FCM notification not received when app is terminated

Hi @JarvanZhang It never was in any restrictions in the settings however, I've found out that if you run the application in a debug mode in Visual studio on a physical device through USB-debugging, and your notifications are working fine if you then close the app and/or terminate it by removing it from background processes, therefore, stopping the debugging session in VS, and also terminating the Firebase service in background. This causes that no notifications are being received since the service is not running. What I had to do is run the app on my phone or emulator manually without starting a debug session in Visual studio, then close it down or terminate it from background processes, and only then you could receive notifications cause you actually started the service once again with the app but this time since it was not a debug session in VS the service didn't get terminated with your app, meaning that notifications could again be received even without the app running in Background.

Yet I'm still unable to find a way to customize the look of the local notification or the Intent, also my device is now vibrating but only if the phone is in vibrate mode only. How can I make the app to make a sound and vibrate if the sound is enabled on the phone? Because now when sound is enabled only sound is made, in vibrate-only mode on a phone it only vibrates. If you know what I mean...

@JarvanZhang Also when creating an Intent like a local notification where do I set the action that is fired when the Intent is tapped? Like instead of taking me to the main screen of the app I guess it's the typeof(MainActivity). If I would like to open a specific view in the app but have as root the main screen...?

What framework do you test on? Since Android 8.0, sending notification requires a channel and please use NotificationCompat.Builder instead.

void sendNotification()
{
 var notificationManager = (NotificationManager)GetSystemService(NotificationService);
 if (Build.VERSION.SdkInt > BuildVersionCodes.O)
 {
 Intent intent = new Intent(this, typeof(TestActivity));
 PendingIntent pendingIntent = PendingIntent.GetActivity(this, 5, intent, PendingIntentFlags.Immutable);

 NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this, "CHANNEL_ID")
 .SetContentTitle("Alarm")
 .SetContentText("notofication message")
 .SetSmallIcon(Resource.Drawable.abc_ab_share_pack_mtrl_alpha)
 .SetAutoCancel(true)
 .SetContentIntent(pendingIntent);

 var chan = new NotificationChannel("CHANNEL_ID", GetString(Resource.String.abc_action_bar_home_description), NotificationImportance.Default);
 chan.LightColor = Android.Graphics.Color.Green;
 chan.LockscreenVisibility = NotificationVisibility.Private;

 chan.EnableVibration(true);
 chan.SetSound(...);

 notificationManager.CreateNotificationChannel(chan);
 notificationManager.Notify(1001, notificationBuilder.Build());
 }
}

And with the channel, you could enable the vibration and set a sound.

@JarvanZhang Thanks for the tip with the channel I had that setup already. The problem is that even though I have set defaults of the local notification to .SetDefaults(DefaultVibrate | DefaultSound) yet the phone only makes a sound when sound is enabled and when in VIBRATE-ONLY mode the phone only vibrates. I would like the phone to vibrate and make a sound at the same instance when sound is enabled on the device. I don't know if you understand but no matter what I try what vibrate patterns I set on the channel and notification the device doesn't want to vibrate when sound is enabled on the device, in that case, it ONLY makes a sound. I even tried using .SetDefaults((int)NotificationDefaults.All) the light and sound is working at the same time but it just doesn't want to vibrate.

Also, my other question is how can I handle the click on the intent and open a specific View in my app? Let's say I click on a notification and it would open up the app and inside it, it would navigate to NotificationsList which is a content page... But It should do so in a Navigation Stack so that when the back button is pressed you get to the Root page of the App.

@JarvanZhang
Nevermind the vibration part I solved that by enabling vibration in the channel, setting the sound of the channel to

channel.SetSound( 
RingtoneManager.GetDefaultUri(RingtoneType.Notification), 
new AudioAttributes.Builder().SetUsage(AudioUsageKind.Notification).Build()); 

and then I had to set the pattern of the vibration in the builder like so

.SetVibrate(new long[] { 300, 0, 300 }) 
.SetPriority((int)NotificationPriority.Max) 
.SetDefaults((int)NotificationDefaults.All) 

Now it works as intended.

However, the second question of mine remains about navigating to a certain content page after the notification is tapped, because I know I can handle the Intent tapped in MainActivity like so

protected override void OnNewIntent(Intent intent) 
{ 
 base.OnNewIntent(intent); 
 var type = (IntentTypes)intent.GetIntExtra("type", 1); 
 //if(type == IntentTypes.Notification) 
 //Open NotificationList View 
} 

But first I have to load the App itself right like this LoadApplication(new App()); or is that initialized beforehand in the OnCreate() method of MainActivity? If so, how can I navigate to a specific content page from MainActivity if the app is loaded?

Try to store a value to the intent when sending a notification.

Intent intent = new Intent(this, typeof(MainActivity));
intent.PutExtra("the_key", "the_value");

PendingIntent pendingIntent = PendingIntent.GetActivity(context, 5, intent, PendingIntentFlags.Immutable);

Then override the OnNewIntent of MainActivity to perform the navigation.

protected override void OnNewIntent(Intent intent)
{
 base.OnNewIntent(intent);

 if (intent.HasExtra("the_key") && intent.GetStringExtra("the_key") == "the_value")
 {
 App.Current.MainPage.Navigation.PushAsync(new TestPage());
 }
}

@JarvanZhang Thanks I tried that and it worked but only if the app was running in the background or foreground. However, if the app is closed or not running in the background nor foreground the Intent only starts the MainActivity which loads up the app, but it doesn't redirect me further. Also instead of MainActivity, I have to invoke SplashScreen activity and therefore the Intent has to be handled there is there a way to start the SplashScreen by the Intent but handle the intent in MainActivity after the App is loaded?

@JarvanZhang So now I got to a point where I can actually pass the Notification Intent to MainActivity from SplashScreen like so

public class SplashScreenActivity : Activity 
 { 
 
 public static readonly string TAG = "X:" + typeof(SplashScreenActivity).Name; 
 
 public override void OnCreate(Bundle savedInstanceState, PersistableBundle persistanteState) 
 { 
 base.OnCreate(savedInstanceState, persistanteState); 
 } 
 
 protected override void OnResume() 
 { 
 base.OnResume(); 
 var startupAction = new Task(StartupScreen); 
 startupAction.Start(); 
 } 
 
 public override void OnBackPressed() { } 
 
 private void StartupScreen() 
 { 
 var mainIntent = new Intent(Application.Context, typeof(MainActivity)); 
 
 if (Intent.Extras != null) 
 { 
 mainIntent.PutExtras(Intent.Extras); 
 } 
 mainIntent.SetFlags(ActivityFlags.SingleTop); 
 
 StartActivity(mainIntent); 
 } 
 } 

And then handle it in MainActivity like so

protected override void OnResume() 
{ 
 base.OnResume(); 
 OnNewIntent(Intent); 
 } 

And it kinda works but the problem is that it Navigates to where it is supposed to but I can't navigate out of the page backwards like if it was a root of Navigation even though it shouldn't.