Remove SavedStateHandle API

app/src/androidMain/kotlin/io/github/xxfast/decompose/router/app/screens/stack/list/ListViewModel.kt

@@ -0,0 +1,12 @@
+package io.github.xxfast.decompose.router.app.screens.stack.list
+
+import androidx.compose.runtime.Composable
+import androidx.lifecycle.ViewModel
+import io.github.xxfast.decompose.router.rememberOnRoute
+
+class ListViewModel: ViewModel()
+
+@Composable
+fun ListScreen() {
+  val viewModel: ListViewModel = rememberOnRoute(type = ListViewModel::class) { ListViewModel() }
+}

app/src/commonMain/kotlin/io/github/xxfast/decompose/router/screens/stack/list/ListInstance.kt → app/src/commonMain/kotlin/io/github/xxfast/decompose/router/screens/stack/list/ListComponent.kt

@@ -1,32 +1,26 @@
 package io.github.xxfast.decompose.router.screens.stack.list
 
-import com.arkivanov.essenty.instancekeeper.InstanceKeeper.Instance
-import io.github.xxfast.decompose.SavedStateHandle
+import com.arkivanov.decompose.ComponentContext
+import io.github.xxfast.decompose.router.RouterContext
+import io.github.xxfast.decompose.router.state
 import io.github.xxfast.decompose.router.screens.stack.Item
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.cancel
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.launch
 import kotlin.coroutines.CoroutineContext
 
-class ListInstance(private val savedStateHandle: SavedStateHandle) : Instance, CoroutineScope {
-  private val initialState: ListState = savedStateHandle.get() ?: ListState()
-
+class ListComponent(context: RouterContext) : ComponentContext by context, CoroutineScope {
+  private val initialState: ListState = context.state(ListState()) { states.value }
   private val _state: MutableStateFlow<ListState> = MutableStateFlow(initialState)
-  val state: StateFlow<ListState> = _state
+  val states: StateFlow<ListState> = _state
 
   override val coroutineContext: CoroutineContext = Dispatchers.Main
 
   fun add(item: Item = Item(_state.value.screens.size)) = launch {
     val previous: ListState = _state.value
     val updated: ListState = previous.copy(screens = previous.screens.plus(item))
     _state.emit(updated)
-    savedStateHandle.set(updated)
-  }
-
-  override fun onDestroy() {
-    coroutineContext.cancel()
   }
 }

app/src/commonMain/kotlin/io/github/xxfast/decompose/router/screens/stack/list/ListScreen.kt

@@ -40,22 +40,17 @@ import io.github.xxfast.decompose.router.screens.TOOLBAR_TAG
 import io.github.xxfast.decompose.router.screens.stack.Item
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.launch
-import kotlinx.serialization.InternalSerializationApi
-import kotlinx.serialization.serializer
 
-@OptIn(ExperimentalMaterial3Api::class, InternalSerializationApi::class)
+@OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun ListScreen(
   onSelect: (screen: Item) -> Unit,
 ) {
-  val instance: ListInstance = rememberOnRoute(
-    type = ListInstance::class,
-    strategy = ListState::class.serializer()
-  ) { savedState ->
-    ListInstance(savedState)
+  val listComponent: ListComponent = rememberOnRoute(ListComponent::class) { context ->
+    ListComponent(context)
   }
 
-  val state: ListState by instance.state.collectAsState()
+  val state: ListState by listComponent.states.collectAsState()
   val listState: LazyListState = rememberLazyListState()
   val coroutineScope: CoroutineScope = rememberCoroutineScope()
 
@@ -74,7 +69,7 @@ fun ListScreen(
     floatingActionButton = {
       FloatingActionButton(
         onClick = {
-          instance.add()
+          listComponent.add()
           coroutineScope.launch { listState.animateScrollToItem(state.screens.lastIndex) }
         },
         content = { Icon(Icons.Rounded.Add, null) },

decompose-router/api/android/decompose-router.api

@@ -1,23 +1,14 @@
-public final class io/github/xxfast/decompose/KeyKt {
-	public static final fun getKey (Lkotlin/reflect/KClass;)Ljava/lang/String;
-}
-
-public final class io/github/xxfast/decompose/SavedStateHandle : com/arkivanov/essenty/instancekeeper/InstanceKeeper$Instance {
-	public static final field $stable I
-	public fun <init> (Ljava/lang/Object;)V
-	public final fun get ()Ljava/lang/Object;
-	public final fun getValue ()Ljava/lang/Object;
-	public fun onDestroy ()V
-	public final fun set (Ljava/lang/Object;)V
-}
-
 public final class io/github/xxfast/decompose/router/DefaultRouterContextKt {
 	public static final fun defaultRouterContext (Landroidx/activity/ComponentActivity;)Lio/github/xxfast/decompose/router/RouterContext;
 	public static final fun defaultRouterContext (Landroidx/fragment/app/Fragment;Landroidx/activity/OnBackPressedDispatcher;)Lio/github/xxfast/decompose/router/RouterContext;
 }
 
+public final class io/github/xxfast/decompose/router/KeyKt {
+	public static final fun getKey (Lkotlin/reflect/KClass;)Ljava/lang/String;
+}
+
 public final class io/github/xxfast/decompose/router/RememberOnRouteKt {
-	public static final fun rememberOnRoute (Lkotlin/reflect/KClass;Lkotlinx/serialization/KSerializer;Ljava/lang/Object;Lkotlin/jvm/functions/Function1;Landroidx/compose/runtime/Composer;II)Lcom/arkivanov/essenty/instancekeeper/InstanceKeeper$Instance;
+	public static final fun rememberOnRoute (Lkotlin/reflect/KClass;Ljava/lang/Object;Lkotlin/jvm/functions/Function1;Landroidx/compose/runtime/Composer;II)Ljava/lang/Object;
 }
 
 public final class io/github/xxfast/decompose/router/RouterContext : com/arkivanov/decompose/ComponentContext {

decompose-router/api/desktop/decompose-router.api

@@ -1,22 +1,13 @@
-public final class io/github/xxfast/decompose/KeyKt {
-	public static final fun getKey (Lkotlin/reflect/KClass;)Ljava/lang/String;
-}
-
-public final class io/github/xxfast/decompose/SavedStateHandle : com/arkivanov/essenty/instancekeeper/InstanceKeeper$Instance {
-	public static final field $stable I
-	public fun <init> (Ljava/lang/Object;)V
-	public final fun get ()Ljava/lang/Object;
-	public final fun getValue ()Ljava/lang/Object;
-	public fun onDestroy ()V
-	public final fun set (Ljava/lang/Object;)V
-}
-
 public final class io/github/xxfast/decompose/router/DefaultRouterContextKt {
 	public static final fun defaultRouterContext (Lcom/arkivanov/essenty/backhandler/BackDispatcher;Lcom/arkivanov/essenty/lifecycle/LifecycleRegistry;Landroidx/compose/ui/window/WindowState;Landroidx/compose/runtime/Composer;II)Lio/github/xxfast/decompose/router/RouterContext;
 }
 
+public final class io/github/xxfast/decompose/router/KeyKt {
+	public static final fun getKey (Lkotlin/reflect/KClass;)Ljava/lang/String;
+}
+
 public final class io/github/xxfast/decompose/router/RememberOnRouteKt {
-	public static final fun rememberOnRoute (Lkotlin/reflect/KClass;Lkotlinx/serialization/KSerializer;Ljava/lang/Object;Lkotlin/jvm/functions/Function1;Landroidx/compose/runtime/Composer;II)Lcom/arkivanov/essenty/instancekeeper/InstanceKeeper$Instance;
+	public static final fun rememberOnRoute (Lkotlin/reflect/KClass;Ljava/lang/Object;Lkotlin/jvm/functions/Function1;Landroidx/compose/runtime/Composer;II)Ljava/lang/Object;
 }
 
 public final class io/github/xxfast/decompose/router/RouterContext : com/arkivanov/decompose/ComponentContext {

decompose-router/src/desktopMain/kotlin/io/github/xxfast/decompose/Key.kt → decompose-router/src/androidMain/kotlin/io/github/xxfast/decompose/router/Key.kt

@@ -1,4 +1,4 @@
-package io.github.xxfast.decompose
+package io.github.xxfast.decompose.router
 
 import kotlin.reflect.KClass
 

decompose-router/src/commonMain/kotlin/io/github/xxfast/decompose/Key.kt → decompose-router/src/commonMain/kotlin/io/github/xxfast/decompose/router/Key.kt

@@ -1,4 +1,4 @@
-package io.github.xxfast.decompose
+package io.github.xxfast.decompose.router
 
 import kotlin.reflect.KClass
 

decompose-router/src/commonMain/kotlin/io/github/xxfast/decompose/router/RememberOnRoute.kt

@@ -2,51 +2,33 @@ package io.github.xxfast.decompose.router
 
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.DisallowComposableCalls
-import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.remember
 import com.arkivanov.essenty.instancekeeper.InstanceKeeper
-import com.arkivanov.essenty.instancekeeper.getOrCreate
-import com.arkivanov.essenty.statekeeper.StateKeeper
-import io.github.xxfast.decompose.SavedStateHandle
-import io.github.xxfast.decompose.key
-import kotlinx.serialization.KSerializer
-import kotlinx.serialization.Serializable
 import kotlin.reflect.KClass
 
 /***
- * Creates an instance of [T] that is scoped to the current route
+ * Scopes instance of [T] to the current route
  *
  * @param type class of [T] instance
  * @param key key to remember the instance with. Defaults to [type]'s key
- * @param block lambda to create an instance of [T] with a given [SavedStateHandle]
+ * @param block lambda to create an instance of [T] with a given [RouterContext]
  */
 @Composable
-fun <T : InstanceKeeper.Instance, C: @Serializable Any> rememberOnRoute(
+fun <T: Any> rememberOnRoute(
   type: KClass<T>,
-  strategy: KSerializer<C>,
   key: Any = type.key,
-  block: @DisallowComposableCalls (savedState: SavedStateHandle) -> T
+  block: @DisallowComposableCalls (context: RouterContext) -> T
 ): T {
-  val component: RouterContext = LocalRouterContext.current
-  val stateKeeper: StateKeeper = component.stateKeeper
-  val instanceKeeper: InstanceKeeper = component.instanceKeeper
-  val instanceKey = "$key.instance"
-  val stateKey = "$key.state"
-  val (instance, savedState) = remember(key) {
-    val savedState: SavedStateHandle = instanceKeeper
-      .getOrCreate(stateKey) { SavedStateHandle(stateKeeper.consume(stateKey, strategy)) }
-    var instance: T? = instanceKeeper.get(instanceKey) as T?
+  class RouteInstance(val instance: T): InstanceKeeper.Instance
+  val routerContext: RouterContext = LocalRouterContext.current
+  val instanceKeeper: InstanceKeeper = routerContext.instanceKeeper
+  val routeInstance: RouteInstance = remember(key) {
+    var instance: RouteInstance? = instanceKeeper.get(key) as RouteInstance?
     if (instance == null) {
-      instance = block(savedState)
-      instanceKeeper.put(instanceKey, instance)
+      instance = RouteInstance(block(routerContext))
+      instanceKeeper.put(key, instance)
     }
-    instance to savedState
+    instance
   }
-
-  LaunchedEffect(Unit) {
-    if (!stateKeeper.isRegistered(stateKey))
-      stateKeeper.register(stateKey, strategy) { savedState.value as C? }
-  }
-
-  return instance
+  return routeInstance.instance
 }

decompose-router/src/commonMain/kotlin/io/github/xxfast/decompose/router/RouterContext.kt

@@ -8,6 +8,10 @@ import com.arkivanov.essenty.backhandler.BackHandler
 import com.arkivanov.essenty.instancekeeper.InstanceKeeper
 import com.arkivanov.essenty.lifecycle.Lifecycle
 import com.arkivanov.essenty.statekeeper.StateKeeper
+import kotlinx.serialization.InternalSerializationApi
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.Serializable
+import kotlinx.serialization.serializer
 
 class RouterContext(
   private val delegate: ComponentContext,
@@ -23,7 +27,7 @@ class RouterContext(
   val storage: MutableMap<Any, Any> = HashMap()
 }
 
-inline fun <reified T : Any> RouterContext.getOrCreate(key: Any, factory: () -> T) : T {
+inline fun <reified T : Any> RouterContext.getOrCreate(key: Any, factory: () -> T): T {
   var instance: T? = storage[key] as T?
   if (instance == null) {
     instance = factory()
@@ -41,3 +45,15 @@ inline fun <reified T : Any> RouterContext.getOrCreate(key: Any, factory: () ->
  */
 val LocalRouterContext: ProvidableCompositionLocal<RouterContext> =
   staticCompositionLocalOf { error("Root RouterContext was not provided") }
+
+@OptIn(InternalSerializationApi::class)
+inline fun <reified T : @Serializable Any> RouterContext.state(
+  initial: T,
+  key: String = T::class.key,
+  serializer: KSerializer<T> = T::class.serializer(),
+  noinline supplier: () -> T,
+): T {
+  val state: T = stateKeeper.consume(key, serializer) ?: initial
+  if (!stateKeeper.isRegistered(key)) stateKeeper.register(key, serializer, supplier)
+  return state
+}

decompose-router/src/commonMain/kotlin/io/github/xxfast/decompose/State.kt → decompose-router/src/commonMain/kotlin/io/github/xxfast/decompose/router/State.kt

@@ -1,4 +1,4 @@
-package io.github.xxfast.decompose
+package io.github.xxfast.decompose.router
 
 import androidx.compose.runtime.State
 import androidx.compose.runtime.mutableStateOf

decompose-router/src/commonMain/kotlin/io/github/xxfast/decompose/router/pages/Router.kt

@@ -10,9 +10,9 @@ import com.arkivanov.decompose.router.pages.PagesNavigation
 import com.arkivanov.decompose.router.pages.childPages
 import io.github.xxfast.decompose.router.LocalRouterContext
 import io.github.xxfast.decompose.router.RouterContext
-import io.github.xxfast.decompose.asState
+import io.github.xxfast.decompose.router.asState
 import io.github.xxfast.decompose.router.getOrCreate
-import io.github.xxfast.decompose.key
+import io.github.xxfast.decompose.router.key
 import kotlinx.serialization.InternalSerializationApi
 import kotlinx.serialization.KSerializer
 import kotlinx.serialization.Serializable

decompose-router/src/commonMain/kotlin/io/github/xxfast/decompose/router/slot/Router.kt

@@ -6,8 +6,8 @@ import androidx.compose.runtime.remember
 import com.arkivanov.decompose.router.slot.ChildSlot
 import com.arkivanov.decompose.router.slot.SlotNavigation
 import com.arkivanov.decompose.router.slot.childSlot
-import io.github.xxfast.decompose.asState
-import io.github.xxfast.decompose.key
+import io.github.xxfast.decompose.router.asState
+import io.github.xxfast.decompose.router.key
 import io.github.xxfast.decompose.router.LocalRouterContext
 import io.github.xxfast.decompose.router.RouterContext
 import io.github.xxfast.decompose.router.getOrCreate

decompose-router/src/commonMain/kotlin/io/github/xxfast/decompose/router/stack/Router.kt

@@ -8,9 +8,9 @@ import com.arkivanov.decompose.router.stack.StackNavigation
 import com.arkivanov.decompose.router.stack.childStack
 import io.github.xxfast.decompose.router.LocalRouterContext
 import io.github.xxfast.decompose.router.RouterContext
-import io.github.xxfast.decompose.asState
+import io.github.xxfast.decompose.router.asState
 import io.github.xxfast.decompose.router.getOrCreate
-import io.github.xxfast.decompose.key
+import io.github.xxfast.decompose.router.key
 import kotlinx.serialization.*
 import kotlin.reflect.KClass
 

decompose-router/src/iosMain/kotlin/io/github/xxfast/decompose/Key.kt → decompose-router/src/desktopMain/kotlin/io/github/xxfast/decompose/router/Key.kt

@@ -1,4 +1,4 @@
-package io.github.xxfast.decompose
+package io.github.xxfast.decompose.router
 
 import kotlin.reflect.KClass
 

decompose-router/src/androidMain/kotlin/io/github/xxfast/decompose/Key.kt → decompose-router/src/iosMain/kotlin/io/github/xxfast/decompose/router/Key.kt

@@ -1,4 +1,4 @@
-package io.github.xxfast.decompose
+package io.github.xxfast.decompose.router
 
 import kotlin.reflect.KClass
 

decompose-router/src/jsMain/kotlin/io/github/xxfast/decompose/Key.kt → decompose-router/src/jsMain/kotlin/io/github/xxfast/decompose/router/Key.kt

@@ -1,4 +1,4 @@
-package io.github.xxfast.decompose
+package io.github.xxfast.decompose.router
 
 import kotlin.reflect.KClass
 

docs/cfg/buildprofiles.xml

@@ -7,7 +7,7 @@
         <variables>
             <noindex-content>false</noindex-content>
             <color-preset>soft</color-preset>
-            <primary-color>blue</primary-color>
+            <primary-color>red</primary-color>
             <header-logo>decompose_router.svg</header-logo>
             <custom-favicons>fav.svg</custom-favicons>
         </variables>

docs/decompose-router.tree

@@ -12,5 +12,5 @@
         <toc-element topic="using-stack-navigation.md"/>
         <toc-element topic="using-pages-navigation.md"/>
         <toc-element topic="using-slot-navigation.md"/>
-    </toc-element><toc-element topic="Scoping-Instances-to-Screens.md"/>
+    </toc-element><toc-element topic="managing-screen-state.md"/>
     </instance-profile>

docs/topics/installation.md

@@ -26,10 +26,8 @@ decompose-router = { module = "io.github.xxfast:decompose-router", version.ref =
 # For Compose Wear
 decompose-router-wear = { module = "io.github.xxfast:decompose-router-wear", version.ref = "decompose-router" }
 
-# You will need to also bring in decompose and essenty
-decompose = { module = "com.arkivanov.decompose:decompose", version.ref = "decompose" }
+# You will need to also bring in decompose extensions for compose-multiplatform
 decompose-compose-multiplatform = { module = "com.arkivanov.decompose:extensions-compose-jetbrains", version.ref = "decompose" }
-essenty-parcelable = { module = "com.arkivanov.essenty:parcelable", version.ref = "essenty" }
 ```
 
 **build.gradle.kts**