You should get device token from Firebase and register the current user in backend side with the same token.
After that, you can send push notifications from your backend.
Put this code in AppDelegate class.
Call InitAPNS() from FinishedLaunching.
public override void RegisteredForRemoteNotifications(UIApplication application, NSData deviceToken)
{
//TODO: save token and register one in backend side
Settings.DeviceTokenFCM = InstanceId.SharedInstance.Token;
}
public override void DidReceiveRemoteNotification(UIApplication application, NSDictionary userInfo, Action<UIBackgroundFetchResult> completionHandler)
{
ShowPushMessage(userInfo);
}
private void ShowPushMessage(NSDictionary userInfo)
{
if (userInfo != null)
{
try
{
var apsDictionary = userInfo["aps"] as NSDictionary;
var alertDictionary = apsDictionary?["alert"] as NSDictionary;
var body = alertDictionary?["body"].ToString();
var title = alertDictionary?["title"].ToString();
var window = UIApplication.SharedApplication.KeyWindow;
var vc = window.RootViewController;
var alert = UIAlertController.Create(title, body, UIAlertControllerStyle.Alert);
alert.AddAction(UIAlertAction.Create("OK", UIAlertActionStyle.Cancel, null));
vc.PresentViewController(alert, animated: true, completionHandler: null);
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine(ex);
}
}
}
private void InitAPNS()
{
// Monitor token generation
InstanceId.Notifications.ObserveTokenRefresh(TokenRefreshNotification);
if (UIDevice.CurrentDevice.CheckSystemVersion(10, 0))
{
UNUserNotificationCenter.Current.RequestAuthorization(UNAuthorizationOptions.Alert | UNAuthorizationOptions.Sound | UNAuthorizationOptions.Sound, (granted, error) =>
{
if (granted)
{
InvokeOnMainThread(UIApplication.SharedApplication.RegisterForRemoteNotifications);
}
});
}
else if (UIDevice.CurrentDevice.CheckSystemVersion(8, 0))
{
var pushSettings = UIUserNotificationSettings.GetSettingsForTypes(
UIUserNotificationType.Alert | UIUserNotificationType.Badge | UIUserNotificationType.Sound,
new NSSet());
UIApplication.SharedApplication.RegisterUserNotificationSettings(pushSettings);
UIApplication.SharedApplication.RegisterForRemoteNotifications();
}
else
{
UIRemoteNotificationType notificationTypes = UIRemoteNotificationType.Alert | UIRemoteNotificationType.Badge | UIRemoteNotificationType.Sound;
UIApplication.SharedApplication.RegisterForRemoteNotificationTypes(notificationTypes);
}
Firebase.Core.App.Configure();
}
private void TokenRefreshNotification(object sender, NSNotificationEventArgs e)
{
ConnectToFCM();
}
private void ConnectToFCM()
{
var tokenFirebase = InstanceId.SharedInstance.Token;
////registation token in background thread
System.Threading.Tasks.Task.Run(() =>
{
if (!string.IsNullOrEmpty(tokenFirebase))
{
Firebase.CloudMessaging.Messaging.SharedInstance.SetApnsToken(tokenFirebase, ApnsTokenType.Production);
}
});
Messaging.SharedInstance.ShouldEstablishDirectChannel = true;
}