Create Singleton Object
object App { class User(val id: String, val name: String, val isAdmin: Boolean) var currentUser: User? get() = currentUserLiveData.value set(value) { currentUserLiveData.postValue(value) } val currentUserLiveData = MutableLiveData<User?>()}
When user sign in/login.
App.currentUser = App.User("5pSFOxspzl75hYZzjnut", "Desmond Lua", true)
When user sign off/logout.
App.currentUser = null
Observer changes in Activity/Fragment.
App.currentUserLiveData.observe(this, Observer { user -> // do something})