Try to Preview the navigation (not working)

app/src/main/java/io/element/android/x/MainActivity.kt

@@ -11,9 +11,10 @@ import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
-import androidx.lifecycle.Lifecycle
+import androidx.compose.ui.tooling.preview.Preview
 import com.ramcosta.composedestinations.DestinationsNavHost
 import com.ramcosta.composedestinations.rememberNavHostEngine
+import com.ramcosta.composedestinations.spec.Route
 import io.element.android.x.core.compose.OnLifecycleEvent
 import io.element.android.x.designsystem.ElementXTheme
 import io.element.android.x.destinations.OnBoardingScreenNavigationDestination
@@ -36,8 +37,6 @@ class MainActivity : ComponentActivity() {
 
 @Composable
 private fun MainScreen(viewModel: MainViewModel) {
-    val engine = rememberNavHostEngine()
-    val navController = engine.rememberNavController()
     val startRoute = runBlocking {
         if (!viewModel.isLoggedIn()) {
             OnBoardingScreenNavigationDestination
@@ -47,11 +46,7 @@ private fun MainScreen(viewModel: MainViewModel) {
         }
     }
 
-    DestinationsNavHost(
-        modifier = Modifier.background(MaterialTheme.colorScheme.background),
-        engine = engine,
-        navController = navController,
-        navGraph = NavGraphs.root,
+    MainContent(
         startRoute = startRoute
     )
 
@@ -59,3 +54,23 @@ private fun MainScreen(viewModel: MainViewModel) {
         Timber.v("OnLifecycleEvent: $event")
     }
 }
+
+@Composable
+private fun MainContent(startRoute: Route) {
+    val engine = rememberNavHostEngine()
+    val navController = engine.rememberNavController()
+
+    DestinationsNavHost(
+        modifier = Modifier.background(MaterialTheme.colorScheme.background),
+        engine = engine,
+        navController = navController,
+        navGraph = NavGraphs.root,
+        startRoute = startRoute
+    )
+}
+
+@Composable
+@Preview
+private fun MainContentPreview() {
+    MainContent(startRoute = OnBoardingScreenNavigationDestination)
+}