foonfyrick

onView(withId(R.id.menu_item_add)).check(
            matches(
                allOf(
                    isEnabled(),
                    isClickable()
                )
            )
        ).perform(
            object : ViewAction {
                override fun getDescription(): String {
                    return "click add button"
                }

                override fun getConstraints(): Matcher<View> {
                    return isEnabled()
                }

                override fun perform(uiController: UiController?, view: View?) {
                    view?.performClick()
                }
            }
        )

//MainActivity
 private lateinit var navController:NavController
 override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        navController=Navigation.findNavController(this,R.id.fragment)
        NavigationUI.setupActionBarWithNavController(this,navController)
    }

    override fun onSupportNavigateUp(): Boolean {
        return navController.navigateUp()
    }