如上所述，您应该使用UserNotification.framework来实现这一点。但出于我的目的，我必须在app中显示它，我想要iOS 11风格，所以我创建了一个小助手视图，可能对某些人有用。

GitHub iOS 11推送通知视图。

如果应用程序在前台运行，iOS不会显示通知横幅/警报。这是故意的。你必须编写一些代码来处理应用程序在前台接收通知的情况。您应该以最合适的方式显示通知(例如，向UITabBar图标添加徽章号，模拟notification Center横幅等)。

用于swift 5解析推送通知字典

    func application(_ application: UIApplication, didReceiveRemoteNotification data: [AnyHashable : Any]) {
            if application.applicationState == .active {
                if let aps1 = data["aps"] as? NSDictionary {
                    if let dict = aps1["alert"] as? NSDictionary {
                        if let strTitle = dict["title"] as? String , let strBody = dict["body"] as? String {
                            if let topVC = UIApplication.getTopViewController() {
                                //Apply your own logic as per requirement
                                print("strTitle ::\(strTitle) , strBody :: \(strBody)")
                            }
                        }
                    }
                }
            }
        }

获取topBanner所在的top viewController

extension UIApplication {

    class func getTopViewController(base: UIViewController? = UIApplication.shared.keyWindow?.rootViewController) -> UIViewController? {

        if let nav = base as? UINavigationController {
            return getTopViewController(base: nav.visibleViewController)

        } else if let tab = base as? UITabBarController, let selected = tab.selectedViewController {
            return getTopViewController(base: selected)

        } else if let presented = base?.presentedViewController {
            return getTopViewController(base: presented)
        }
        return base
    }
}

Xcode 10 Swift 4.2

当你的应用程序在前台时，显示推送通知

步骤1:在AppDelegate类中添加delegate UNUserNotificationCenterDelegate。

class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationCenterDelegate {

步骤2:设置UNUserNotificationCenter委托

let notificationCenter = UNUserNotificationCenter.current()
notificationCenter.delegate = self

第三步:这一步将允许你的应用程序显示推送通知，即使你的应用程序在前台

func userNotificationCenter(_ center: UNUserNotificationCenter,
                                willPresent notification: UNNotification,
                                withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
        completionHandler([.alert, .sound])

    }

步骤4:该步骤是可选的。检查你的应用程序是否在前台，如果在前台，然后显示本地推送通知。

func application(_ application: UIApplication,didReceiveRemoteNotification userInfo: [AnyHashable: Any],fetchCompletionHandler completionHandler:@escaping (UIBackgroundFetchResult) -> Void) {

        let state : UIApplicationState = application.applicationState
        if (state == .inactive || state == .background) {
            // go to screen relevant to Notification content
            print("background")
        } else {
            // App is in UIApplicationStateActive (running in foreground)
            print("foreground")
            showLocalNotification()
        }
    }

本地通知功能-

fileprivate func showLocalNotification() {

        //creating the notification content
        let content = UNMutableNotificationContent()

        //adding title, subtitle, body and badge
        content.title = "App Update"
        //content.subtitle = "local notification"
        content.body = "New version of app update is available."
        //content.badge = 1
        content.sound = UNNotificationSound.default()

        //getting the notification trigger
        //it will be called after 5 seconds
        let trigger = UNTimeIntervalNotificationTrigger(timeInterval: 1, repeats: false)

        //getting the notification request
        let request = UNNotificationRequest(identifier: "SimplifiedIOSNotification", content: content, trigger: trigger)

        //adding the notification to notification center
        notificationCenter.add(request, withCompletionHandler: nil)
    }

正如@Danial Martine所说，iOS不会显示通知横幅/提醒。这是故意的。但如果真要这么做，还有一个办法。我也用同样的方法做到了这一点。

1.从parse FrameWork下载解析框架

2.导入# Import <Parse/Parse.h> .h

3.将以下代码添加到您的didReceiveRemoteNotification方法

 - (void)application:(UIApplication *)application
didReceiveRemoteNotification:(NSDictionary *)userInfo
{
    [PFPush handlePush:userInfo];
}

PFPush会注意如何处理远程通知。如果App在前台，这显示警报，否则它显示在顶部的通知。

下面的代码将为您工作:

- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo  {
    application.applicationIconBadgeNumber = 0;             
    //self.textView.text = [userInfo description];
    // We can determine whether an application is launched as a result of the user tapping the action
    // button or whether the notification was delivered to the already-running application by examining
    // the application state.

    if (application.applicationState == UIApplicationStateActive) {                
        // Nothing to do if applicationState is Inactive, the iOS already displayed an alert view.                
        UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"Did receive a Remote Notification" message:[NSString stringWithFormat:@"Your App name received this notification while it was running:\n%@",[[userInfo objectForKey:@"aps"] objectForKey:@"alert"]]delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
        [alertView show];          
    }    
}