observer = NotificationCenter.default.addObserver(
            forName: .myNotification,
            object: nil,
            queue: .main
        ) { _ in
            print("Notification received")
        }
    }

    deinit {
        if let observer = observer {
            NotificationCenter.default.removeObserver(observer)
        }
    }
}

class MyViewController: UIViewController {
    private var observer: Any?

    override func viewDidLoad() {
        super.viewDidLoad()
        observer = NotificationCenter.default.addObserver(
            forName: .myNotification,
            object: nil,
            queue: .main
        ) { _ in
            print("Notification received")
        }
    }

    func stopListening() {
        NotificationCenter.default.removeObserver(
            observer!,
            name: .myNotification,
            object: nil
        )
    }
}

let userInfo = [
    "message": "You have a new message",
    "id": 456
]

let notification = UNMutableNotificationContent()
notification.title = "New Message"
notification.body = "You have a new message"
notification.userInfo = userInfo

let request = UNNotificationRequest(
    identifier: "messageNotification",
    content: notification,
    trigger: nil
)

UNUserNotificationCenter.current().add(request) { error in
    if let error = error {
        print("Error posting notification: \(error)")
    }
}

func userNotificationCenter(
    _ center: UNUserNotificationCenter,
    didReceive response: UNNotificationResponse,
    withCompletionHandler completionHandler: @escaping () -> Void
) {
    let userInfo = response.notification.request.content.userInfo
    
    if let message = userInfo["message"] as? String {
        print("Received message: \(message)")
    }
    
    if let id = userInfo["id"] as? Int {
        print("Received ID: \(id)")
    }
    
    completionHandler()
}

import UserNotifications

let content = UNNotificationContent(
    title: "Reminder",
    body: "Don't forget to complete the task.",
    sound: .default
)

let trigger = UNTimeIntervalTrigger(timeInterval: 5, repeats: false)
let request = UNNotificationRequest(identifier: "reminder", content: content, trigger: trigger)

UNUserNotificationCenter.current().add(request) { error in
    if let error = error {
        print("Error scheduling notification: \(error)")
    } else {
        print("Notification scheduled successfully")
    }
}

import UserNotifications

func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
    let userInfo = response.notification.request.content.userInfo
    print("User tapped notification with info: \(userInfo)")
    completionHandler()
}

import UserNotifications

func scheduleNotification() {
    let content = UNMutableNotificationContent()
    content.title = "Meeting Reminder"
    content.body = "Your meeting starts in 5 minutes."
    content.sound = .default

    let trigger = UNTimeIntervalNotificationTrigger(timeInterval: 300, repeats: false)
    let request = UNNotificationRequest(identifier: "meetingReminder", content: content, trigger: trigger)

    UNUserNotificationCenter.current().add(request) { error in
        if let error = error {
            print("Error scheduling notification: \(error)")
        }
    }
}

let acceptAction = UNNotificationAction(
    identifier: "ACCEPT_ACTION",
    title: "Accept",
    options: [.foreground]
)

let declineAction = UNNotificationAction(
    identifier: "DECLINE_ACTION",
    title: "Decline",
    options: [.destructive]
)

let meetingCategory = UNNotificationCategory(
    identifier: "MEETING_INVITATION",
    actions: [acceptAction, declineAction],
    intentIdentifiers: [],
    options: []
)

let center = UNUserNotificationCenter.current()
center.setNotificationCategories([meetingCategory])

func userNotificationCenter(
    _ center: UNUserNotificationCenter,
    didReceive response: UNNotificationResponse,
    withCompletionHandler completionHandler: @escaping () -> Void
) {
    let actionIdentifier = response.actionIdentifier
    switch actionIdentifier {
    case "ACCEPT_ACTION":
        print("Meeting accepted")
    case "DECLINE_ACTION":
        print("Meeting declined")
    default:
        break
    }
    completionHandler()
}

import UserNotifications

func requestNotificationPermission() {
    let options: UNAuthorizationOptions = [.alert, .sound, .badge]
    UNUserNotificationCenter.current().requestAuthorization(options: options) { granted, error in
        if granted {
            print("Notification permission granted.")
        } else {
            print("Notification permission denied.")
        }
    }
}

import UserNotifications

func schedulePushNotification() {
    let content = UNMutableNotificationContent()
    content.title = "Reminder"
    content.body = "Don't forget to complete your task."
    content.sound = .default

    let trigger = UNTimeIntervalTrigger(timeInterval: 5, repeats: false)
    let request = UNNotificationRequest(identifier: "reminder", content: content, trigger: trigger)

    UNUserNotificationCenter.current().add(request) { error in
        if let error = error {
            print("Error scheduling notification: \(error)")
        } else {
            print("Notification scheduled successfully.")
        }
    }
}

import UserNotifications

func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable: Any], fetchCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {
    print("Received remote notification: \(userInfo)")
    
    // Process the notification data
    if let aps = userInfo["aps"] as? [String: Any] {
        if let alert = aps["alert"] as? [String: Any] {
            print("Alert title: \(alert["title"] ?? "")")
        }
    }
    
    completionHandler(.newData)
}

import UserNotifications

func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
    let userInfo = response.notification.request.content.userInfo
    
    // Handle different actions
    switch response.actionIdentifier {
    case "view":
        print("User tapped 'View' action")
        // Navigate to relevant screen
    case "dismiss":
        print("User dismissed notification")
    default:
        print("Unknown action identifier")
    }
    
    completionHandler()
}