Push remote notification - swift

Question

I need create in my app a code that receive a remote information and push it to user when app is on background, I read on web that I need to use didReceiveRemoteNotification on appDelegate, to use remote push notication. I read something about and I need keys and certificates, I do not understand how to use didReceiveRemoteNotification
I need to learn about to push remote notification and how to use. I would like a tutorial or example how create it using swift 2.3.

Answer 1

I used this link and I found it the most helpful
http://www.appcoda.com/push-notification-ios/
I used this app for testing
https://itunes.apple.com/us/app/easy-apns-provider-push-notification/id989622350?mt=12
This is the code I have in my AppDelegate
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
registerForPushNotifications(application)
print(UIDevice.currentDevice().identifierForVendor!.UUIDString)
return true
}
func registerForPushNotifications(application: UIApplication) {
let notificationSettings = UIUserNotificationSettings(
forTypes: [.Badge, .Sound, .Alert], categories: nil)
application.registerUserNotificationSettings(notificationSettings)
}
func application(application: UIApplication, didRegisterUserNotificationSettings notificationSettings: UIUserNotificationSettings) {
if notificationSettings.types != .None {
application.registerForRemoteNotifications()
}
}
func application(application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: NSData) {
let tokenChars = UnsafePointer<CChar>(deviceToken.bytes)
var tokenString = ""
for i in 0..<deviceToken.length {
tokenString += String(format: "%02.2hhx", arguments: [tokenChars[i]])
}
print("Device Token:", tokenString)
}
func application(application: UIApplication, didFailToRegisterForRemoteNotificationsWithError error: NSError) {
print("Failed to register:", error)
}