Add type-safe navigation

app/build.gradle.kts

@@ -25,6 +25,7 @@ plugins {
     id("com.google.android.gms.oss-licenses-plugin")
     alias(libs.plugins.baselineprofile)
     alias(libs.plugins.roborazzi)
+    alias(libs.plugins.kotlin.serialization)
 }
 
 android {
@@ -103,6 +104,7 @@ dependencies {
     implementation(libs.androidx.window.core)
     implementation(libs.kotlinx.coroutines.guava)
     implementation(libs.coil.kt)
+    implementation(libs.kotlinx.serialization.json)
 
     ksp(libs.hilt.compiler)
 

app/dependencies/prodReleaseRuntimeClasspath.txt

@@ -2,25 +2,25 @@ androidx.activity:activity-compose:1.8.2
 androidx.activity:activity-ktx:1.8.2
 androidx.activity:activity:1.8.2
 androidx.annotation:annotation-experimental:1.4.1
-androidx.annotation:annotation-jvm:1.8.0
-androidx.annotation:annotation:1.8.0
+androidx.annotation:annotation-jvm:1.8.1
+androidx.annotation:annotation:1.8.1
 androidx.appcompat:appcompat-resources:1.7.0
 androidx.appcompat:appcompat:1.7.0
 androidx.arch.core:core-common:2.2.0
 androidx.arch.core:core-runtime:2.2.0
 androidx.autofill:autofill:1.0.0
 androidx.browser:browser:1.8.0
-androidx.collection:collection-jvm:1.4.0
-androidx.collection:collection-ktx:1.4.0
-androidx.collection:collection:1.4.0
-androidx.compose.animation:animation-android:1.7.0-rc01
-androidx.compose.animation:animation-core-android:1.7.0-rc01
-androidx.compose.animation:animation-core:1.7.0-rc01
-androidx.compose.animation:animation:1.7.0-rc01
-androidx.compose.foundation:foundation-android:1.7.0-rc01
-androidx.compose.foundation:foundation-layout-android:1.7.0-rc01
-androidx.compose.foundation:foundation-layout:1.7.0-rc01
-androidx.compose.foundation:foundation:1.7.0-rc01
+androidx.collection:collection-jvm:1.4.2
+androidx.collection:collection-ktx:1.4.2
+androidx.collection:collection:1.4.2
+androidx.compose.animation:animation-android:1.7.0
+androidx.compose.animation:animation-core-android:1.7.0
+androidx.compose.animation:animation-core:1.7.0
+androidx.compose.animation:animation:1.7.0
+androidx.compose.foundation:foundation-android:1.7.0
+androidx.compose.foundation:foundation-layout-android:1.7.0
+androidx.compose.foundation:foundation-layout:1.7.0
+androidx.compose.foundation:foundation:1.7.0
 androidx.compose.material3.adaptive:adaptive-android:1.0.0-rc01
 androidx.compose.material3.adaptive:adaptive-layout-android:1.0.0-rc01
 androidx.compose.material3.adaptive:adaptive-layout:1.0.0-rc01
@@ -39,25 +39,25 @@ androidx.compose.material:material-icons-extended-android:1.6.3
 androidx.compose.material:material-icons-extended:1.6.3
 androidx.compose.material:material-ripple-android:1.7.0-rc01
 androidx.compose.material:material-ripple:1.7.0-rc01
-androidx.compose.runtime:runtime-android:1.7.0-rc01
-androidx.compose.runtime:runtime-saveable-android:1.7.0-rc01
-androidx.compose.runtime:runtime-saveable:1.7.0-rc01
+androidx.compose.runtime:runtime-android:1.7.0
+androidx.compose.runtime:runtime-saveable-android:1.7.0
+androidx.compose.runtime:runtime-saveable:1.7.0
 androidx.compose.runtime:runtime-tracing:1.0.0-beta01
-androidx.compose.runtime:runtime:1.7.0-rc01
-androidx.compose.ui:ui-android:1.7.0-rc01
-androidx.compose.ui:ui-geometry-android:1.7.0-rc01
-androidx.compose.ui:ui-geometry:1.7.0-rc01
-androidx.compose.ui:ui-graphics-android:1.7.0-rc01
-androidx.compose.ui:ui-graphics:1.7.0-rc01
-androidx.compose.ui:ui-text-android:1.7.0-rc01
-androidx.compose.ui:ui-text:1.7.0-rc01
-androidx.compose.ui:ui-tooling-preview-android:1.7.0-rc01
-androidx.compose.ui:ui-tooling-preview:1.7.0-rc01
-androidx.compose.ui:ui-unit-android:1.7.0-rc01
-androidx.compose.ui:ui-unit:1.7.0-rc01
-androidx.compose.ui:ui-util-android:1.7.0-rc01
-androidx.compose.ui:ui-util:1.7.0-rc01
-androidx.compose.ui:ui:1.7.0-rc01
+androidx.compose.runtime:runtime:1.7.0
+androidx.compose.ui:ui-android:1.7.0
+androidx.compose.ui:ui-geometry-android:1.7.0
+androidx.compose.ui:ui-geometry:1.7.0
+androidx.compose.ui:ui-graphics-android:1.7.0
+androidx.compose.ui:ui-graphics:1.7.0
+androidx.compose.ui:ui-text-android:1.7.0
+androidx.compose.ui:ui-text:1.7.0
+androidx.compose.ui:ui-tooling-preview-android:1.7.0
+androidx.compose.ui:ui-tooling-preview:1.7.0
+androidx.compose.ui:ui-unit-android:1.7.0
+androidx.compose.ui:ui-unit:1.7.0
+androidx.compose.ui:ui-util-android:1.7.0
+androidx.compose.ui:ui-util:1.7.0
+androidx.compose.ui:ui:1.7.0
 androidx.compose:compose-bom:2024.02.02
 androidx.concurrent:concurrent-futures:1.1.0
 androidx.core:core-ktx:1.13.1
@@ -106,11 +106,11 @@ androidx.lifecycle:lifecycle-viewmodel:2.8.3
 androidx.loader:loader:1.0.0
 androidx.localbroadcastmanager:localbroadcastmanager:1.0.0
 androidx.metrics:metrics-performance:1.0.0-alpha04
-androidx.navigation:navigation-common-ktx:2.8.0-beta06
-androidx.navigation:navigation-common:2.8.0-beta06
-androidx.navigation:navigation-compose:2.8.0-beta06
-androidx.navigation:navigation-runtime-ktx:2.8.0-beta06
-androidx.navigation:navigation-runtime:2.8.0-beta06
+androidx.navigation:navigation-common-ktx:2.8.0
+androidx.navigation:navigation-common:2.8.0
+androidx.navigation:navigation-compose:2.8.0
+androidx.navigation:navigation-runtime-ktx:2.8.0
+androidx.navigation:navigation-runtime:2.8.0
 androidx.print:print:1.0.0
 androidx.privacysandbox.ads:ads-adservices-java:1.0.0-beta05
 androidx.privacysandbox.ads:ads-adservices:1.0.0-beta05

app/src/main/AndroidManifest.xml

@@ -47,9 +47,13 @@
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
             <intent-filter>
-                <data
-                    android:scheme="https"
-                    android:host="www.nowinandroid.apps.samples.google.com" />
+                <action android:name="android.intent.action.VIEW" />
+
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+
+                <data android:scheme="https" />
+                <data android:host="www.nowinandroid.apps.samples.google.com" />
             </intent-filter>
         </activity>
 

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

@@ -20,7 +20,7 @@ import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
 import androidx.navigation.compose.NavHost
 import com.google.samples.apps.nowinandroid.feature.bookmarks.navigation.bookmarksScreen
-import com.google.samples.apps.nowinandroid.feature.foryou.navigation.FOR_YOU_ROUTE
+import com.google.samples.apps.nowinandroid.feature.foryou.navigation.ForYouRoute
 import com.google.samples.apps.nowinandroid.feature.foryou.navigation.forYouScreen
 import com.google.samples.apps.nowinandroid.feature.interests.navigation.navigateToInterests
 import com.google.samples.apps.nowinandroid.feature.search.navigation.searchScreen
@@ -40,12 +40,11 @@ fun NiaNavHost(
     appState: NiaAppState,
     onShowSnackbar: suspend (String, String?) -> Boolean,
     modifier: Modifier = Modifier,
-    startDestination: String = FOR_YOU_ROUTE,
 ) {
     val navController = appState.navController
     NavHost(
         navController = navController,
-        startDestination = startDestination,
+        startDestination = ForYouRoute,
         modifier = modifier,
     ) {
         forYouScreen(onTopicClick = navController::navigateToInterests)

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

@@ -16,9 +16,14 @@
 
 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
+import com.google.samples.apps.nowinandroid.feature.bookmarks.navigation.BookmarksRoute
+import com.google.samples.apps.nowinandroid.feature.foryou.navigation.ForYouRoute
+import com.google.samples.apps.nowinandroid.feature.interests.navigation.InterestsRoute
+import kotlin.reflect.KClass
 import com.google.samples.apps.nowinandroid.feature.bookmarks.R as bookmarksR
 import com.google.samples.apps.nowinandroid.feature.foryou.R as forYouR
 import com.google.samples.apps.nowinandroid.feature.search.R as searchR
@@ -31,25 +36,29 @@ 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(
         selectedIcon = NiaIcons.Upcoming,
         unselectedIcon = NiaIcons.UpcomingBorder,
         iconTextId = forYouR.string.feature_foryou_title,
         titleTextId = R.string.app_name,
+        route = ForYouRoute::class,
     ),
     BOOKMARKS(
         selectedIcon = NiaIcons.Bookmarks,
         unselectedIcon = NiaIcons.BookmarksBorder,
         iconTextId = bookmarksR.string.feature_bookmarks_title,
         titleTextId = bookmarksR.string.feature_bookmarks_title,
+        route = BookmarksRoute::class,
     ),
     INTERESTS(
         selectedIcon = NiaIcons.Grid3x3,
         unselectedIcon = NiaIcons.Grid3x3,
         iconTextId = searchR.string.feature_search_interests,
         titleTextId = searchR.string.feature_search_interests,
+        route = InterestsRoute::class,
     ),
 }

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

@@ -60,6 +60,7 @@ import androidx.compose.ui.semantics.testTagsAsResourceId
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import androidx.navigation.NavDestination
+import androidx.navigation.NavDestination.Companion.hasRoute
 import androidx.navigation.NavDestination.Companion.hierarchy
 import com.google.samples.apps.nowinandroid.R
 import com.google.samples.apps.nowinandroid.core.designsystem.component.NiaBackground
@@ -72,6 +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)
@@ -150,7 +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) },
@@ -198,8 +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,
@@ -266,7 +270,7 @@ private fun Modifier.notificationDot(): Modifier =
         }
     }
 
-private fun NavDestination?.isTopLevelDestinationInHierarchy(destination: TopLevelDestination) =
+private fun NavDestination?.isRouteInHierarchy(route: KClass<*>) =
     this?.hierarchy?.any {
-        it.route?.contains(destination.name, true) ?: false
+        it.hasRoute(route)
     } ?: false

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

@@ -22,6 +22,7 @@ import androidx.compose.runtime.remember
 import androidx.compose.runtime.rememberCoroutineScope
 import androidx.navigation.NavController
 import androidx.navigation.NavDestination
+import androidx.navigation.NavDestination.Companion.hasRoute
 import androidx.navigation.NavGraph.Companion.findStartDestination
 import androidx.navigation.NavHostController
 import androidx.navigation.compose.currentBackStackEntryAsState
@@ -32,11 +33,8 @@ import com.google.samples.apps.nowinandroid.core.data.repository.UserNewsResourc
 import com.google.samples.apps.nowinandroid.core.data.util.NetworkMonitor
 import com.google.samples.apps.nowinandroid.core.data.util.TimeZoneMonitor
 import com.google.samples.apps.nowinandroid.core.ui.TrackDisposableJank
-import com.google.samples.apps.nowinandroid.feature.bookmarks.navigation.BOOKMARKS_ROUTE
 import com.google.samples.apps.nowinandroid.feature.bookmarks.navigation.navigateToBookmarks
-import com.google.samples.apps.nowinandroid.feature.foryou.navigation.FOR_YOU_ROUTE
 import com.google.samples.apps.nowinandroid.feature.foryou.navigation.navigateToForYou
-import com.google.samples.apps.nowinandroid.feature.interests.navigation.INTERESTS_ROUTE
 import com.google.samples.apps.nowinandroid.feature.interests.navigation.navigateToInterests
 import com.google.samples.apps.nowinandroid.feature.search.navigation.navigateToSearch
 import com.google.samples.apps.nowinandroid.navigation.TopLevelDestination
@@ -90,11 +88,10 @@ class NiaAppState(
             .currentBackStackEntryAsState().value?.destination
 
     val currentTopLevelDestination: TopLevelDestination?
-        @Composable get() = when (currentDestination?.route) {
-            FOR_YOU_ROUTE -> FOR_YOU
-            BOOKMARKS_ROUTE -> BOOKMARKS
-            INTERESTS_ROUTE -> INTERESTS
-            else -> null
+        @Composable get() {
+            return TopLevelDestination.entries.firstOrNull { topLevelDestination ->
+                currentDestination?.hasRoute(route = topLevelDestination.route) ?: false
+            }
         }
 
     val isOffline = networkMonitor.isOnline

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

@@ -18,19 +18,26 @@ package com.google.samples.apps.nowinandroid.ui.interests2pane
 
 import androidx.lifecycle.SavedStateHandle
 import androidx.lifecycle.ViewModel
-import com.google.samples.apps.nowinandroid.feature.interests.navigation.TOPIC_ID_ARG
+import androidx.navigation.toRoute
+import com.google.samples.apps.nowinandroid.feature.interests.navigation.InterestsRoute
 import dagger.hilt.android.lifecycle.HiltViewModel
 import kotlinx.coroutines.flow.StateFlow
 import javax.inject.Inject
 
+const val TOPIC_ID_KEY = "selectedTopicId"
+
 @HiltViewModel
 class Interests2PaneViewModel @Inject constructor(
     private val savedStateHandle: SavedStateHandle,
 ) : ViewModel() {
-    val selectedTopicId: StateFlow<String?> =
-        savedStateHandle.getStateFlow(TOPIC_ID_ARG, savedStateHandle[TOPIC_ID_ARG])
+
+    val route = savedStateHandle.toRoute<InterestsRoute>()
+    val selectedTopicId: StateFlow<String?> = savedStateHandle.getStateFlow(
+        key = TOPIC_ID_KEY,
+        initialValue = route.initialTopicId,
+    )
 
     fun onTopicClick(topicId: String?) {
-        savedStateHandle[TOPIC_ID_ARG] = topicId
+        savedStateHandle[TOPIC_ID_KEY] = topicId
     }
 }