ViewController.swift

//
// Copyright (c) 2016 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//

import UIKit
import FirebaseMessaging

@objc(ViewController)
classViewController:UIViewController{
@IBOutletvarfcmTokenMessage:UILabel!
@IBOutletvarremoteFCMTokenMessage:UILabel!

overridefunc viewDidLoad(){
NotificationCenter.default.addObserver(
self,
 selector: #selector(displayFCMToken(notification:)),
 name:Notification.Name("FCMToken"),
 object:nil
)
}

@IBActionfunc handleLogTokenTouch(_ sender:UIButton){
 // [START log_fcm_reg_token]
lettoken=Messaging.messaging().fcmToken
print("FCM token: \(token ??"")")
 // [END log_fcm_reg_token]
 fcmTokenMessage.text ="Logged FCM token: \(token ??"")"

 // [START log_iid_reg_token]
Messaging.messaging().token{ token, error in
iflet error = error {
print("Error fetching remote FCM registration token: \(error)")
}elseiflet token = token {
print("Remote instance ID token: \(token)")
self.remoteFCMTokenMessage.text ="Remote FCM registration token: \(token)"
}
}
 // [END log_iid_reg_token]
}

@IBActionfunc handleSubscribeTouch(_ sender:UIButton){
 // [START subscribe_topic]
Messaging.messaging().subscribe(toTopic:"weather"){ error in
print("Subscribed to weather topic")
}
 // [END subscribe_topic]
}

@objcfunc displayFCMToken(notification:NSNotification){
guardlet userInfo = notification.userInfo else{return}
iflet fcmToken =userInfo["token"]as?String{
 fcmTokenMessage.text ="Received FCM token: \(fcmToken)"
}
}
}