Jetpack Compose 탐색 생성 및 인수 제출

sealed class Screen(val route: String) {
    object HomeScreen : Screen(route ="home")
    object DetailScreen : Screen(route = "detail")

    // To send multiple arguments
    fun withArgs(vararg args: String): String {
        return buildString {
            append(route)
            args.forEach { arg ->
                append("/$arg")
            }
        }
    }
}

@Composable
fun HomeScreen(navController: NavController) {
    var name by remember { mutableStateOf("") }
    var surname by remember { mutableStateOf("") }
    val context = LocalContext.current

    Scaffold(
        topBar = {
            TopAppBar(title = { Text(text = "Home Screen") })
        }
    ) {
        Box(modifier = Modifier.fillMaxSize()) {
            Column(
                modifier = Modifier
                    .fillMaxSize()
                    .padding(16.dp),
                verticalArrangement = Arrangement.Center,
                horizontalAlignment = Alignment.CenterHorizontally
            ) {
                OutlinedTextField(
                    value = name,
                    label = { Text(text = "Name") },
                    onValueChange = { name = it },
                    modifier = Modifier.padding(vertical = 16.dp)
                )
                OutlinedTextField(
                    value = surname,
                    label = { Text(text = "Surname") },
                    onValueChange = { surname = it },
                    modifier = Modifier.padding(vertical = 16.dp)
                )
                Button(onClick = {
                   // Check if textfields are null
                    if (name.isNotEmpty()) {  
//With route arguments for Detail Screen.                  navController.navigate(Screen.DetailScreen.withArgs(name, surname))
                    } else {
                        Toast.makeText(context, "Fill in the required fields.", Toast.LENGTH_SHORT)
                            .show()
                    }
                }) {
                    Text(text = "Send Detail Screen")
                }
            }
        }
    }
}

@Composable
fun DetailScreen(name: String?, surname: String?, navController: NavController) {

    Scaffold(
        topBar = {
            TopAppBar(title = { Text(text = "Detail Screen") }, navigationIcon = {
                IconButton(
                    onClick = {
                        navController.popBackStack()
                    }) {
                    Icon(imageVector = Icons.Rounded.ArrowBack, contentDescription = "posStackBack")
                }
            })
        }
    ) {
        Box(modifier = Modifier.fillMaxSize()) {
            Column(
                modifier = Modifier
                    .fillMaxSize()
                    .padding(16.dp),
                verticalArrangement = Arrangement.Center,
                horizontalAlignment = Alignment.CenterHorizontally
            ) {
                Text(text = "Hello $name $surname", fontWeight = FontWeight.Bold)
            }
        }
    }
}

@Composable
fun Navigation() {
    val navController = rememberNavController()
    NavHost(navController = navController, startDestination = Screen.HomeScreen.route) {
        composable(route = Screen.HomeScreen.route) {
            HomeScreen(navController = navController)
        }
        composable(route = Screen.DetailScreen.route + "/{name}/{surname}",
            arguments = listOf(
                navArgument("name") {
                    type = NavType.StringType
                    nullable = false
                },
                navArgument("surname") {
                    type = NavType.StringType
                    nullable = false
                }
            )
        ) { entry ->
            DetailScreen(
                name = entry.arguments?.getString("name"),
                surname = entry.arguments?.getString("surname"),
                navController = navController
            )
        }
    }
}

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            DevToTheme {
                Navigation()
            }
        }
    }
}