Scaffold.kt

@Composable
fun AppScaffold() {
    val viewModel: MainViewModel = viewModel()
    val navController = rememberNavController()
    val scaffoldState = rememberScaffoldState()
    val scope = rememberCoroutineScope()
    val currentScreen by viewModel.currentScreen.observeAsState()

    var topBar : @Composable () -> Unit = {
        TopBar(
            title = currentScreen!!.title,
            buttonIcon = Icons.Filled.Menu,
            onButtonClicked = {
                scope.launch {
                    scaffoldState.drawerState.open()
                }
            }
        )
    }
    if (currentScreen == Screens.DrawerScreens.Help) {
        topBar = {
            TopBar(
                title = Screens.DrawerScreens.Help.title,
                buttonIcon = Icons.Filled.ArrowBack,
                onButtonClicked = {
                    navController.popBackStack()
                }
            )
        }
    }

    val bottomBar: @Composable () -> Unit = {
        if (currentScreen == Screens.DrawerScreens.Home || currentScreen is Screens.HomeScreens) {
            BottomBar(
                navController = navController,
                screens = screensInHomeFromBottomNav
            )
        }
    }

    Scaffold(
        topBar = {
            topBar()
        },
        bottomBar = {
            bottomBar()
        },
        scaffoldState = scaffoldState,
        drawerContent = {
            Drawer { screen ->
                scope.launch {
                    scaffoldState.drawerState.close()
                }
                navController.navigate(screen.route) {
                    popUpTo = navController.graph.startDestination
                    launchSingleTop = true
                }
            }
        },
        drawerGesturesEnabled = scaffoldState.drawerState.isOpen,
    ) { innerPadding ->
        NavigationHost(navController = navController, viewModel = viewModel)
    }
}