title: How to implement Firebase Messaging to Xamarin.Android application?
body: <p>I am making my Android application using Xamarin.Android.
  I want to implement push notifications, I am trying to do it with Firebase following this guide: <a href="https://docs.microsoft.com/en-us/xamarin/android/data-cloud/google-messaging/remote-notifications-with-fcm?tabs=windows" rel="nofollow noreferrer">https://docs.microsoft.com/en-us/xamarin/android/data-cloud/google-messaging/remote-notifications-with-fcm?tabs=windows</a>
  However this guide and others on the same topic seems to be outdated. When I create a new project in Firebase Console and click add to android application i see instruction for Android Studio, Unity and Web application. No instruction for Xamarin. When i try to follow instruction for Android Studio i can get google-services.json file but i cant follow part 3 and 4 (Adding android SDK and Testing connectivity) because they are for gradle development. 
  How use Firebase Cloud Messaging in Xamarin.Android application or Is there any other way to add push notifications for my application?</p>
  
  <p>Update:</p>
  
  <p>I downloaded new google-services.json file from Firebase Console -> Settings to my project, cleaned the solution, rebuild it and deleted app from device. When I test app on a device and click on Log Token Button the token in Log Output is empty, after that it gives me: 
  D/FirebaseInstanceId(14477): background sync failed: TIMEOUT, retry in 10s. 
  So now i cant get the Token, or maybe I cant refresh it. </p>
  
  <p>I checked the following:</p>
  
  <ul>
  <li>Package name of my project match the package name on Firebase app</li>
  <li>google-services.json Build Action is set to GoogleServicesJson</li>
  <li>Google Play Services is available on my device(Samsung SM-A500F Android 6.0 API 23), I also tested this on other devices and still not working</li>
  </ul>
  
  <p>I'm dealing with this problem a long time, if you need any other information, please ask me. </p>