shared: Inject navigation using Koin as well

Largely inspired from https://insert-koin.io/docs/reference/koin-compose/navigation3/
However I adapted certain things as needed.

Signed-off-by: Aayush Gupta <aayushgupta219@gmail.com>

app/src/main/java/org/schabi/newpipe/util/NavigationHelper.java

@@ -26,7 +26,7 @@ import androidx.fragment.app.FragmentTransaction;
 import com.jakewharton.processphoenix.ProcessPhoenix;
 
 import net.newpipe.app.extensions.ContextKt;
-import net.newpipe.app.navigation.Screen;
+import net.newpipe.app.navigation.Destination;
 
 import org.schabi.newpipe.MainActivity;
 import org.schabi.newpipe.NewPipeDatabase;
@@ -684,7 +684,7 @@ public final class NavigationHelper {
     }
 
     public static void openAbout(final Context context) {
-        ContextKt.navigateTo(context, Screen.About.INSTANCE);
+        ContextKt.navigateTo(context, Destination.About.INSTANCE);
     }
 
     public static void openSettings(final Context context) {

gradle/libs.versions.toml

@@ -143,6 +143,7 @@ jetbrains-navigation3-ui = { module = "org.jetbrains.androidx.navigation3:naviga
 jsoup = { module = "org.jsoup:jsoup", version.ref = "jsoup" }
 junit = { module = "junit:junit", version.ref = "junit" }
 koin-annotations = { module = "io.insert-koin:koin-annotations", version.ref = "koin" }
+koin-compose-navigation3 = { module = "io.insert-koin:koin-compose-navigation3", version.ref = "koin" }
 koin-compose-viewmodel = { module = "io.insert-koin:koin-compose-viewmodel", version.ref = "koin" }
 kotlin-test-core = { module = "org.jetbrains.kotlin:kotlin-test", version.ref = "kotlin" }
 kotlinx-coroutines-rx3 = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-rx3", version.ref = "kotlinx-coroutines-rx3" }

shared/build.gradle.kts

@@ -106,6 +106,7 @@ kotlin {
                 implementation(libs.jetbrains.lifecycle.navigation3)
                 implementation(libs.kotlinx.serialization.json)
 
+                implementation(libs.koin.compose.navigation3)
                 implementation(libs.koin.compose.viewmodel)
                 implementation(libs.koin.annotations)
 

shared/src/androidMain/kotlin/net/newpipe/app/ComposeActivity.kt

@@ -14,7 +14,7 @@ import androidx.compose.ui.platform.LocalView
 import androidx.core.view.WindowCompat
 import kotlinx.serialization.json.Json
 import net.newpipe.Constants
-import net.newpipe.app.navigation.Screen
+import net.newpipe.app.navigation.Destination
 import net.newpipe.app.theme.currentService
 
 /**
@@ -28,7 +28,7 @@ class ComposeActivity : ComponentActivity() {
         setContent {
             App(
                 // TODO: Change when everything is in compose and this is the primary activity
-                startDestination = Json.decodeFromString<Screen>(
+                startDestination = Json.decodeFromString<Destination>(
                     intent.getStringExtra(Constants.INTENT_SCREEN_KEY)!!
                 ),
                 onCloseRequest = ::finish

shared/src/androidMain/kotlin/net/newpipe/app/extensions/Context.kt

@@ -10,12 +10,12 @@ import android.content.Intent
 import kotlinx.serialization.json.Json
 import net.newpipe.Constants
 import net.newpipe.app.ComposeActivity
-import net.newpipe.app.navigation.Screen
+import net.newpipe.app.navigation.Destination
 
 /**
  * Navigates to a given compose destination
  */
-fun Context.navigateTo(screen: Screen) = Intent(this, ComposeActivity::class.java).also { intent ->
-    intent.putExtra(Constants.INTENT_SCREEN_KEY, Json.encodeToString(screen))
+fun Context.navigateTo(destination: Destination) = Intent(this, ComposeActivity::class.java).also { intent ->
+    intent.putExtra(Constants.INTENT_SCREEN_KEY, Json.encodeToString(destination))
     startActivity(intent)
 }

shared/src/commonMain/kotlin/net/newpipe/app/App.kt

@@ -7,8 +7,9 @@ package net.newpipe.app
 
 import androidx.compose.runtime.Composable
 import net.newpipe.app.di.KoinApp
+import net.newpipe.app.navigation.Destination
 import net.newpipe.app.navigation.NavDisplay
-import net.newpipe.app.navigation.Screen
+import net.newpipe.app.navigation.navModule
 import net.newpipe.app.theme.AppTheme
 import org.koin.compose.KoinApplication
 import org.koin.plugin.module.dsl.koinConfiguration
@@ -21,11 +22,17 @@ import org.koin.plugin.module.dsl.koinConfiguration
  */
 @Composable
 fun App(
-    startDestination: Screen = Screen.About,
+    startDestination: Destination = Destination.About,
     onCloseRequest: () -> Unit,
     withKoin: @Composable () -> Unit = {}
 ) {
-    KoinApplication(configuration = koinConfiguration<KoinApp>()) {
+    KoinApplication(
+        configuration = koinConfiguration<KoinApp>(
+            appDeclaration = {
+                modules(navModule())
+            }
+        )
+    ) {
         AppTheme {
             NavDisplay(
                 startDestination = startDestination,

shared/src/commonMain/kotlin/net/newpipe/app/navigation/Destination.kt

@@ -0,0 +1,20 @@
+/*
+ * SPDX-FileCopyrightText: 2026 NewPipe e.V. <https://newpipe-ev.de>
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+package net.newpipe.app.navigation
+
+import androidx.navigation3.runtime.NavKey
+import kotlinx.serialization.Serializable
+import net.newpipe.app.model.License
+
+/**
+ * Destinations for navigation in compose
+ */
+@Serializable
+sealed interface Destination : NavKey {
+
+    @Serializable
+    data object About : Destination
+}

shared/src/commonMain/kotlin/net/newpipe/app/navigation/NavDisplay.kt

@@ -6,30 +6,42 @@
 package net.newpipe.app.navigation
 
 import androidx.compose.runtime.Composable
-import androidx.navigation3.runtime.entryProvider
-import androidx.navigation3.runtime.rememberNavBackStack
+import androidx.compose.runtime.saveable.rememberSerializable
+import androidx.lifecycle.viewmodel.navigation3.rememberViewModelStoreNavEntryDecorator
+import androidx.navigation3.runtime.rememberSaveableStateHolderNavEntryDecorator
 import androidx.navigation3.ui.NavDisplay
-import net.newpipe.app.screen.about.AboutScreen
+import androidx.savedstate.compose.serialization.serializers.SnapshotStateListSerializer
+import org.koin.compose.koinInject
+import org.koin.compose.navigation3.koinEntryProvider
+import org.koin.core.annotation.KoinExperimentalAPI
+import org.koin.core.parameter.parametersOf
 
 /**
  * Navigation display for compose screens
  * @param startDestination Starting destination for the app
- * @param onCloseRequest Callback to close app when there are no more screens left in backstack
+ * @param navigator Navigator to help with navigation, injected by Koin
+ * @param onCloseRequest Callback to close the app
  */
+@OptIn(KoinExperimentalAPI::class)
 @Composable
-fun NavDisplay(startDestination: Screen, onCloseRequest: () -> Unit) {
-    val backstack = rememberNavBackStack(screenConfig, startDestination)
-
-    fun onNavigateUp() = if (backstack.size > 1) backstack.removeLastOrNull() else onCloseRequest()
+fun NavDisplay(
+    startDestination: Destination,
+    onCloseRequest: () -> Unit,
+    navigator: Navigator = koinInject {
+        parametersOf(startDestination, onCloseRequest)
+    }
+) {
+    val backstack = rememberSerializable(serializer = SnapshotStateListSerializer<Destination>()) {
+        navigator.backstack
+    }
 
     NavDisplay(
         backStack = backstack,
-        entryProvider = entryProvider {
-            entry<Screen.About> {
-                AboutScreen(
-                    onNavigateUp = ::onNavigateUp
-                )
-            }
-        }
+        onBack = { navigator.navigateUp() },
+        entryDecorators = listOf(
+            rememberSaveableStateHolderNavEntryDecorator(),
+            rememberViewModelStoreNavEntryDecorator()
+        ),
+        entryProvider = koinEntryProvider()
     )
 }

shared/src/commonMain/kotlin/net/newpipe/app/navigation/NavModule.kt

@@ -0,0 +1,65 @@
+/*
+ * SPDX-FileCopyrightText: 2026 NewPipe e.V. <https://newpipe-ev.de>
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+package net.newpipe.app.navigation
+
+import androidx.compose.runtime.mutableStateListOf
+import co.touchlab.kermit.Logger
+import net.newpipe.app.screen.about.AboutScreen
+import org.koin.core.annotation.KoinExperimentalAPI
+import org.koin.core.annotation.Provided
+import org.koin.core.annotation.Singleton
+import org.koin.dsl.module
+import org.koin.dsl.navigation3.navigation
+import org.koin.plugin.module.dsl.single
+
+/**
+ * Navigation module to make navigation easier with nav3
+ *
+ * There is currently no annotation to handle this so we are using DSL API of Koin
+ */
+@OptIn(KoinExperimentalAPI::class)
+fun navModule() = module {
+    single<Navigator>()
+
+    navigation<Destination.About> {
+        AboutScreen()
+    }
+}
+
+/**
+ * Helper to navigate up and to different destinations in compose
+ */
+@Singleton
+class Navigator(
+    @Provided
+    private val startDestination: Destination,
+
+    @Provided
+    private val onCloseRequest: () -> Unit
+) {
+
+    /**
+     * Navigation backstack in compose
+     */
+    val backstack = mutableStateListOf(startDestination)
+
+    /**
+     * Navigates to the given destination
+     */
+    fun navigateTo(destination: Destination) = backstack.add(destination)
+
+    /**
+     * Navigates to the previous entry in the backstack
+     */
+    fun navigateUp() = when {
+        backstack.size > 1 -> backstack.removeLastOrNull()
+
+        else -> {
+            Logger.i(messageString = "Cannot remove the only entry in backstack!")
+            onCloseRequest()
+        }
+    }
+}

shared/src/commonMain/kotlin/net/newpipe/app/navigation/Screen.kt

@@ -1,35 +0,0 @@
-/*
- * SPDX-FileCopyrightText: 2026 NewPipe e.V. <https://newpipe-ev.de>
- * SPDX-License-Identifier: GPL-3.0-or-later
- */
-
-package net.newpipe.app.navigation
-
-import androidx.navigation3.runtime.NavKey
-import androidx.savedstate.serialization.SavedStateConfiguration
-import kotlinx.serialization.ExperimentalSerializationApi
-import kotlinx.serialization.Serializable
-import kotlinx.serialization.modules.SerializersModule
-import kotlinx.serialization.modules.polymorphic
-
-/**
- * Destinations for navigation in compose
- */
-@Serializable
-sealed interface Screen : NavKey {
-
-    @Serializable
-    data object About : Screen
-}
-
-/**
- * Saved state configuration for screens
- */
-@OptIn(ExperimentalSerializationApi::class)
-internal val screenConfig = SavedStateConfiguration {
-    serializersModule = SerializersModule {
-        polymorphic(NavKey::class) {
-            subclassesOfSealed<Screen>()
-        }
-    }
-}

shared/src/commonMain/kotlin/net/newpipe/app/screen/about/AboutScreen.kt

@@ -25,17 +25,19 @@ import androidx.compose.ui.tooling.preview.PreviewWrapper
 import androidx.compose.ui.util.fastForEachIndexed
 import kotlinx.coroutines.launch
 import net.newpipe.app.composable.TopAppBar
+import net.newpipe.app.navigation.Navigator
 import net.newpipe.app.preview.ThemePreviewProvider
 import net.newpipe.app.screen.about.navigation.Page
 import net.newpipe.app.theme.currentServiceScheme
 import newpipe.shared.generated.resources.Res
 import newpipe.shared.generated.resources.title_activity_about
 import org.jetbrains.compose.resources.stringResource
+import org.koin.compose.koinInject
 
 @Composable
-fun AboutScreen(onNavigateUp: () -> Unit) {
+fun AboutScreen(navigator: Navigator = koinInject()) {
     AboutScreenContent(
-        onNavigateUp = onNavigateUp
+        onNavigateUp = { navigator.navigateUp() }
     )
 }