topics_fragment.kt

private lateinit var presenter: TopicsPresenter
	...
     override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        presenter = TopicsPresenter(dataRepository)
    }

	...
	
	override fun onResume() {
        super.onResume()
        //Notice presenter that view can be accessible
        presenter.onViewActive(this)	
	}
	
	 override fun onPause() {
        //Notice presenter that view cannot be accessible
        presenter.onViewInactive()
        super.onPause()
    }
}