UNUserNotificationCenter.current().getPendingNotificationRequests { (requests) in
    //遍历所有未推送的request
    for request in requests {
        print(request)
    }
}

UNUserNotificationCenter.current().getDeliveredNotifications { (notifications) in
    //遍历所有已推送的通知
    for notification in notifications {
        print(notification)
    }
}

//使用同样的请求标识符来设置一个新的通知
let requestIdentifier = "com.hangge.testNotification"
let request = UNNotificationRequest(identifier: requestIdentifier,
                                    content: content, trigger: trigger)
 
//将通知请求添加到发送中心
UNUserNotificationCenter.current().add(request) { error in
    if error == nil {
        print("Time Interval Notification scheduled: \(requestIdentifier)")
    }
}

//根据identifier来取消指定通知
let identifier = "com.hangge.testNotification"
UNUserNotificationCenter.current().removePendingNotificationRequests(withIdentifiers: [identifier])
 
//取消全部未发送通知
UNUserNotificationCenter.current().removeAllPendingNotificationRequests()

//根据identifier来删除指定通知
let identifier = "com.hangge.testNotification"
UNUserNotificationCenter.current().removeDeliveredNotifications(withIdentifiers: [identifier])
 
//删除全部已发送通知
UNUserNotificationCenter.current().removeAllDeliveredNotifications()

import UIKit
import UserNotifications
 
@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
     
    var window: UIWindow?
     
    let notificationHandler = NotificationHandler()
     
    func application(_ application: UIApplication, didFinishLaunchingWithOptions
        launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
        //请求通知权限
        UNUserNotificationCenter.current()
            .requestAuthorization(options: [.alert, .sound, .badge]) {
                (accepted, error) in
                if !accepted {
                    print("用户不允许消息通知。")
                }
        }
         
        //设置通知代理
        UNUserNotificationCenter.current().delegate = notificationHandler
         
        return true
    }
     
    func applicationWillResignActive(_ application: UIApplication) {
    }
     
    func applicationDidEnterBackground(_ application: UIApplication) {
    }
     
    func applicationWillEnterForeground(_ application: UIApplication) {
    }
     
    func applicationDidBecomeActive(_ application: UIApplication) {
    }
     
    func applicationWillTerminate(_ application: UIApplication) {
    }
}
 
class NotificationHandler: NSObject, UNUserNotificationCenterDelegate {
    //在应用内展示通知
    func userNotificationCenter(_ center: UNUserNotificationCenter,
                                willPresent notification: UNNotification,
                                withCompletionHandler completionHandler:
        @escaping (UNNotificationPresentationOptions) -> Void) {
        completionHandler([.alert, .sound])
         
        // 如果不想显示某个通知，可以直接用空 options 调用 completionHandler:
        // completionHandler([])
    }
}

import UIKit
import UserNotifications
 
class ViewController: UIViewController {
     
    override func viewDidLoad() {
        super.viewDidLoad()
         
        //设置推送内容
        let content = UNMutableNotificationContent()
        content.title = "hangge.com"
        content.body = "做最好的开发者知识平台"
        content.userInfo = ["userName": "hangge", "articleId": 10086]
         
        //设置通知触发器
        let trigger = UNTimeIntervalNotificationTrigger(timeInterval: 30, repeats: false)
         
        //设置请求标识符
        let requestIdentifier = "com.hangge.testNotification"
         
        //设置一个通知请求
        let request = UNNotificationRequest(identifier: requestIdentifier,
                                            content: content, trigger: trigger)
         
        //将通知请求添加到发送中心
        UNUserNotificationCenter.current().add(request) { error in
            if error == nil {
                print("Time Interval Notification scheduled: \(requestIdentifier)")
            }
        }
    }
     
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
    }
}

import UIKit
import UserNotifications
 
@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
     
    var window: UIWindow?
     
    let notificationHandler = NotificationHandler()
     
    func application(_ application: UIApplication, didFinishLaunchingWithOptions
        launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
        //请求通知权限
        UNUserNotificationCenter.current()
            .requestAuthorization(options: [.alert, .sound, .badge]) {
                (accepted, error) in
                if !accepted {
                    print("用户不允许消息通知。")
                }
        }
         
        //设置通知代理
        UNUserNotificationCenter.current().delegate = notificationHandler
         
        return true
    }
     
    func applicationWillResignActive(_ application: UIApplication) {
    }
     
    func applicationDidEnterBackground(_ application: UIApplication) {
    }
     
    func applicationWillEnterForeground(_ application: UIApplication) {
    }
     
    func applicationDidBecomeActive(_ application: UIApplication) {
    }
     
    func applicationWillTerminate(_ application: UIApplication) {
    }
}
 
class NotificationHandler: NSObject, UNUserNotificationCenterDelegate {
    //对通知进行响应（用户与通知进行交互时被调用）
    func userNotificationCenter(_ center: UNUserNotificationCenter,
                                didReceive response: UNNotificationResponse,
                                withCompletionHandler completionHandler:
        @escaping () -> Void) {
        print(response.notification.request.content.title)
        print(response.notification.request.content.body)
        //获取通知附加数据
        let userInfo = response.notification.request.content.userInfo
        print(userInfo)
        //完成了工作
        completionHandler()
    }
}