How to handle notification is opened #172

How do I know if the application is opened by clicking the notification when the application is closed?

FCM payload looks like below:

 "notification": {
      "title": "hello",
      "body": "test message",
      "click_action": "OPEN_ACTIVITY_1"
  },

This is using "click_action" on firebase. But we couldn't find this function on "azurenotificationhub". And I don't know how to do this.
As a result, I want to open the page I want when the notification is clicked while the application is closed.