要注册设备以进行推送通知，请使用 didFinishLaunchingWithOptions 方法将以下代码添加到 AppDelegate 文件中：

迅速

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
    // Override point for customization after application launch.
    if UIDevice.currentDevice().systemVersion.compare(v, options: .NumericSearch) == NSOrderedAscending { 
        // Register for Push Notitications, if running iOS < 8
        if application.respondsToSelector("registerUserNotificationSettings:") {
            let types:UIUserNotificationType = (.Alert | .Badge | .Sound)
            let settings:UIUserNotificationSettings = UIUserNotificationSettings(forTypes: types, categories: nil)

            application.registerUserNotificationSettings(settings)
            application.registerForRemoteNotifications()
        } else {      
            // Register for Push Notifications before iOS 8
            application.registerForRemoteNotificationTypes(.Alert | .Badge | .Sound)
        }
    } else {
        var center = UNUserNotificationCenter.currentNotificationCenter()
        center.delegate = self
        center.requestAuthorizationWithOptions((UNAuthorizationOptionSound | UNAuthorizationOptionAlert | UNAuthorizationOptionBadge)) {(granted: Bool, error: NSError) -> Void in
            if !error {
                UIApplication.sharedApplication().registerForRemoteNotifications()
                // required to get the app to do anything at all about push notifications
                print("Push registration success.")
            } else {
                print("Push registration FAILED")
                print("ERROR: \(error.localizedFailureReason!) - \(error.localizedDescription)")
                print("SUGGESTIONS: \(error.localizedRecoveryOptions) - \(error.localizedRecoverySuggestion!)")
            })
    }

    return true
}

Objective-C

#define SYSTEM_VERSION_LESS_THAN(v) ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] == NSOrderedAscending)

if( SYSTEM_VERSION_LESS_THAN( @"10.0" ) )
{
        if ([application respondsToSelector:@selector(isRegisteredForRemoteNotifications)])
    {
        // iOS 8 Notifications
        [application registerUserNotificationSettings:[UIUserNotificationSettings settingsForTypes:(UIUserNotificationTypeSound | UIUserNotificationTypeAlert | UIUserNotificationTypeBadge) categories:nil]];
        
        [application registerForRemoteNotifications];
    }
    else
    {
        // iOS < 8 Notifications
        [application registerForRemoteNotificationTypes:
         (UIRemoteNotificationTypeBadge | UIRemoteNotificationTypeAlert | UIRemoteNotificationTypeSound)];
    }

}
else
{
    UNUserNotificationCenter *center = [UNUserNotificationCenter currentNotificationCenter];
    center.delegate = self;
    [center requestAuthorizationWithOptions:(UNAuthorizationOptionSound | UNAuthorizationOptionAlert | UNAuthorizationOptionBadge) completionHandler:^(BOOL granted, NSError * _Nullable error)
     {
         if( !error )
         {
             [[UIApplication sharedApplication] registerForRemoteNotifications];  // required to get the app to do anything at all about push notifications
             NSLog( @"Push registration success." );
         }
         else
         {
             NSLog( @"Push registration FAILED" );
             NSLog( @"ERROR: %@ - %@", error.localizedFailureReason, error.localizedDescription );
             NSLog( @"SUGGESTIONS: %@ - %@", error.localizedRecoveryOptions, error.localizedRecoverySuggestion );  
         }  
     }];  
}

//to check if your App lunch from Push notification 
//---------------------------------------------------
    //Handel Push notification
    if (launchOptions != nil)
    {
        // Here app will open from pushnotification
        //RemoteNotification
        NSDictionary* dictionary1 = [launchOptions objectForKey:UIApplicationLaunchOptionsRemoteNotificationKey];
        //LocalNotification
        NSDictionary* dictionary2 = [launchOptions objectForKey:UIApplicationLaunchOptionsLocalNotificationKey];
        if (dictionary1 != nil)
        {
            //RemoteNotification Payload
            NSLog(@"Launched from push notification: %@", dictionary1);
            //here handle your push notification
        }
        if (dictionary2 != nil)
        {
            NSLog(@"Launched from dictionary2dictionary2dictionary2 notification: %@", dictionary2);
            double delayInSeconds = 7;
            dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
            dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
                // [self addMessageFromRemoteNotification:dictionary2 updateUI:NO];
            });
        }
        
     }
     else
         {}
    //------------------------------------------------

上面的代码将尝试与 APNs 服务器通信以获取设备令牌（前提是你在 iOS 配置文件中启用了 APN）。

一旦与 APNs 服务器建立可靠的连接，服务器就会为你提供设备令牌。

添加上面的代码后，将这些方法添加到 AppDelegate 类：

迅速

func application(application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: NSData) {
    print("DEVICE TOKEN = \(deviceToken)")
}

func application(application: UIApplication, didFailToRegisterForRemoteNotificationsWithError error: NSError) {
    print(error)
}

Objective-C

- (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken
{    
NSString * deviceTokenString = [[[[deviceToken description]
                     stringByReplacingOccurrencesOfString: @"<" withString: @""] 
                    stringByReplacingOccurrencesOfString: @">" withString: @""] 
                   stringByReplacingOccurrencesOfString: @" " withString: @""];

NSLog(@"The generated device token string is : %@",deviceTokenString);
}

- (void)application:(UIApplication*)application didFailToRegisterForRemoteNotificationsWithError:(NSError*)error
{
    NSLog(@"Failed to get token, error: %@", error.description);
}

根据注册成功或失败场景调用上述方法。

成功场景调用：

迅速

func application(application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: NSData) {
    print("DEVICE TOKEN = \(deviceToken)")
}

在 Swift3 中：

@objc(userNotificationCenter:willPresentNotification:withCompletionHandler:) @available(iOS 10.0, *)
func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void)
{
    //To show notifications in foreground.
   print("Userinfo2 \(notification.request.content.userInfo)")
}

Objective-C

- (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken
{
if(application.applicationState == UIApplicationStateInactive) { 
    NSLog(@"Inactive - the user has tapped in the notification when app was closed or in background");
    //do some tasks
    [self handelPushNotification:userInfo];
}
else if (application.applicationState == UIApplicationStateBackground) {
    NSLog(@"application Background - notification has arrived when app was in background");
    [self handelPushNotification:userInfo];
}
else {
    NSLog(@"application Active - notication has arrived while app was opened");
    //Show an in-app banner
    //do tasks
}
}

失败场景调用：

迅速

func application(application: UIApplication, didFailToRegisterForRemoteNotificationsWithError error: NSError) {
    print(error)
}

Objective-C

- (void)application:(UIApplication*)application didFailToRegisterForRemoteNotificationsWithError:(NSError*)error

注意

如果没有调用上述方法，则你的设备无法与 APN 服务器建立可靠的连接，这可能是因为 Internet 访问问题。