Tidy up top level destination handling

Change-Id: I385b6f49ba37801e40bb90254abe96e2350d48e8

app/src/main/kotlin/com/google/samples/apps/nowinandroid/navigation/TopLevelDestination.kt

@@ -16,6 +16,7 @@
 
 package com.google.samples.apps.nowinandroid.navigation
 
+import androidx.annotation.StringRes
 import androidx.compose.ui.graphics.vector.ImageVector
 import com.google.samples.apps.nowinandroid.R
 import com.google.samples.apps.nowinandroid.core.designsystem.icon.NiaIcons
@@ -35,8 +36,8 @@ import com.google.samples.apps.nowinandroid.feature.search.R as searchR
 enum class TopLevelDestination(
     val selectedIcon: ImageVector,
     val unselectedIcon: ImageVector,
-    val iconTextId: Int,
-    val titleTextId: Int,
+    @StringRes val iconTextId: Int,
+    @StringRes val titleTextId: Int,
     val route: KClass<*>,
 ) {
     FOR_YOU(

app/src/main/kotlin/com/google/samples/apps/nowinandroid/ui/NiaApp.kt

@@ -73,6 +73,7 @@ import com.google.samples.apps.nowinandroid.core.designsystem.theme.LocalGradien
 import com.google.samples.apps.nowinandroid.feature.settings.SettingsDialog
 import com.google.samples.apps.nowinandroid.navigation.NiaNavHost
 import com.google.samples.apps.nowinandroid.navigation.TopLevelDestination
+import kotlin.reflect.KClass
 import com.google.samples.apps.nowinandroid.feature.settings.R as settingsR
 
 @OptIn(ExperimentalMaterial3AdaptiveApi::class)
@@ -151,7 +152,7 @@ internal fun NiaApp(
             appState.topLevelDestinations.forEach { destination ->
                 val hasUnread = unreadDestinations.contains(destination)
                 val selected = currentDestination
-                    .isTopLevelDestinationInHierarchy(destination)
+                    .isRouteInHierarchy(destination.route)
                 item(
                     selected = selected,
                     onClick = { appState.navigateToTopLevelDestination(destination) },
@@ -199,8 +200,10 @@ internal fun NiaApp(
             ) {
                 // Show the top app bar on top level destinations.
                 val destination = appState.currentTopLevelDestination
-                val shouldShowTopAppBar = destination != null
+                var shouldShowTopAppBar = false
+
                 if (destination != null) {
+                    shouldShowTopAppBar = true
                     NiaTopAppBar(
                         titleRes = destination.titleTextId,
                         navigationIcon = NiaIcons.Search,
@@ -267,7 +270,7 @@ private fun Modifier.notificationDot(): Modifier =
         }
     }
 
-private fun NavDestination?.isTopLevelDestinationInHierarchy(destination: TopLevelDestination) =
+private fun NavDestination?.isRouteInHierarchy(route: KClass<*>) =
     this?.hierarchy?.any {
-        it.hasRoute(destination.route)
+        it.hasRoute(route)
     } ?: false

app/src/main/kotlin/com/google/samples/apps/nowinandroid/ui/NiaAppState.kt

@@ -92,12 +92,9 @@ class NiaAppState(
 
     val currentTopLevelDestination: TopLevelDestination?
         @Composable get() {
-            with(currentDestination) {
-                if (this?.hasRoute<ForYouRoute>() == true) return FOR_YOU
-                if (this?.hasRoute<BookmarksRoute>() == true) return BOOKMARKS
-                if (this?.hasRoute<InterestsRoute>() == true) return INTERESTS
+            return TopLevelDestination.entries.firstOrNull { topLevelDestination ->
+                currentDestination?.hasRoute(route = topLevelDestination.route) ?: false
             }
-            return null
         }
 
     val isOffline = networkMonitor.isOnline

app/src/main/kotlin/com/google/samples/apps/nowinandroid/ui/interests2pane/Interests2PaneViewModel.kt

@@ -20,7 +20,6 @@ import androidx.lifecycle.SavedStateHandle
 import androidx.lifecycle.ViewModel
 import androidx.navigation.toRoute
 import com.google.samples.apps.nowinandroid.feature.interests.navigation.InterestsRoute
-import com.google.samples.apps.nowinandroid.feature.interests.navigation.TOPIC_ID_KEY
 import dagger.hilt.android.lifecycle.HiltViewModel
 import kotlinx.coroutines.flow.StateFlow
 import javax.inject.Inject