navigator-example-1.kt

// 1. Initialize Navigator in Activity or Fragment

class MainActivity : ComponentActivity() {
  override fun onCreate(savedInstanceState: Bundle?) {
    ...
    val navigator = ComposeNavigator.with(this, savedInstanceState).initialize()
    setContent {
      ...
      MainScreen(navigator) // <-- Line: 34
    }
  }
}

// 2. Define Routes (destination)

sealed class MainRoute : Route {
  @Immutable @Parcelize
  data class First(val data: String) : MainRoute()
  @Immutable @Parcelize
  data class Second(private val noArg: String = "") : MainRoute() // no arg route
  
  companion object Key : Route.Key<MainRoute> // <-- Unique key for the root
}

@Composable // associated with MainRoute.First
fun FirstScreen(data: String, changed: (screen: Route) -> Unit) {...}

@Composable // associated with MainRoute.Second
fun SecondScreen() {...}

// 3. Setup Navigation

@Composable
fun MainScreen(navigator: ComposeNavigator) {
  // remember instance of controller, this will help you to manage navigation
  // for type MainRoute
  val controller = rememberNavController<MainRoute>()
  
  navigator.Setup(key = MainRoute.key, initial = MainRoute.First("Hello world"), controller = controller) { dest ->
    val goToSecond: () -> Unit = { value ->
      controller.navigateTo(MainRoute.Second()) // <-- Navigate to Second Route
    }
    when (dest) {
      is MainRoute.First -> FirstScreen(dest.data, goToSecond)
      is MainRoute.Second -> SecondScreen()
    }
  }
}