Starting app only if its not currently running

Question

I am sending push notification to users which when clicking on it opens the app.

My problem is that when the app is already open, clicking on the notification start

Answer 1

For those who use Xamarin.Android. The Xamarin version of David Wasser's answer is below:

        //Create notification
        var notificationManager = GetSystemService(Context.NotificationService) as NotificationManager;
        Intent uiIntent = PackageManager.GetLaunchIntentForPackage("com.company.app");

        //Create the notification
        var notification = new Notification(Android.Resource.Drawable.SymActionEmail, title);

        //Auto-cancel will remove the notification once the user touches it
        notification.Flags = NotificationFlags.AutoCancel;

        //Set the notification info
        //we use the pending intent, passing our ui intent over, which will get called
        //when the notification is tapped.
        notification.SetLatestEventInfo(this, title, desc, PendingIntent.GetActivity(this, 0, uiIntent, PendingIntentFlags.OneShot));

        //Show the notification
        notificationManager.Notify(0, notification);