.github/workflows/build-linux.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v1
+        uses: actions/checkout@v3
       - name: Install Java
         uses: actions/setup-java@v1
         with:
@@ -29,10 +29,3 @@ jobs:
             ${{ runner.os }}-gradle-
       - name: Build
         run: ./gradlew build -Dsplit_targets
-      - name: Android instrumentation tests
-        uses: reactivecircus/android-emulator-runner@v2
-        with:
-          api-level: 21
-          arch: x86
-          disable-animations: true
-          script: ./gradlew :extensions-compose-jetpack:connectedDebugAndroidTest --stacktrace

.github/workflows/build-macos.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: macos-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v1
+        uses: actions/checkout@v3
       - name: Install Java
         uses: actions/setup-java@v1
         with:

.github/workflows/publish.yml

@@ -25,7 +25,7 @@ jobs:
     needs: create-staging-repository
     steps:
       - name: Checkout
-        uses: actions/checkout@v1
+        uses: actions/checkout@v3
       - name: Install Java
         uses: actions/setup-java@v1
         with:
@@ -43,7 +43,7 @@ jobs:
     needs: create-staging-repository
     steps:
       - name: Checkout
-        uses: actions/checkout@v1
+        uses: actions/checkout@v3
       - name: Install Java
         uses: actions/setup-java@v1
         with:
@@ -61,7 +61,7 @@ jobs:
     needs: create-staging-repository
     steps:
       - name: Checkout
-        uses: actions/checkout@v1
+        uses: actions/checkout@v3
       - name: Install Java
         uses: actions/setup-java@v1
         with:
@@ -91,7 +91,7 @@ jobs:
     needs: close-staging-repository
     steps:
       - name: Checkout
-        uses: actions/checkout@v1
+        uses: actions/checkout@v3
       - name: Install Java
         uses: actions/setup-java@v1
         with:
@@ -108,7 +108,7 @@ jobs:
     needs: close-staging-repository
     steps:
       - name: Checkout
-        uses: actions/checkout@v1
+        uses: actions/checkout@v3
       - name: Install Java
         uses: actions/setup-java@v1
         with:

README.md

@@ -16,19 +16,18 @@ Please see the [project website](https://arkivanov.github.io/Decompose/) for doc
 
 Decompose is a Kotlin Multiplatform library for breaking down your code into lifecycle-aware business logic components (aka BLoC), with routing functionality and pluggable UI (Jetpack Compose, Android Views, SwiftUI, JS React, etc.).
 
-## ⚡⚡⚡ Why is this repository a fork?
+## ⚡⚡⚡ Where are all the stars, issues, discussions, pull requests, etc?
 
 Having spent 5 years working on a variety of projects for Badoo/Bumble, I’m now off to another adventure. As part of that transition I was asked to transfer this repository to [Badoo GitHub account](https://github.com/badoo).
 
-Now I **continue my work** on this project **as a fork**.
+Now I **continue my work** on this project **as a copy**.
 
 There should be no breaking changes related to this transfer. Most of the external links should not be broken. The repository link is also the same: [arkivanov/Decompose](https://github.com/arkivanov/Decompose). Please file an issue in this repository, if you think something is broken or does not work properly.
 
 Here is what is mostly affected by the transfer:
 
 - All the stars were transferred
-- Search in the code will not work **as long as this repository has less stars than the parent** (your help is needed!)
-- All the Issues and Discussions were transferred as well. I will do all my best to fill the gap here.
+- All the issues and discussions were transferred as well. I will do all my best to fill the gap here.
 - All pull requests with all the comment history are also gone.
 
 I will continue doing all my best for this project and for the community! Business as usual!
@@ -39,6 +38,7 @@ Additional resources:
 
 ## Why Decompose?
 
+* Decompose breaks the code down into small and independent components and organizes them into trees. Each parent component is only aware of its immediate children.
 * Decompose draws clear boundaries between UI and non-UI code, which gives the following benefits:
   * Better separation of concerns
   * Pluggable platform-specific UI (Compose, SwiftUI, React, etc.)

decompose/api/android/decompose.api

@@ -34,11 +34,9 @@ public final class com/arkivanov/decompose/Child$Destroyed : com/arkivanov/decom
 }
 
 public abstract interface class com/arkivanov/decompose/ComponentContext : com/arkivanov/essenty/backpressed/BackPressedHandlerOwner, com/arkivanov/essenty/instancekeeper/InstanceKeeperOwner, com/arkivanov/essenty/lifecycle/LifecycleOwner, com/arkivanov/essenty/statekeeper/StateKeeperOwner {
-	public abstract fun getBackPressedDispatcher ()Lcom/arkivanov/essenty/backpressed/BackPressedDispatcher;
 }
 
 public final class com/arkivanov/decompose/ComponentContextExtKt {
-	public static final fun child (Lcom/arkivanov/decompose/ComponentContext;Ljava/lang/String;)Lcom/arkivanov/decompose/ComponentContext;
 	public static final fun childContext (Lcom/arkivanov/decompose/ComponentContext;Ljava/lang/String;Lcom/arkivanov/essenty/lifecycle/Lifecycle;)Lcom/arkivanov/decompose/ComponentContext;
 	public static synthetic fun childContext$default (Lcom/arkivanov/decompose/ComponentContext;Ljava/lang/String;Lcom/arkivanov/essenty/lifecycle/Lifecycle;ILjava/lang/Object;)Lcom/arkivanov/decompose/ComponentContext;
 }
@@ -47,7 +45,6 @@ public final class com/arkivanov/decompose/DefaultComponentContext : com/arkivan
 	public fun <init> (Lcom/arkivanov/essenty/lifecycle/Lifecycle;)V
 	public fun <init> (Lcom/arkivanov/essenty/lifecycle/Lifecycle;Lcom/arkivanov/essenty/statekeeper/StateKeeper;Lcom/arkivanov/essenty/instancekeeper/InstanceKeeper;Lcom/arkivanov/essenty/backpressed/BackPressedHandler;)V
 	public synthetic fun <init> (Lcom/arkivanov/essenty/lifecycle/Lifecycle;Lcom/arkivanov/essenty/statekeeper/StateKeeper;Lcom/arkivanov/essenty/instancekeeper/InstanceKeeper;Lcom/arkivanov/essenty/backpressed/BackPressedHandler;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
-	public fun getBackPressedDispatcher ()Lcom/arkivanov/essenty/backpressed/BackPressedDispatcher;
 	public fun getBackPressedHandler ()Lcom/arkivanov/essenty/backpressed/BackPressedHandler;
 	public fun getInstanceKeeper ()Lcom/arkivanov/essenty/instancekeeper/InstanceKeeper;
 	public fun getLifecycle ()Lcom/arkivanov/essenty/lifecycle/Lifecycle;
@@ -75,13 +72,15 @@ public final class com/arkivanov/decompose/lifecycle/MergedLifecycle : com/arkiv
 
 public abstract interface class com/arkivanov/decompose/router/Router {
 	public abstract fun getState ()Lcom/arkivanov/decompose/value/Value;
-	public abstract fun navigate (Lkotlin/jvm/functions/Function1;)V
+	public abstract fun navigate (Lkotlin/jvm/functions/Function1;Lkotlin/jvm/functions/Function2;)V
 }
 
 public final class com/arkivanov/decompose/router/RouterExtKt {
 	public static final fun bringToFront (Lcom/arkivanov/decompose/router/Router;Ljava/lang/Object;)V
 	public static final fun getActiveChild (Lcom/arkivanov/decompose/router/Router;)Lcom/arkivanov/decompose/Child$Created;
-	public static final fun pop (Lcom/arkivanov/decompose/router/Router;)V
+	public static final fun navigate (Lcom/arkivanov/decompose/router/Router;Lkotlin/jvm/functions/Function1;)V
+	public static final fun pop (Lcom/arkivanov/decompose/router/Router;Lkotlin/jvm/functions/Function1;)V
+	public static synthetic fun pop$default (Lcom/arkivanov/decompose/router/Router;Lkotlin/jvm/functions/Function1;ILjava/lang/Object;)V
 	public static final fun popWhile (Lcom/arkivanov/decompose/router/Router;Lkotlin/jvm/functions/Function1;)V
 	public static final fun push (Lcom/arkivanov/decompose/router/Router;Ljava/lang/Object;)V
 	public static final fun replaceCurrent (Lcom/arkivanov/decompose/router/Router;Ljava/lang/Object;)V
@@ -109,6 +108,22 @@ public final class com/arkivanov/decompose/router/RouterState {
 	public fun toString ()Ljava/lang/String;
 }
 
+public final class com/arkivanov/decompose/router/StackSaverImpl$SavedEntry$Creator : android/os/Parcelable$Creator {
+	public fun <init> ()V
+	public final fun createFromParcel (Landroid/os/Parcel;)Lcom/arkivanov/decompose/router/StackSaverImpl$SavedEntry;
+	public synthetic fun createFromParcel (Landroid/os/Parcel;)Ljava/lang/Object;
+	public final fun newArray (I)[Lcom/arkivanov/decompose/router/StackSaverImpl$SavedEntry;
+	public synthetic fun newArray (I)[Ljava/lang/Object;
+}
+
+public final class com/arkivanov/decompose/router/StackSaverImpl$SavedState$Creator : android/os/Parcelable$Creator {
+	public fun <init> ()V
+	public final fun createFromParcel (Landroid/os/Parcel;)Lcom/arkivanov/decompose/router/StackSaverImpl$SavedState;
+	public synthetic fun createFromParcel (Landroid/os/Parcel;)Ljava/lang/Object;
+	public final fun newArray (I)[Lcom/arkivanov/decompose/router/StackSaverImpl$SavedState;
+	public synthetic fun newArray (I)[Ljava/lang/Object;
+}
+
 public abstract interface class com/arkivanov/decompose/router/webhistory/WebHistoryController {
 	public abstract fun attach (Lcom/arkivanov/decompose/router/Router;Lkotlin/jvm/functions/Function1;Lkotlin/jvm/functions/Function1;)V
 }

decompose/api/jvm/decompose.api

@@ -27,11 +27,9 @@ public final class com/arkivanov/decompose/Child$Destroyed : com/arkivanov/decom
 }
 
 public abstract interface class com/arkivanov/decompose/ComponentContext : com/arkivanov/essenty/backpressed/BackPressedHandlerOwner, com/arkivanov/essenty/instancekeeper/InstanceKeeperOwner, com/arkivanov/essenty/lifecycle/LifecycleOwner, com/arkivanov/essenty/statekeeper/StateKeeperOwner {
-	public abstract fun getBackPressedDispatcher ()Lcom/arkivanov/essenty/backpressed/BackPressedDispatcher;
 }
 
 public final class com/arkivanov/decompose/ComponentContextExtKt {
-	public static final fun child (Lcom/arkivanov/decompose/ComponentContext;Ljava/lang/String;)Lcom/arkivanov/decompose/ComponentContext;
 	public static final fun childContext (Lcom/arkivanov/decompose/ComponentContext;Ljava/lang/String;Lcom/arkivanov/essenty/lifecycle/Lifecycle;)Lcom/arkivanov/decompose/ComponentContext;
 	public static synthetic fun childContext$default (Lcom/arkivanov/decompose/ComponentContext;Ljava/lang/String;Lcom/arkivanov/essenty/lifecycle/Lifecycle;ILjava/lang/Object;)Lcom/arkivanov/decompose/ComponentContext;
 }
@@ -40,7 +38,6 @@ public final class com/arkivanov/decompose/DefaultComponentContext : com/arkivan
 	public fun <init> (Lcom/arkivanov/essenty/lifecycle/Lifecycle;)V
 	public fun <init> (Lcom/arkivanov/essenty/lifecycle/Lifecycle;Lcom/arkivanov/essenty/statekeeper/StateKeeper;Lcom/arkivanov/essenty/instancekeeper/InstanceKeeper;Lcom/arkivanov/essenty/backpressed/BackPressedHandler;)V
 	public synthetic fun <init> (Lcom/arkivanov/essenty/lifecycle/Lifecycle;Lcom/arkivanov/essenty/statekeeper/StateKeeper;Lcom/arkivanov/essenty/instancekeeper/InstanceKeeper;Lcom/arkivanov/essenty/backpressed/BackPressedHandler;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
-	public fun getBackPressedDispatcher ()Lcom/arkivanov/essenty/backpressed/BackPressedDispatcher;
 	public fun getBackPressedHandler ()Lcom/arkivanov/essenty/backpressed/BackPressedHandler;
 	public fun getInstanceKeeper ()Lcom/arkivanov/essenty/instancekeeper/InstanceKeeper;
 	public fun getLifecycle ()Lcom/arkivanov/essenty/lifecycle/Lifecycle;
@@ -62,13 +59,15 @@ public final class com/arkivanov/decompose/lifecycle/MergedLifecycle : com/arkiv
 
 public abstract interface class com/arkivanov/decompose/router/Router {
 	public abstract fun getState ()Lcom/arkivanov/decompose/value/Value;
-	public abstract fun navigate (Lkotlin/jvm/functions/Function1;)V
+	public abstract fun navigate (Lkotlin/jvm/functions/Function1;Lkotlin/jvm/functions/Function2;)V
 }
 
 public final class com/arkivanov/decompose/router/RouterExtKt {
 	public static final fun bringToFront (Lcom/arkivanov/decompose/router/Router;Ljava/lang/Object;)V
 	public static final fun getActiveChild (Lcom/arkivanov/decompose/router/Router;)Lcom/arkivanov/decompose/Child$Created;
-	public static final fun pop (Lcom/arkivanov/decompose/router/Router;)V
+	public static final fun navigate (Lcom/arkivanov/decompose/router/Router;Lkotlin/jvm/functions/Function1;)V
+	public static final fun pop (Lcom/arkivanov/decompose/router/Router;Lkotlin/jvm/functions/Function1;)V
+	public static synthetic fun pop$default (Lcom/arkivanov/decompose/router/Router;Lkotlin/jvm/functions/Function1;ILjava/lang/Object;)V
 	public static final fun popWhile (Lcom/arkivanov/decompose/router/Router;Lkotlin/jvm/functions/Function1;)V
 	public static final fun push (Lcom/arkivanov/decompose/router/Router;Ljava/lang/Object;)V
 	public static final fun replaceCurrent (Lcom/arkivanov/decompose/router/Router;Ljava/lang/Object;)V

decompose/src/commonMain/kotlin/com/arkivanov/decompose/ComponentContext.kt

@@ -1,6 +1,5 @@
 package com.arkivanov.decompose
 
-import com.arkivanov.essenty.backpressed.BackPressedDispatcher
 import com.arkivanov.essenty.backpressed.BackPressedHandlerOwner
 import com.arkivanov.essenty.instancekeeper.InstanceKeeperOwner
 import com.arkivanov.essenty.lifecycle.LifecycleOwner
@@ -10,13 +9,4 @@ interface ComponentContext :
     LifecycleOwner,
     StateKeeperOwner,
     InstanceKeeperOwner,
-    BackPressedHandlerOwner {
-
-    @Deprecated(
-        message = "ComponentContext now extends BackPressedHandlerOwner instead of BackPressedDispatcherOwner. " +
-            "Please use backPressedHandler property.",
-        replaceWith = ReplaceWith("backPressedHandler"),
-        level = DeprecationLevel.ERROR,
-    )
-    val backPressedDispatcher: BackPressedDispatcher
-}
+    BackPressedHandlerOwner

decompose/src/commonMain/kotlin/com/arkivanov/decompose/ComponentContextExt.kt

@@ -22,10 +22,3 @@ fun ComponentContext.childContext(key: String, lifecycle: Lifecycle? = null): Co
         instanceKeeper = instanceKeeper.child(key, lifecycle),
         backPressedHandler = backPressedHandler.child(lifecycle),
     )
-
-@Deprecated(
-    message = "Use childContext(key)",
-    replaceWith = ReplaceWith("childContext(key)"),
-    level = DeprecationLevel.ERROR,
-)
-fun ComponentContext.child(key: String): ComponentContext = childContext(key = key)

decompose/src/commonMain/kotlin/com/arkivanov/decompose/DefaultComponentContext.kt

@@ -20,12 +20,6 @@ class DefaultComponentContext(
     override val instanceKeeper: InstanceKeeper = instanceKeeper ?: InstanceKeeperDispatcher().attachTo(lifecycle)
     override val backPressedHandler: BackPressedHandler = backPressedHandler ?: BackPressedDispatcher()
 
-    override val backPressedDispatcher: BackPressedDispatcher by lazy {
-        BackPressedDispatcher().also { dispatcher ->
-            this.backPressedHandler.register(dispatcher::onBackPressed)
-        }
-    }
-
     constructor(lifecycle: Lifecycle) : this(
         lifecycle = lifecycle,
         stateKeeper = null,

decompose/src/commonMain/kotlin/com/arkivanov/decompose/router/Router.kt

@@ -14,10 +14,20 @@ interface Router<C : Any, out T : Any> {
      * The stack is represented as [List], where the last element is the top of the stack,
      * and the first element is the bottom of the stack. The returned stack must not be empty.
      *
-     * The [Router] compares the current stack with new one returned by the [transformer] function.
-     * New components are created for all new configurations in the stack, and all components
-     * that are no longer in the stack are destroyed. The amount and  order of components in the
-     * resulting stack matches the amount and order of configurations returned by the [transformer].
+     * During the navigation process, the `Router` compares the new stack of configurations with
+     * the previous one. The `Router` ensures that all removed components are destroyed, and that
+     * there is only one component resumed at a time - the top one. All components in the back stack
+     * are always either stopped or destroyed.
+     *
+     * The `Router` usually performs the navigation synchronously, which means that by the time
+     * the `navigate` method returns, the navigation is finished and all component lifecycles are
+     * moved into required states. However the navigation is performed asynchronously in case of
+     * recursive invocations - e.g. `pop` is called from `onResume` lifecycle callback of a
+     * component being pushed. All recursive invocations are queued and performed one by one once
+     * the current navigation is finished.
+     *
+     * @param transformer transforms the current configuration stack to a new one.
+     * @param onComplete called when the navigation is finished (either synchronously or asynchronously).
      */
-    fun navigate(transformer: (stack: List<C>) -> List<C>)
+    fun navigate(transformer: (stack: List<C>) -> List<C>, onComplete: (newStack: List<C>, oldStack: List<C>) -> Unit)
 }

decompose/src/commonMain/kotlin/com/arkivanov/decompose/router/RouterExt.kt

@@ -3,17 +3,31 @@ package com.arkivanov.decompose.router
 import com.arkivanov.decompose.Child
 
 /**
- * Pushes the provided [configuration] at the top of the stack
+ * A convenience method for [Router.navigate].
+ */
+fun <C : Any> Router<C, *>.navigate(transformer: (stack: List<C>) -> List<C>) {
+    navigate(transformer = transformer, onComplete = { _, _ -> })
+}
+
+/**
+ * Pushes the provided [configuration] at the top of the stack..
  */
 fun <C : Any> Router<C, *>.push(configuration: C) {
     navigate { it + configuration }
 }
 
 /**
- * Pops the latest configuration at the top of the stack
+ * Pops the latest configuration at the top of the stack.
+ *
+ * @param onComplete called when the navigation is finished (either synchronously or asynchronously).
+ * The `isSuccess` argument is `true` if the stack size was greater than 1 and a component was popped,
+ * `false` otherwise.
  */
-fun <C : Any> Router<C, *>.pop() {
-    navigate { it.dropLast(1) }
+fun <C : Any> Router<C, *>.pop(onComplete: (isSuccess: Boolean) -> Unit = {}) {
+    navigate(
+        transformer = { stack -> stack.takeIf { it.size > 1 }?.dropLast(1) ?: stack },
+        onComplete = { newStack, oldStack -> onComplete(newStack.size < oldStack.size) }
+    )
 }
 
 /**
@@ -24,7 +38,7 @@ inline fun <C : Any> Router<C, *>.popWhile(crossinline predicate: (C) -> Boolean
 }
 
 /**
- * Replaces the current configuration at the top of the stack with the provided [configuration]
+ * Replaces the current configuration at the top of the stack with the provided [configuration].
  */
 fun <C : Any> Router<C, *>.replaceCurrent(configuration: C) {
     navigate { it.dropLast(1) + configuration }

decompose/src/commonMain/kotlin/com/arkivanov/decompose/router/RouterFactoryExt.kt

@@ -83,7 +83,10 @@ inline fun <reified C : Parcelable, T : Any> ComponentContext.router(
  * A convenience extension function for [ComponentContext.router].
  */
 @Suppress("DeprecatedCallableAddReplaceWith")
-@Deprecated(message = "Please use ComponentContext.router extension function with initialStack argument")
+@Deprecated(
+    message = "Please use ComponentContext.router extension function with initialStack argument",
+    level = DeprecationLevel.ERROR,
+)
 fun <C : Parcelable, T : Any> ComponentContext.router(
     initialConfiguration: () -> C,
     initialBackStack: () -> List<C> = ::emptyList,
@@ -103,8 +106,11 @@ fun <C : Parcelable, T : Any> ComponentContext.router(
 /**
  * A convenience extension function for [ComponentContext.router].
  */
-@Suppress("DeprecatedCallableAddReplaceWith")
-@Deprecated(message = "Please use ComponentContext.router extension function with initialStack argument")
+@Suppress("DeprecatedCallableAddReplaceWith", "DEPRECATION_ERROR")
+@Deprecated(
+    message = "Please use ComponentContext.router extension function with initialStack argument",
+    level = DeprecationLevel.ERROR,
+)
 inline fun <reified C : Parcelable, T : Any> ComponentContext.router(
     initialConfiguration: C,
     initialBackStack: List<C> = emptyList(),
@@ -124,8 +130,11 @@ inline fun <reified C : Parcelable, T : Any> ComponentContext.router(
 /**
  * A convenience extension function for [ComponentContext.router].
  */
-@Suppress("DeprecatedCallableAddReplaceWith")
-@Deprecated(message = "Please use ComponentContext.router extension function with initialStack argument")
+@Suppress("DeprecatedCallableAddReplaceWith", "DEPRECATION_ERROR")
+@Deprecated(
+    message = "Please use ComponentContext.router extension function with initialStack argument",
+    level = DeprecationLevel.ERROR,
+)
 inline fun <reified C : Parcelable, T : Any> ComponentContext.router(
     noinline initialConfiguration: () -> C,
     noinline initialBackStack: () -> List<C> = ::emptyList,

decompose/src/commonMain/kotlin/com/arkivanov/decompose/router/RouterImpl.kt

@@ -33,14 +33,16 @@ internal class RouterImpl<C : Any, T : Any>(
         backPressedHandler.unregister(onBackPressedHandler)
     }
 
-    override fun navigate(transformer: (stack: List<C>) -> List<C>) {
-        queue.offer(transformer)
+    override fun navigate(transformer: (stack: List<C>) -> List<C>, onComplete: (newStack: List<C>, oldStack: List<C>) -> Unit) {
+        queue.offer(NavigationItem(transformer = transformer, onComplete = onComplete))
     }
 
-    private fun navigateActual(transformer: (stack: List<C>) -> List<C>) {
-        val newStack = navigator.navigate(oldStack = stackHolder.stack, transformer = transformer)
+    private fun navigateActual(item: NavigationItem<C>) {
+        val oldStack = stackHolder.stack
+        val newStack = navigator.navigate(oldStack = oldStack, transformer = item.transformer)
         stackHolder.stack = newStack
         state.value = newStack.toState()
+        item.onComplete(newStack.configurationStack, oldStack.configurationStack)
     }
 
     private fun onBackPressed(): Boolean =
@@ -66,4 +68,9 @@ internal class RouterImpl<C : Any, T : Any>(
             is RouterEntry.Created -> Child.Created(configuration = configuration, instance = instance)
             is RouterEntry.Destroyed -> Child.Destroyed(configuration = configuration)
         }
+
+    private class NavigationItem<C : Any>(
+        val transformer: (stack: List<C>) -> List<C>,
+        val onComplete: (newStack: List<C>, oldStack: List<C>) -> Unit,
+    )
 }

decompose/src/commonMain/kotlin/com/arkivanov/decompose/router/RouterStackExt.kt

@@ -0,0 +1,17 @@
+package com.arkivanov.decompose.router
+
+internal val <C : Any> RouterStack<C, *>.configurationBackStack: List<C>
+    get() =
+        object : AbstractList<C>() {
+            override val size: Int get() = backStack.size
+
+            override fun get(index: Int): C = backStack[index].configuration
+        }
+
+internal val <C : Any> RouterStack<C, *>.configurationStack: List<C>
+    get() =
+        object : AbstractList<C>() {
+            override val size: Int get() = backStack.size + 1
+
+            override fun get(index: Int): C = (backStack.getOrNull(index) ?: active).configuration
+        }

decompose/src/commonMain/kotlin/com/arkivanov/decompose/router/StackNavigatorImpl.kt

@@ -11,7 +11,12 @@ internal class StackNavigatorImpl<C : Any, T : Any>(
 ) : StackNavigator<C, T> {
 
     override fun navigate(oldStack: RouterStack<C, T>, transformer: (stack: List<C>) -> List<C>): RouterStack<C, T> {
-        val newConfigurationStack = transformer((oldStack.backStack + oldStack.active).map(RouterEntry<C, *>::configuration))
+        val oldConfigurationStack = oldStack.configurationStack
+        val newConfigurationStack = transformer(oldConfigurationStack)
+
+        if (newConfigurationStack === oldConfigurationStack) {
+            return oldStack
+        }
 
         check(newConfigurationStack.isNotEmpty()) { "Configuration stack can not be empty" }
         check(newConfigurationStack.isUnique()) { "Configurations in the stack must be unique" }

decompose/src/commonTest/kotlin/com/arkivanov/decompose/ChildContextTest.kt

@@ -251,7 +251,5 @@ class ChildContextTest {
         override val lifecycle: LifecycleRegistry = LifecycleRegistry()
         override val stateKeeper: TestStateKeeperDispatcher = TestStateKeeperDispatcher(savedState)
         override val backPressedHandler: BackPressedDispatcher = BackPressedDispatcher()
-
-        override val backPressedDispatcher: BackPressedDispatcher get() = TODO("Not yet implemented")
     }
 }

decompose/src/commonTest/kotlin/com/arkivanov/decompose/router/RouterPopTest.kt

@@ -0,0 +1,54 @@
+package com.arkivanov.decompose.router
+
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+@Suppress("TestFunctionName")
+class RouterPopTest {
+
+    @Test
+    fun GIVEN_stack_size_2_WHEN_pop_THEN_popped() {
+        val router = TestRouter(listOf(Config.A, Config.B))
+
+        router.pop()
+
+        assertEquals(listOf(Config.A), router.stack)
+    }
+
+    @Test
+    fun GIVEN_stack_size_2_WHEN_pop_THEN_onComplete_success() {
+        val router = TestRouter(listOf(Config.A, Config.B))
+        var isSuccess = false
+
+        router.pop { isSuccess = it }
+
+        assertTrue(isSuccess)
+    }
+
+    @Test
+    fun GIVEN_stack_size_1_WHEN_pop_THEN_not_popped() {
+        val router = TestRouter(listOf(Config.A))
+
+        router.pop()
+
+        assertEquals(listOf(Config.A), router.stack)
+    }
+
+
+    @Test
+    fun GIVEN_stack_size_1_WHEN_pop_THEN_onComplete_not_success() {
+        val router = TestRouter(listOf(Config.A))
+        var isSuccess = true
+
+        router.pop { isSuccess = it }
+
+        assertFalse(isSuccess)
+    }
+
+    private sealed class Config {
+        object A : Config()
+        object B : Config()
+    }
+}

decompose/src/commonTest/kotlin/com/arkivanov/decompose/router/RouterTest.kt

@@ -8,86 +8,147 @@ import com.arkivanov.essenty.parcelable.Parcelable
 import com.arkivanov.essenty.parcelable.Parcelize
 import kotlin.test.Test
 import kotlin.test.assertEquals
+import kotlin.test.assertFalse
 
 @Suppress("TestFunctionName")
 class RouterTest {
 
-    private val navigator = TestStackNavigator()
-
     @Test
     fun WHEN_navigate_THEN_new_stack_applied() {
         val config1 = Config()
         val config2 = Config()
         val config3 = Config()
         val config4 = Config()
-
         val router = router(initialStack = listOf(config1, config2, config3))
 
-        navigator.add(
-            configs = listOf(config1, config3, config4),
-            stack = { routerStack(listOf(config1, config3, config4)) }
-        )
-
         router.navigate { listOf(config1, config3, config4) }
 
         assertEquals(listOf(config1, config3, config4), router.configurations)
     }
 
+    @Test
+    fun WHEN_navigate_THEN_onComplete_called_synchronously() {
+        val config1 = Config()
+        val config2 = Config()
+        val config3 = Config()
+        val config4 = Config()
+        val router = router(initialStack = listOf(config1, config2, config3))
+
+        var resultNewStack: List<Config>? = null
+        var resultOldStack: List<Config>? = null
+        router.navigate(transformer = { listOf(config1, config3, config4) }) { newStack, oldStack ->
+            resultNewStack = newStack
+            resultOldStack = oldStack
+        }
+
+        assertEquals(listOf(config1, config3, config4), resultNewStack)
+        assertEquals(listOf(config1, config2, config3), resultOldStack)
+    }
+
     @Test
     fun WHEN_navigate_recursively_THEN_last_stack_applied() {
         val config1 = Config()
         val config2 = Config()
         val config3 = Config()
+        val navigator = TestStackNavigator()
+        val router = router(initialStack = listOf(config1), navigator = navigator)
+
+        navigator.onNavigate =
+            { newConfigs ->
+                if (newConfigs == listOf(config2)) {
+                    router.navigate { listOf(config3) }
+                }
+            }
 
-        val router = router(initialStack = listOf(config1))
+        router.navigate { listOf(config2) }
 
-        navigator.add(
-            configs = listOf(config2),
-            stack = {
-                router.navigate { listOf(config3) }
-                routerStack(listOf(config2))
+        assertEquals(listOf(config3), router.configurations)
+    }
+
+
+    @Test
+    fun WHEN_navigate_recursively_THEN_onComplete_not_called_synchronously() {
+        val config1 = Config()
+        val config2 = Config()
+        val config3 = Config()
+        val navigator = TestStackNavigator()
+        val router = router(initialStack = listOf(config1), navigator = navigator)
+
+        var isCalledSynchronously = false
+        navigator.onNavigate =
+            { newConfigs ->
+                if (newConfigs == listOf(config2)) {
+                    var isCalled = false
+                    router.navigate(transformer = { listOf(config3) }) { _, _ ->
+                        isCalled = true
+                    }
+                    isCalledSynchronously = isCalled
+                }
             }
-        )
 
-        navigator.add(
-            configs = listOf(config3),
-            stack = { routerStack(listOf(config3)) }
-        )
+        router.navigate { listOf(config2) }
+
+        assertFalse(isCalledSynchronously)
+    }
+
+
+    @Test
+    fun WHEN_navigate_recursively_THEN_onComplete_called() {
+        val config1 = Config()
+        val config2 = Config()
+        val config3 = Config()
+        val navigator = TestStackNavigator()
+        val router = router(initialStack = listOf(config1), navigator = navigator)
+
+        var resultNewStack: List<Config>? = null
+        var resultOldStack: List<Config>? = null
+        navigator.onNavigate =
+            { newConfigs ->
+                if (newConfigs == listOf(config2)) {
+                    router.navigate(transformer = { listOf(config3) }) { newStack, oldStack ->
+                        resultNewStack = newStack
+                        resultOldStack = oldStack
+                    }
+                }
+            }
 
         router.navigate { listOf(config2) }
 
-        assertEquals(listOf(config3), router.configurations)
+        assertEquals(listOf(config3), resultNewStack)
+        assertEquals(listOf(config2), resultOldStack)
     }
 
-    private fun router(initialStack: List<Config>): Router<Config, Config> =
+    private fun router(initialStack: List<Config>, navigator: TestStackNavigator = TestStackNavigator()): Router<Config, Config> =
         RouterImpl(
             lifecycle = LifecycleRegistry(),
             backPressedHandler = BackPressedDispatcher(),
             popOnBackPressed = false,
             stackHolder = TestStackHolder(routerStack(initialStack)),
-            navigator = navigator
+            navigator = navigator,
         )
 
-    private fun routerStack(stack: List<Config>): RouterStack<Config, Config> =
-        RouterStack(
-            active = RouterEntry.Created(
-                configuration = stack.last(),
-                instance = stack.last(),
-                lifecycleRegistry = LifecycleRegistry(),
-                stateKeeperDispatcher = TestStateKeeperDispatcher(),
-                instanceKeeperDispatcher = InstanceKeeperDispatcher(),
-                backPressedDispatcher = BackPressedDispatcher()
-            ),
-            backStack = stack.dropLast(1).map {
-                RouterEntry.Destroyed(configuration = it)
-            }
-        )
-
-    private val Router<Config, *>.configurations: List<Config>
-        get() = state.value.configurations
-
-    private val RouterState<Config, *>.configurations: List<Config>
-        get() = backStack.map { it.configuration } + activeChild.configuration
+    private companion object {
+        private fun routerStack(stack: List<Config>): RouterStack<Config, Config> =
+            RouterStack(
+                active = RouterEntry.Created(
+                    configuration = stack.last(),
+                    instance = stack.last(),
+                    lifecycleRegistry = LifecycleRegistry(),
+                    stateKeeperDispatcher = TestStateKeeperDispatcher(),
+                    instanceKeeperDispatcher = InstanceKeeperDispatcher(),
+                    backPressedDispatcher = BackPressedDispatcher()
+                ),
+                backStack = stack.dropLast(1).map {
+                    RouterEntry.Destroyed(configuration = it)
+                }
+            )
+
+        private val Router<Config, *>.configurations: List<Config>
+            get() = state.value.configurations
+
+        private val RouterState<Config, *>.configurations: List<Config>
+            get() = backStack.map { it.configuration } + activeChild.configuration
+    }
 
     @Parcelize
     private class Config : Parcelable
@@ -97,20 +158,17 @@ class RouterTest {
     ) : StackHolder<Config, Config>
 
     private class TestStackNavigator : StackNavigator<Config, Config> {
-        private val map = HashMap<List<Config>, () -> RouterStack<Config, Config>>()
+        var onNavigate: (newConfigs: List<Config>) -> Unit = {}
 
         override fun navigate(
             oldStack: RouterStack<Config, Config>,
             transformer: (stack: List<Config>) -> List<Config>
         ): RouterStack<Config, Config> {
-            val oldConfigs = (oldStack.backStack + oldStack.active).map { it.configuration }
+            val oldConfigs = oldStack.configurationStack
             val newConfigs = transformer(oldConfigs)
+            onNavigate(newConfigs)
 
-            return map.getValue(newConfigs).invoke()
-        }
-
-        fun add(configs: List<Config>, stack: () -> RouterStack<Config, Config>) {
-            map[configs] = stack
+            return routerStack(newConfigs)
         }
     }
 }

decompose/src/commonTest/kotlin/com/arkivanov/decompose/router/StackNavigatorTest.kt

@@ -51,7 +51,7 @@ class StackNavigatorTest {
                 transformer = { it + Config() }
             )
 
-        assertEquals(listOf(oldConfig), newStack.getConfigurationBackStack())
+        assertEquals(listOf(oldConfig), newStack.configurationBackStack)
     }
 
     @Test
@@ -69,37 +69,35 @@ class StackNavigatorTest {
                 transformer = { it + Config() }
             )
 
-        assertEquals(listOf(oldConfig1, oldConfig2, oldConfig3), newStack.getConfigurationBackStack())
+        assertEquals(listOf(oldConfig1, oldConfig2, oldConfig3), newStack.configurationBackStack)
     }
 
     @Test
     fun GIVEN_empty_back_stack_WHEN_push_THEN_old_component_not_recreated() {
-        val newStack =
-            navigator.navigate(
-                oldStack = RouterStack(
-                    active = activeEntry(configuration = Config()),
-                    backStack = emptyList()
-                ),
-                transformer = { it + Config() }
+        val oldStack =
+            RouterStack(
+                active = activeEntry(configuration = Config()),
+                backStack = emptyList()
             )
 
-        assertEquals(1, (newStack.backStack[0] as RouterEntry.Created).instance.instanceNumber)
+        val newStack = navigator.navigate(oldStack = oldStack, transformer = { it + Config() })
+
+        assertSame(newStack.backStack[0].asCreated().instance, oldStack.active.instance)
     }
 
     @Test
     fun GIVEN_not_empty_back_stack_WHEN_push_THEN_old_components_not_recreated() {
-        val newStack =
-            navigator.navigate(
-                oldStack = RouterStack(
-                    active = activeEntry(configuration = Config()),
-                    backStack = listOf(createdEntry(configuration = Config()), createdEntry(configuration = Config()))
-                ),
-                transformer = { it + Config() }
+        val oldStack =
+            RouterStack(
+                active = activeEntry(configuration = Config()),
+                backStack = listOf(createdEntry(configuration = Config()), createdEntry(configuration = Config()))
             )
 
-        assertEquals(1, (newStack.backStack[0] as RouterEntry.Created).instance.instanceNumber)
-        assertEquals(1, (newStack.backStack[1] as RouterEntry.Created).instance.instanceNumber)
-        assertEquals(1, (newStack.backStack[2] as RouterEntry.Created).instance.instanceNumber)
+        val newStack = navigator.navigate(oldStack = oldStack, transformer = { it + Config() })
+
+        assertSame(oldStack.backStack[0].asCreated().instance, newStack.backStack[0].asCreated().instance)
+        assertSame(oldStack.backStack[1].asCreated().instance, newStack.backStack[1].asCreated().instance)
+        assertSame(oldStack.active.instance, newStack.backStack[2].asCreated().instance)
     }
 
     @Test
@@ -240,17 +238,16 @@ class StackNavigatorTest {
 
     @Test
     fun GIVEN_back_stack_WHEN_pop_THEN_old_components_not_recreated() {
-        val newStack =
-            navigator.navigate(
-                oldStack = RouterStack(
-                    active = activeEntry(configuration = Config()),
-                    backStack = listOf(createdEntry(configuration = Config()), createdEntry(configuration = Config()))
-                ),
-                transformer = { it.dropLast(1) }
+        val oldStack =
+            RouterStack(
+                active = activeEntry(configuration = Config()),
+                backStack = listOf(createdEntry(configuration = Config()), createdEntry(configuration = Config()))
             )
 
-        assertEquals(1, (newStack.backStack[0] as RouterEntry.Created).instance.instanceNumber)
-        assertEquals(1, newStack.active.instance.instanceNumber)
+        val newStack = navigator.navigate(oldStack = oldStack, transformer = { it.dropLast(1) })
+
+        assertSame(oldStack.backStack[0].asCreated().instance, newStack.backStack[0].asCreated().instance)
+        assertSame(oldStack.backStack[1].asCreated().instance, newStack.active.instance)
     }
 
     @Test
@@ -341,7 +338,7 @@ class StackNavigatorTest {
                 transformer = { newConfigurationStack }
             )
 
-        assertEquals(newConfigurationStack, newStack.getConfigurationStack())
+        assertEquals(newConfigurationStack, newStack.configurationStack)
     }
 
     @Test
@@ -392,30 +389,33 @@ class StackNavigatorTest {
                 transformer = { newConfigurationStack }
             )
 
-        assertEquals(newConfigurationStack, newStack.getConfigurationStack())
+        assertEquals(newConfigurationStack, newStack.configurationStack)
     }
 
     @Test
     fun WHEN_navigate_to_partially_different_stack_with_new_active_component_THEN_same_old_components_not_recreated() {
         val sameConfig1 = Config()
         val sameConfig2 = Config()
 
+        val oldStack =
+            RouterStack(
+                active = activeEntry(configuration = Config()),
+                backStack = listOf(
+                    createdEntry(configuration = Config()),
+                    createdEntry(configuration = sameConfig1),
+                    createdEntry(configuration = Config()),
+                    createdEntry(configuration = sameConfig2)
+                )
+            )
+
         val newStack =
             navigator.navigate(
-                oldStack = RouterStack(
-                    active = activeEntry(configuration = Config()),
-                    backStack = listOf(
-                        createdEntry(configuration = Config()),
-                        createdEntry(configuration = sameConfig1),
-                        createdEntry(configuration = Config()),
-                        createdEntry(configuration = sameConfig2)
-                    )
-                ),
+                oldStack = oldStack,
                 transformer = { listOf(Config(), sameConfig1, sameConfig2, Config(), Config()) }
             )
 
-        assertEquals(1, (newStack.backStack[1] as RouterEntry.Created).instance.instanceNumber)
-        assertEquals(1, (newStack.backStack[2] as RouterEntry.Created).instance.instanceNumber)
+        assertSame(oldStack.backStack[1].asCreated().instance, newStack.backStack[1].asCreated().instance)
+        assertSame(oldStack.backStack[3].asCreated().instance, newStack.backStack[2].asCreated().instance)
     }
 
     @Test
@@ -439,7 +439,7 @@ class StackNavigatorTest {
                 transformer = { newConfigurationStack }
             )
 
-        assertEquals(newConfigurationStack, newStack.getConfigurationStack())
+        assertEquals(newConfigurationStack, newStack.configurationStack)
     }
 
     @Test
@@ -448,30 +448,62 @@ class StackNavigatorTest {
         val sameConfig2 = Config()
         val sameConfig3 = Config()
 
+        val oldStack =
+            RouterStack(
+                active = activeEntry(configuration = sameConfig3),
+                backStack = listOf(
+                    createdEntry(configuration = Config()),
+                    createdEntry(configuration = sameConfig1),
+                    createdEntry(configuration = Config()),
+                    createdEntry(configuration = sameConfig2)
+                )
+            )
+
         val newStack =
             navigator.navigate(
-                oldStack = RouterStack(
-                    active = activeEntry(configuration = sameConfig3),
-                    backStack = listOf(
-                        createdEntry(configuration = Config()),
-                        createdEntry(configuration = sameConfig1),
-                        createdEntry(configuration = Config()),
-                        createdEntry(configuration = sameConfig2)
-                    )
-                ),
+                oldStack = oldStack,
                 transformer = { listOf(Config(), sameConfig1, sameConfig2, Config(), sameConfig3) }
             )
 
-        assertEquals(1, (newStack.backStack[1] as RouterEntry.Created).instance.instanceNumber)
-        assertEquals(1, (newStack.backStack[2] as RouterEntry.Created).instance.instanceNumber)
-        assertEquals(1, newStack.active.instance.instanceNumber)
+        assertSame(oldStack.backStack[1].asCreated().instance, newStack.backStack[1].asCreated().instance)
+        assertSame(oldStack.backStack[3].asCreated().instance, newStack.backStack[2].asCreated().instance)
+        assertSame(oldStack.active.instance, newStack.active.instance)
+    }
+
+    @Test
+    fun WHEN_navigate_to_equal_stack_THEN_stack_not_changed() {
+        val sameConfig1 = Config()
+        val sameConfig2 = Config()
+
+        val oldStack =
+            RouterStack(
+                active = activeEntry(configuration = sameConfig1),
+                backStack = listOf(createdEntry(configuration = sameConfig2))
+            )
+
+        val newStack = navigator.navigate(oldStack = oldStack, transformer = { listOf(sameConfig2, sameConfig1) })
+
+        assertEquals(oldStack, newStack)
     }
 
-    private fun RouterStack<Config, *>.getConfigurationBackStack(): List<Config> =
-        backStack.map(RouterEntry<Config, *>::configuration)
+    @Test
+    fun WHEN_navigate_to_same_stack_THEN_stack_not_changed() {
+        val sameConfig1 = Config()
+        val sameConfig2 = Config()
 
-    private fun RouterStack<Config, *>.getConfigurationStack(): List<Config> =
-        getConfigurationBackStack() + active.configuration
+        val oldStack =
+            RouterStack(
+                active = activeEntry(configuration = sameConfig1),
+                backStack = listOf(createdEntry(configuration = sameConfig2))
+            )
+
+        val newStack = navigator.navigate(oldStack = oldStack, transformer = { it })
+
+        assertEquals(oldStack, newStack)
+    }
+
+    private fun <C : Any, T : Any> RouterEntry<C, T>.asCreated(): RouterEntry.Created<C, T> =
+        this as RouterEntry.Created<C, T>
 
     private companion object {
         private fun activeEntry(
@@ -519,29 +551,18 @@ class StackNavigatorTest {
 
     private class Config
 
-    private data class Component(
-        val instanceNumber: Int = 1
-    )
+    private class Component
 
     private class TestRouterEntryFactory : RouterEntryFactory<Config, Component> {
-        private val components = ArrayList<Pair<Config, Component>>()
-
         override fun invoke(
             configuration: Config,
             savedState: ParcelableContainer?,
             instanceKeeperDispatcher: InstanceKeeperDispatcher?
-        ): RouterEntry.Created<Config, Component> {
-            var component: Component? = components.find { it.first === configuration }?.second
-            component = component?.copy(instanceNumber = component.instanceNumber + 1) ?: Component()
-
-            components.removeAll { it.first === configuration }
-            components += configuration to component
-
-            return createdEntry(
+        ): RouterEntry.Created<Config, Component> =
+            createdEntry(
                 configuration = configuration,
-                component = component,
+                component = Component(),
                 stateKeeperDispatcher = TestStateKeeperDispatcher(savedState)
             )
-        }
     }
 }

decompose/src/commonTest/kotlin/com/arkivanov/decompose/router/TestRouter.kt

@@ -27,7 +27,10 @@ class TestRouter<C : Any>(stack: List<C>) : Router<C, Any> {
             }
         )
 
-    override fun navigate(transformer: (stack: List<C>) -> List<C>) {
-        stack = transformer(stack)
+    override fun navigate(transformer: (stack: List<C>) -> List<C>, onComplete: (newStack: List<C>, oldStack: List<C>) -> Unit) {
+        val oldStack = stack
+        val newStack = transformer(stack)
+        stack = newStack
+        onComplete(newStack, oldStack)
     }
 }

decompose/src/jsMain/kotlin/com/arkivanov/decompose/router/webhistory/DefaultWebHistoryController.kt

@@ -5,6 +5,7 @@ import com.arkivanov.decompose.router.Router
 import com.arkivanov.decompose.router.RouterState
 import com.arkivanov.decompose.router.configurations
 import com.arkivanov.decompose.router.findFirstDifferentIndex
+import com.arkivanov.decompose.router.navigate
 import com.arkivanov.decompose.router.startsWith
 import com.arkivanov.decompose.router.subscribe
 import org.w3c.dom.PopStateEvent

decompose/src/jsTest/kotlin/com/arkivanov/decompose/router/webhistory/DefaultWebHistoryControllerTest.kt

@@ -2,6 +2,7 @@ package com.arkivanov.decompose.router.webhistory
 
 import com.arkivanov.decompose.ExperimentalDecomposeApi
 import com.arkivanov.decompose.router.TestRouter
+import com.arkivanov.decompose.router.navigate
 import com.arkivanov.decompose.router.pop
 import com.arkivanov.decompose.router.push
 import com.arkivanov.essenty.parcelable.Parcelable

deps.versions.toml

@@ -1,14 +1,13 @@
 [versions]
 
-decompose = "0.5.2"
-kotlin = "1.6.10"
+decompose = "0.6.0-native-compose"
+kotlin = "1.6.20"
 essenty = "0.2.2"
-reaktive = "1.2.0"
+reaktive = "1.2.1"
 junit = "4.13.2"
-jetbrainsCompose = "1.1.0"
-jetbrainsKotlinWrappers = "0.0.1-pre.213-kotlin-1.5.10"
-jetpackCompose = "1.1.1"
-jetpackComposeCompiler = "1.1.1"
+jetbrainsCompose = "0.0.0-on-rebase-12-apr-2022-dev668"
+jetbrainsKotlinWrappers = "0.0.1-pre.325-kotlin-1.6.10"
+jetbrainsKotlinxCoroutines = "1.6.1"
 androidGradle = "7.1.0"
 androidMaterial = "1.3.0"
 androidPlay = "1.10.0"
@@ -17,7 +16,6 @@ androidxAppcompat = "1.2.0"
 androidxLifecycle = "2.3.1"
 androidxActivity = "1.3.1"
 androidxTestCore = "1.4.0"
-muirwickMuirwickComponents = "0.8.2"
 
 [libraries]
 
@@ -35,13 +33,7 @@ junit-junit = { group = "junit", name = "junit", version.ref = "junit" }
 jetbrains-compose-composeGradlePlug = { group = "org.jetbrains.compose", name = "compose-gradle-plugin", version.ref = "jetbrainsCompose" }
 jetbrains-compose-ui-uiTestJunit4 = { group = "org.jetbrains.compose.ui", name = "ui-test-junit4", version.ref = "jetbrainsCompose" }
 jetbrains-kotlinWrappers-kotlinWrappersBom = { group = "org.jetbrains.kotlin-wrappers", name = "kotlin-wrappers-bom", version.ref = "jetbrainsKotlinWrappers" }
-
-androidx-compose-compiler-compiler = { group = "androidx.compose.compiler", name = "compiler", version.ref = "jetpackCompose" }
-androidx-compose-foundation-foundation = { group = "androidx.compose.foundation", name = "foundation", version.ref = "jetpackCompose" }
-androidx-compose-material-material = { group = "androidx.compose.material", name = "material", version.ref = "jetpackCompose" }
-androidx-compose-ui-uiTestJunit4 = { group = "androidx.compose.ui", name = "ui-test-junit4", version.ref = "jetpackCompose" }
-androidx-compose-ui-uiTestManifest = { group = "androidx.compose.ui", name = "ui-test-manifest", version.ref = "jetpackCompose" }
-androidx-compose-ui-uiTooling = { group = "androidx.compose.ui", name = "ui-tooling", version.ref = "jetpackCompose" }
+jetbrains-kotlinx-kotlinxCoroutinesSwing = { group = "org.jetbrains.kotlinx", name = "kotlinx-coroutines-swing", version.ref = "jetbrainsKotlinxCoroutines" }
 
 android-gradle = { group = "com.android.tools.build", name = "gradle", version.ref = "androidGradle" }
 android-material-material = { group = "com.google.android.material", name = "material", version.ref = "androidMaterial" }
@@ -53,6 +45,3 @@ androidx-lifecycle-lifecycleCommonJava8 = { group = "androidx.lifecycle", name =
 androidx-activity-activityKtx = { group = "androidx.activity", name = "activity-ktx", version.ref = "androidxActivity" }
 androidx-activity-activityCompose = { group = "androidx.activity", name = "activity-compose", version.ref = "androidxActivity" }
 androidx-test-core = { group = "androidx.test", name = "core", version.ref = "androidxTestCore" }
-
-muirwik-muirwikComponents = { group = "com.ccfraser.muirwik", name = "muirwik-components", version.ref = "muirwickMuirwickComponents" }
-#  = { group = "", name = "", version.ref = "" }

docs/component/overview.md

@@ -36,7 +36,100 @@ class Counter(
 }
 ```
 
-When instantiating a root component we have to create `ComponentContext` manually. There is [DefaultComponentContext](https://github.com/arkivanov/Decompose/blob/master/decompose/src/commonMain/kotlin/com/arkivanov/decompose/DefaultComponentContext.kt) which is the default implementation class of the `ComponentContext`. There are also handy helper functions provided by Jetpack/JetBrains Compose extension modules.
+## Root ComponentContext
+
+When instantiating a root component, the `ComponentContext` should be created manually. There is [DefaultComponentContext](https://github.com/arkivanov/Decompose/blob/master/decompose/src/commonMain/kotlin/com/arkivanov/decompose/DefaultComponentContext.kt) which is the default implementation class of the `ComponentContext`.
+
+### Root ComponentContext in Android
+
+Decompose provides a few handy [helper functions](https://github.com/arkivanov/Decompose/blob/master/decompose/src/androidMain/kotlin/com/arkivanov/decompose/DefaultComponentContextBuilder.kt) for creating the root `ComponentContext` in Android. The preferred way is to create the root `ComponentContext` in an `Activity` or a `Fragment`.
+
+#### Root ComponentContext in Activity
+
+For this case Decompose provides `defaultComponentContext()` extension function, which can be called in scope of an `Activity`.
+
+#### Root ComponentContext in Fragment
+
+The `defaultComponentContext()` extension function can not be used in a Fragment. This is because the `Fragment` class does not implement the `OnBackPressedDispatcherOwner` interface, and so by default can't handle back button events. It is advised to use the Android-specific `DefaultComponentContext(AndroidLifecycle, SavedStateRegistry?, ViewModelStore?, OnBackPressedDispatcher?)` factory function, and supply all the arguments manually. The first three arguments (`AndroidLifecycle`, `SavedStateRegistry` and `ViewModelStore`) can be obtained directly from `Fragment`. However the last argument `OnBackPressedDispatcher` - can not. If you don't need to handle back button events in your Decompose components, then you can just ignore this argument. Otherwise, a manual solution is required.
+
+> ⚠️ Don't take any argument values from the hosting `Activity` (e.g. `requireActivity().onBackPressedDispatcher`), as it may produce memory leaks.
+
+Here is an example with using Decompose in a `DialogFragment`.
+
+```kotlin
+class MyFragment : DialogFragment() {
+    // Create custom OnBackPressedDispatcher
+    private val onBackPressedDispatcher = OnBackPressedDispatcher(::dismiss)
+
+    private lateinit var root: Root
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+
+        root =
+            Root(
+                DefaultComponentContext(
+                    lifecycle = lifecycle,
+                    savedStateRegistry = savedStateRegistry,
+                    viewModelStore = viewModelStore,
+                    onBackPressedDispatcher = onBackPressedDispatcher,
+                )
+            )
+    }
+
+    override fun onCreateDialog(savedInstanceState: Bundle?): Dialog =
+        object : Dialog(requireContext(), theme) {
+            override fun onBackPressed() {
+                onBackPressedDispatcher.onBackPressed()
+            }
+        }
+
+    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View =
+        // Start Compose here
+}
+```
+
+### Root ComponentContext in Jetpack/JetBrains Compose
+
+It is advised to not create the root `ComponentContext` (and a root component) directly in a `Composable` function. Compositions may be performed in a background thread, which may brake things. The preferred way is to create the root component outside of Compose.
+
+> ⚠️ If you can't avoid creating the root component in a `Composable` function, please make sure you use `remember`. This will prevent the root component and its `ComponentContext` from being recreated on each composition.
+
+#### Android with Compose
+
+Prefer creating the root `ComponentContext` (and a root component) before starting Compose, e.g. in an `Activity` or a `Fragment`.
+
+```kotlin
+class MainActivity : AppCompatActivity() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+
+        // Create the root component before starting Compose
+        val root = RootComponent(componentContext = defaultComponentContext())
+
+        // Start Compose
+        setContent {
+            // The rest of the code
+        }
+    }
+}
+```
+
+#### Other platforms with Compose
+
+Prefer creating the root `ComponentContext` (and a root component) before starting Compose, e.g. in directly in the `main` function.
+
+```kotlin
+fun main() {
+    // Create the root component before starting Compose
+    val root = RootComponent(componentContext = DefaultComponentContext(...))
+
+    // Start Compose
+    application {
+        // The rest of the code
+    }
+}
+```
 
 ## Child components
 

docs/extensions/compose.md

@@ -54,11 +54,40 @@ interface SomeComponent {
 }
 
 @Composable
-fun SomeUi(component: SomeComponent) {
+fun SomeContent(component: SomeComponent) {
     val models: State<Model> by component.models.subscribeAsState()
 }
 ```
 
+### Controlling the Lifecycle on Desktop
+
+When using JetBrains Compose, you can have a `LifecycleRegistry` react to changes in the window state using the `LifecycleController()` composable. This will trigger appropriate lifecycle events when the window is minimized, restored or closed.
+
+It is also possible to manually start the lifecycle using `LifecycleRegistry.resume()` when the instance is created.
+
+```kotlin
+fun main() {
+    val lifecycle = LifecycleRegistry()
+    val root = RootComponent(DefaultComponentContext(lifecycle))
+
+    // Alternative: manually start the lifecycle (no reaction to window state)
+    // lifecycle.resume()
+
+    application {
+        val windowState = rememberWindowState()
+
+        // Bind the registry to the life cycle of the window
+        LifecycleController(lifecycle, windowState)
+
+        Window(state = windowState, ...) {
+            // The rest of your content
+        }
+    }
+}
+```
+
+> ⚠️ When using Compose in desktop platforms, make sure to always use one of the methods above, or your components might not receive lifecycle events correctly.
+
 ### Navigating between Composable components
 
 The [Router](https://arkivanov.github.io/Decompose/router/overview/) provides
@@ -79,99 +108,124 @@ interface RootComponent {
     val routerState: Value<RouterState<*, Child>>
 
     sealed class Child {
-        data class Profile(val component: ProfileComponent) : Child()
-        data class Settings(val component: SettingsComponent) : Child()
+        data class Main(val component: MainComponent) : Child()
+        data class Details(val component: DetailsComponent) : Child()
     }
 }
 
 @Composable
-fun RootUi(rootComponent: RootComponent) {
+fun RootContent(rootComponent: RootComponent) {
     Children(rootComponent.routerState) {
         when (val child = it.instance) {
-            is RootComponent.Child.Profile -> ProfileUi(child.component)
-            is RootComponent.Child.Settings -> SettingsUi(child.component)
+            is RootComponent.Child.Main -> MainContent(child.component)
+            is RootComponent.Child.Details -> DetailsContent(child.component)
         }
     }
 }
 
 // Children
 
-interface ProfileComponent
+interface MainComponent
 
-interface SettingsComponent
+interface DetailsComponent
 
 @Composable
-fun ProfileUi(profileComponent: ProfileComponent) {
+fun MainContent(profileComponent: MainComponent) {
     // Omitted code
 }
 
 @Composable
-fun SettingsUi(settingsComponent: SettingsComponent) {
+fun DetailsContent(settingsComponent: DetailsComponent) {
     // Omitted code
 }
 ```
 
-### Animations
+### Animations (experimental)
 
-Decompose provides the [Child Animation API](https://github.com/arkivanov/Decompose/tree/master/extensions-compose-jetpack/src/main/java/com/arkivanov/decompose/extensions/compose/jetpack/animation/child) for Compose, as well as some predefined animation specs. To enable child animations you need to pass   the `animation` argument to the `Children` function.
+Decompose provides the [Child Animation API](https://github.com/arkivanov/Decompose/tree/master/extensions-compose-jetpack/src/main/java/com/arkivanov/decompose/extensions/compose/jetpack/animation/child) for Compose, as well as some predefined animation specs. To enable child animations you need to pass the `animation` argument to the `Children` function. There are predefined animators provided by Decompose.
 
-#### Crossfade animation
+#### Fade animation
 
 ```kotlin
 @Composable
-fun RootUi(rootComponent: RootComponent) {
+fun RootContent(rootComponent: RootComponent) {
     Children(
         routerState = rootComponent.routerState,
-        animation = crossfade()
+        animation = childAnimation(fade())
     ) {
         // Omitted code
     }
 }
 ```
 
-<img src="https://raw.githubusercontent.com/arkivanov/Decompose/master/docs/media/ComposeAnimationCrossfade.gif" width="512">
+<img src="https://raw.githubusercontent.com/arkivanov/Decompose/master/docs/media/ComposeAnimationFade.gif" width="512">
 
-#### Crossfade-Scale animation
+#### Slide animation
 
 ```kotlin
 @Composable
-fun RootUi(rootComponent: RootComponent) {
+fun RootContent(rootComponent: RootComponent) {
     Children(
         routerState = rootComponent.routerState,
-        animation = crossfadeScale()
+        animation = childAnimation(slide())
     ) {
         // Omitted code
     }
 }
 ```
 
-<img src="https://raw.githubusercontent.com/arkivanov/Decompose/master/docs/media/ComposeAnimationCrossfadeScale.gif" width="512">
+<img src="https://raw.githubusercontent.com/arkivanov/Decompose/master/docs/media/ComposeAnimationSlide.gif" width="512">
 
-#### Slide animation
+#### Combining animators
+
+It is also possible to combine animators using the `plus` operator. Please note that the order matters - the right animator is applied after the left animator.
 
 ```kotlin
 @Composable
-fun RootUi(rootComponent: RootComponent) {
+fun RootContent(rootComponent: RootComponent) {
     Children(
         routerState = rootComponent.routerState,
-        animation = slide()
+        animation = childAnimation(fade() + scale())
     ) {
         // Omitted code
     }
 }
 ```
 
-<img src="https://raw.githubusercontent.com/arkivanov/Decompose/master/docs/media/ComposeAnimationSlide.gif" width="512">
+<img src="https://raw.githubusercontent.com/arkivanov/Decompose/master/docs/media/ComposeAnimationFadeScale.gif" width="512">
+
+#### Separate animations for children
+
+Previous examples demonstrate simple cases, when all children have the same animation. But it is also possible to specify separate animations for children.
+
+```kotlin
+@Composable
+fun RootContent(rootComponent: RootComponent) {
+    Children(
+        routerState = rootComponent.routerState,
+        animation = childAnimation { child, direction ->
+            when (child.instance) {
+                is RootComponent.Child.Main -> fade() + scale()
+                is RootComponent.Child.Details -> fade() + slide()
+            }
+        }
+    ) {
+        // Omitted code
+    }
+}
+```
+
+<img src="https://raw.githubusercontent.com/arkivanov/Decompose/master/docs/media/ComposeAnimationSeparate.gif" width="512">
 
 #### Custom animations
 
-It is possible to define custom animations in two ways.
+It is also possible to define custom animations.
 
-Implementing the `ChildAnimation` manually:
+Implementing `ChildAnimation` manually. This is the most flexible low-level API. The animation block receives the current `RouterState` and animates children using the provided `content` slot.
 
 ```kotlin
 @Composable
-fun RootUi(rootComponent: RootComponent) {
+fun RootContent(rootComponent: RootComponent) {
     Children(
         routerState = rootComponent.routerState,
         animation = someAnimation()
@@ -181,27 +235,53 @@ fun RootUi(rootComponent: RootComponent) {
 }
 
 fun <C : Any, T : Any> someAnimation(): ChildAnimation<C, T> =
-    { routerState: RouterState<C, T>, childContent: ChildContent<C, T> ->
+    ChildAnimation { routerState: RouterState<C, T>,
+                     modifier: Modifier,
+                     content: @Composable (Child.Created<C, T>) -> Unit ->
         // Render each frame here
     }
 ```
 
-Implementing the `ChildAnimation` using the `childAnimation` builder function:
+Using the `childAnimation` helper function and implementing `ChildAnimator`. The `childAnimation` function takes care of tracking the `RouterState` changes. `ChildAnimator` is only responsible for manipulating the `Modifier` in the given `direction`, and calling `onFinished` at the end.
+
+```kotlin
+@Composable
+fun RootContent(rootComponent: RootComponent) {
+    Children(
+        routerState = rootComponent.routerState,
+        animation = childAnimation(someAnimator())
+    ) {
+        // Omitted code
+    }
+}
+
+fun someAnimator(): ChildAnimator =
+    ChildAnimator { direction: Direction,
+                    onFinished: () -> Unit,
+                    content: @Composable (Modifier) -> Unit ->
+        // Manipulate the Modifier in the given direction and call onFinished at the end
+    }
+```
+
+Using `childAnimation` and `childAnimator` helper functions. This is the simplest, but less powerful way. The `childAnimator` function takes care of running the animation. Its block has a very limited responsibility - to render the current frame using the provided `factor` and `direction`.
 
 ```kotlin
-fun <C : Any, T : Any> someAnimation(
-    animationSpec: FiniteAnimationSpec<Float> = defaultChildAnimationSpec,
-): ChildAnimation<C, T> =
-    childAnimation(
-        animationSpec = animationSpec
+@Composable
+fun RootContent(rootComponent: RootComponent) {
+    Children(
+        routerState = rootComponent.routerState,
+        animation = childAnimation(someAnimator())
     ) {
-        child: Child.Created<C, T>,
-        factor: Float,
-        placement: ChildPlacement,
-        direction: ChildAnimationDirection,
-        content: @Composable () -> Unit ->
-        // Render the current frame here
+        // Omitted code
+    }
+}
+
+fun someAnimator(): ChildAnimator =
+    childAnimator { factor: Float,
+                    direction: Direction,
+                    content: (Modifier) -> Unit ->
+        // Render the current frame
     }
 ```
 
-Please refer to the predefined animations for implementation examples.
+Please refer to the predefined animators (`fade`, `slide`, etc.) for implementation examples.

docs/router/navigation.md

@@ -1,15 +1,22 @@
 # Navigation
 
-## Router
+## The Router
 
-All navigation in Decompose is done through the [`Router`](https://github.com/arkivanov/Decompose/blob/master/decompose/src/commonMain/kotlin/com/arkivanov/decompose/router/Router.kt) interface. It has one function `navigate(transformer: (List<C>) -> List<C>)` which transforms the current stack of configurations into a new one by the provided `transformer` function. The stack is represented as `List`, where the last element is the top of the stack, and the first element is the bottom of the stack.
+All navigation in Decompose is done through the [`Router`](https://github.com/arkivanov/Decompose/blob/master/decompose/src/commonMain/kotlin/com/arkivanov/decompose/router/Router.kt) interface. There is `navigate(transformer: (List<C>) -> List<C>, onComplete: (newStack: List<C>, oldStack: List<C>) -> Unit)` method with two arguments:
 
-> ⚠️ The returned stack must not be empty.
+- `transformer` - converts the current stack of configurations into a new one. The stack is represented as `List`, where the last element is the top of the stack, and the first element is the bottom of the stack.
+- `onComplete` - called when navigation is finished.
 
-The navigation is always performed synchronously during the `navigate` method call. The only exception to this rule is when the `navigate` method is called recursively. All recursive invocations are queued and performed one by one once the current navigation is finished.
+There is also `navigate(transformer: (stack: List<C>) -> List<C>)` extension function for convenience, without the `onComplete` callback.
+
+> ⚠️ The configuration stack returned by the `transformer` function must not be empty.
+
+### The navigation process
 
 During the navigation process, the `Router` compares the new stack of configurations with the previous one. The `Router` ensures that all removed components are destroyed, and that there is only one component resumed at a time - the top one. All components in the back stack are always either stopped or destroyed.
 
+The `Router` usually performs the navigation synchronously, which means that by the time the `navigate` method returns, the navigation is finished and all component lifecycles are moved into required states. However the navigation is performed asynchronously in case of recursive invocations - e.g. `pop` is called from `onResume` lifecycle callback of a component being pushed. All recursive invocations are queued and performed one by one once the current navigation is finished.
+
 ## Router extension functions
 
 There are `Router` [extension functions](https://github.com/arkivanov/Decompose/blob/master/decompose/src/commonMain/kotlin/com/arkivanov/decompose/router/RouterExt.kt) that provide conveniences for navigating, some of which were already used in the [router overview example](../overview/#routing-example).
@@ -46,6 +53,13 @@ Pops the latest configuration at the top of the stack.
 router.pop()
 ```
 
+```kotlin
+router.pop { isSuccess ->
+    // Called when the navigation is finished.
+    // isSuccess - `true` if the stack size was greater than 1 and a component was popped, `false` otherwise.
+}
+```
+
 ![](../media/RouterPop.png)
 
 ### Pop While

extensions-compose-jetbrains/api/android/extensions-compose-jetbrains.api

@@ -6,68 +6,72 @@ public final class com/arkivanov/decompose/extensions/compose/jetbrains/BuildCon
 }
 
 public final class com/arkivanov/decompose/extensions/compose/jetbrains/ChildrenKt {
-	public static final fun Children (Lcom/arkivanov/decompose/router/RouterState;Landroidx/compose/ui/Modifier;Lkotlin/jvm/functions/Function5;Lkotlin/jvm/functions/Function3;Landroidx/compose/runtime/Composer;II)V
-	public static final fun Children (Lcom/arkivanov/decompose/value/Value;Landroidx/compose/ui/Modifier;Lkotlin/jvm/functions/Function5;Lkotlin/jvm/functions/Function3;Landroidx/compose/runtime/Composer;II)V
-}
-
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/RootComponentBuilderKt {
-	public static final fun rememberRootComponent (Landroidx/savedstate/SavedStateRegistry;Landroidx/lifecycle/ViewModelStore;Landroidx/activity/OnBackPressedDispatcher;Landroidx/lifecycle/Lifecycle;Lkotlin/jvm/functions/Function1;Landroidx/compose/runtime/Composer;II)Ljava/lang/Object;
-	public static final fun rememberRootComponent (Landroidx/savedstate/SavedStateRegistryOwner;Lkotlin/jvm/functions/Function1;Landroidx/compose/runtime/Composer;I)Ljava/lang/Object;
+	public static final fun Children (Lcom/arkivanov/decompose/router/RouterState;Landroidx/compose/ui/Modifier;Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimation;Lkotlin/jvm/functions/Function3;Landroidx/compose/runtime/Composer;II)V
+	public static final fun Children (Lcom/arkivanov/decompose/value/Value;Landroidx/compose/ui/Modifier;Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimation;Lkotlin/jvm/functions/Function3;Landroidx/compose/runtime/Composer;II)V
 }
 
 public final class com/arkivanov/decompose/extensions/compose/jetbrains/SubscribeAsStateKt {
 	public static final fun subscribeAsState (Lcom/arkivanov/decompose/value/Value;Landroidx/compose/runtime/Composer;I)Landroidx/compose/runtime/State;
 }
 
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/ValueComposableKt {
-	public static final fun asState (Lcom/arkivanov/decompose/value/Value;Landroidx/compose/runtime/Composer;I)Landroidx/compose/runtime/State;
+public abstract interface class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimation {
+	public abstract fun invoke (Lcom/arkivanov/decompose/router/RouterState;Landroidx/compose/ui/Modifier;Lkotlin/jvm/functions/Function3;Landroidx/compose/runtime/Composer;I)V
 }
 
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimationDirection : java/lang/Enum {
-	public static final field ENTER Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimationDirection;
-	public static final field EXIT Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimationDirection;
-	public static fun valueOf (Ljava/lang/String;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimationDirection;
-	public static fun values ()[Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimationDirection;
+public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimationKt {
+	public static final fun ChildAnimation (Lkotlin/jvm/functions/Function5;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimation;
+	public static final fun childAnimation (Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimation;
+	public static final fun childAnimation (Lkotlin/jvm/functions/Function2;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimation;
+	public static synthetic fun childAnimation$default (Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;ILjava/lang/Object;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimation;
 }
 
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimationKt {
-	public static final fun childAnimation (Landroidx/compose/animation/core/FiniteAnimationSpec;Lkotlin/jvm/functions/Function7;)Lkotlin/jvm/functions/Function5;
-	public static synthetic fun childAnimation$default (Landroidx/compose/animation/core/FiniteAnimationSpec;Lkotlin/jvm/functions/Function7;ILjava/lang/Object;)Lkotlin/jvm/functions/Function5;
+public abstract interface class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator {
+	public abstract fun invoke (Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;Lkotlin/jvm/functions/Function0;Lkotlin/jvm/functions/Function3;Landroidx/compose/runtime/Composer;I)V
 }
 
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildPlacement : java/lang/Enum {
-	public static final field BACK Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildPlacement;
-	public static final field FRONT Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildPlacement;
-	public static fun valueOf (Ljava/lang/String;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildPlacement;
-	public static fun values ()[Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildPlacement;
+public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimatorKt {
+	public static final fun ChildAnimator (Lkotlin/jvm/functions/Function5;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
+	public static final fun childAnimator (Landroidx/compose/animation/core/FiniteAnimationSpec;Lkotlin/jvm/functions/Function5;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
+	public static synthetic fun childAnimator$default (Landroidx/compose/animation/core/FiniteAnimationSpec;Lkotlin/jvm/functions/Function5;ILjava/lang/Object;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
+	public static final fun plus (Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
 }
 
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ComposableSingletons$EmptyChildAnimationKt {
-	public static final field INSTANCE Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ComposableSingletons$EmptyChildAnimationKt;
+public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ComposableSingletons$FadeKt {
+	public static final field INSTANCE Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ComposableSingletons$FadeKt;
 	public static field lambda-1 Lkotlin/jvm/functions/Function5;
 	public fun <init> ()V
 	public final fun getLambda-1$extensions_compose_jetbrains_release ()Lkotlin/jvm/functions/Function5;
 }
 
 public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ComposableSingletons$SlideKt {
 	public static final field INSTANCE Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ComposableSingletons$SlideKt;
-	public static field lambda-1 Lkotlin/jvm/functions/Function7;
+	public static field lambda-1 Lkotlin/jvm/functions/Function5;
 	public fun <init> ()V
-	public final fun getLambda-1$extensions_compose_jetbrains_release ()Lkotlin/jvm/functions/Function7;
+	public final fun getLambda-1$extensions_compose_jetbrains_release ()Lkotlin/jvm/functions/Function5;
+}
+
+public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction : java/lang/Enum {
+	public static final field ENTER_BACK Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;
+	public static final field ENTER_FRONT Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;
+	public static final field EXIT_BACK Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;
+	public static final field EXIT_FRONT Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;
+	public static final field IDLE Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;
+	public static fun valueOf (Ljava/lang/String;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;
+	public static fun values ()[Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;
 }
 
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/CrossfadeKt {
-	public static final fun crossfade (Landroidx/compose/animation/core/FiniteAnimationSpec;)Lkotlin/jvm/functions/Function5;
-	public static synthetic fun crossfade$default (Landroidx/compose/animation/core/FiniteAnimationSpec;ILjava/lang/Object;)Lkotlin/jvm/functions/Function5;
+public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/FadeKt {
+	public static final fun fade (Landroidx/compose/animation/core/FiniteAnimationSpec;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
+	public static synthetic fun fade$default (Landroidx/compose/animation/core/FiniteAnimationSpec;ILjava/lang/Object;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
 }
 
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/CrossfadeScaleKt {
-	public static final fun crossfadeScale (Landroidx/compose/animation/core/FiniteAnimationSpec;FF)Lkotlin/jvm/functions/Function5;
-	public static synthetic fun crossfadeScale$default (Landroidx/compose/animation/core/FiniteAnimationSpec;FFILjava/lang/Object;)Lkotlin/jvm/functions/Function5;
+public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ScaleKt {
+	public static final fun scale (Landroidx/compose/animation/core/FiniteAnimationSpec;FF)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
+	public static synthetic fun scale$default (Landroidx/compose/animation/core/FiniteAnimationSpec;FFILjava/lang/Object;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
 }
 
 public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/SlideKt {
-	public static final fun slide (Landroidx/compose/animation/core/FiniteAnimationSpec;)Lkotlin/jvm/functions/Function5;
-	public static synthetic fun slide$default (Landroidx/compose/animation/core/FiniteAnimationSpec;ILjava/lang/Object;)Lkotlin/jvm/functions/Function5;
+	public static final fun slide (Landroidx/compose/animation/core/FiniteAnimationSpec;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
+	public static synthetic fun slide$default (Landroidx/compose/animation/core/FiniteAnimationSpec;ILjava/lang/Object;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
 }
 

extensions-compose-jetbrains/api/jvm/extensions-compose-jetbrains.api

@@ -1,66 +1,71 @@
 public final class com/arkivanov/decompose/extensions/compose/jetbrains/ChildrenKt {
-	public static final fun Children (Lcom/arkivanov/decompose/router/RouterState;Landroidx/compose/ui/Modifier;Lkotlin/jvm/functions/Function5;Lkotlin/jvm/functions/Function3;Landroidx/compose/runtime/Composer;II)V
-	public static final fun Children (Lcom/arkivanov/decompose/value/Value;Landroidx/compose/ui/Modifier;Lkotlin/jvm/functions/Function5;Lkotlin/jvm/functions/Function3;Landroidx/compose/runtime/Composer;II)V
-}
-
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/RootComponentBuilderKt {
-	public static final fun rememberRootComponent (Lcom/arkivanov/essenty/lifecycle/Lifecycle;Lcom/arkivanov/essenty/statekeeper/StateKeeper;Lcom/arkivanov/essenty/instancekeeper/InstanceKeeper;Lcom/arkivanov/essenty/backpressed/BackPressedDispatcher;Lkotlin/jvm/functions/Function1;Landroidx/compose/runtime/Composer;II)Ljava/lang/Object;
+	public static final fun Children (Lcom/arkivanov/decompose/router/RouterState;Landroidx/compose/ui/Modifier;Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimation;Lkotlin/jvm/functions/Function3;Landroidx/compose/runtime/Composer;II)V
+	public static final fun Children (Lcom/arkivanov/decompose/value/Value;Landroidx/compose/ui/Modifier;Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimation;Lkotlin/jvm/functions/Function3;Landroidx/compose/runtime/Composer;II)V
 }
 
 public final class com/arkivanov/decompose/extensions/compose/jetbrains/SubscribeAsStateKt {
 	public static final fun subscribeAsState (Lcom/arkivanov/decompose/value/Value;Landroidx/compose/runtime/Composer;I)Landroidx/compose/runtime/State;
 }
 
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/ValueComposableKt {
-	public static final fun asState (Lcom/arkivanov/decompose/value/Value;Landroidx/compose/runtime/Composer;I)Landroidx/compose/runtime/State;
+public abstract interface class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimation {
+	public abstract fun invoke (Lcom/arkivanov/decompose/router/RouterState;Landroidx/compose/ui/Modifier;Lkotlin/jvm/functions/Function3;Landroidx/compose/runtime/Composer;I)V
 }
 
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimationDirection : java/lang/Enum {
-	public static final field ENTER Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimationDirection;
-	public static final field EXIT Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimationDirection;
-	public static fun valueOf (Ljava/lang/String;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimationDirection;
-	public static fun values ()[Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimationDirection;
+public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimationKt {
+	public static final fun ChildAnimation (Lkotlin/jvm/functions/Function5;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimation;
+	public static final fun childAnimation (Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimation;
+	public static final fun childAnimation (Lkotlin/jvm/functions/Function2;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimation;
+	public static synthetic fun childAnimation$default (Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;ILjava/lang/Object;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimation;
 }
 
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimationKt {
-	public static final fun childAnimation (Landroidx/compose/animation/core/FiniteAnimationSpec;Lkotlin/jvm/functions/Function7;)Lkotlin/jvm/functions/Function5;
-	public static synthetic fun childAnimation$default (Landroidx/compose/animation/core/FiniteAnimationSpec;Lkotlin/jvm/functions/Function7;ILjava/lang/Object;)Lkotlin/jvm/functions/Function5;
+public abstract interface class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator {
+	public abstract fun invoke (Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;Lkotlin/jvm/functions/Function0;Lkotlin/jvm/functions/Function3;Landroidx/compose/runtime/Composer;I)V
 }
 
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildPlacement : java/lang/Enum {
-	public static final field BACK Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildPlacement;
-	public static final field FRONT Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildPlacement;
-	public static fun valueOf (Ljava/lang/String;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildPlacement;
-	public static fun values ()[Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildPlacement;
+public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimatorKt {
+	public static final fun ChildAnimator (Lkotlin/jvm/functions/Function5;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
+	public static final fun childAnimator (Landroidx/compose/animation/core/FiniteAnimationSpec;Lkotlin/jvm/functions/Function5;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
+	public static synthetic fun childAnimator$default (Landroidx/compose/animation/core/FiniteAnimationSpec;Lkotlin/jvm/functions/Function5;ILjava/lang/Object;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
+	public static final fun plus (Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
 }
 
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ComposableSingletons$EmptyChildAnimationKt {
-	public static final field INSTANCE Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ComposableSingletons$EmptyChildAnimationKt;
+public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ComposableSingletons$FadeKt {
+	public static final field INSTANCE Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ComposableSingletons$FadeKt;
 	public static field lambda-1 Lkotlin/jvm/functions/Function5;
 	public fun <init> ()V
 	public final fun getLambda-1$extensions_compose_jetbrains ()Lkotlin/jvm/functions/Function5;
 }
 
 public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ComposableSingletons$SlideKt {
 	public static final field INSTANCE Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ComposableSingletons$SlideKt;
-	public static field lambda-1 Lkotlin/jvm/functions/Function7;
+	public static field lambda-1 Lkotlin/jvm/functions/Function5;
 	public fun <init> ()V
-	public final fun getLambda-1$extensions_compose_jetbrains ()Lkotlin/jvm/functions/Function7;
+	public final fun getLambda-1$extensions_compose_jetbrains ()Lkotlin/jvm/functions/Function5;
+}
+
+public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction : java/lang/Enum {
+	public static final field ENTER_BACK Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;
+	public static final field ENTER_FRONT Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;
+	public static final field EXIT_BACK Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;
+	public static final field EXIT_FRONT Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;
+	public static final field IDLE Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;
+	public static fun valueOf (Ljava/lang/String;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;
+	public static fun values ()[Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction;
 }
 
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/CrossfadeKt {
-	public static final fun crossfade (Landroidx/compose/animation/core/FiniteAnimationSpec;)Lkotlin/jvm/functions/Function5;
-	public static synthetic fun crossfade$default (Landroidx/compose/animation/core/FiniteAnimationSpec;ILjava/lang/Object;)Lkotlin/jvm/functions/Function5;
+public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/FadeKt {
+	public static final fun fade (Landroidx/compose/animation/core/FiniteAnimationSpec;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
+	public static synthetic fun fade$default (Landroidx/compose/animation/core/FiniteAnimationSpec;ILjava/lang/Object;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
 }
 
-public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/CrossfadeScaleKt {
-	public static final fun crossfadeScale (Landroidx/compose/animation/core/FiniteAnimationSpec;FF)Lkotlin/jvm/functions/Function5;
-	public static synthetic fun crossfadeScale$default (Landroidx/compose/animation/core/FiniteAnimationSpec;FFILjava/lang/Object;)Lkotlin/jvm/functions/Function5;
+public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ScaleKt {
+	public static final fun scale (Landroidx/compose/animation/core/FiniteAnimationSpec;FF)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
+	public static synthetic fun scale$default (Landroidx/compose/animation/core/FiniteAnimationSpec;FFILjava/lang/Object;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
 }
 
 public final class com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/SlideKt {
-	public static final fun slide (Landroidx/compose/animation/core/FiniteAnimationSpec;)Lkotlin/jvm/functions/Function5;
-	public static synthetic fun slide$default (Landroidx/compose/animation/core/FiniteAnimationSpec;ILjava/lang/Object;)Lkotlin/jvm/functions/Function5;
+	public static final fun slide (Landroidx/compose/animation/core/FiniteAnimationSpec;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
+	public static synthetic fun slide$default (Landroidx/compose/animation/core/FiniteAnimationSpec;ILjava/lang/Object;)Lcom/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator;
 }
 
 public final class com/arkivanov/decompose/extensions/compose/jetbrains/lifecycle/LifecycleControllerKt {

extensions-compose-jetbrains/build.gradle.kts

@@ -8,7 +8,13 @@ plugins {
 }
 
 setupMultiplatform {
-    targets(Target.Android, Target.Jvm)
+    targets(
+        Target.Android,
+        Target.Jvm,
+        Target.MacOs(),
+        Target.Ios(isAppleSiliconEnabled = false),
+    )
+
     publications()
     binaryCompatibilityValidator()
 }
@@ -31,6 +37,7 @@ kotlin {
         named("jvmTest") {
             dependencies {
                 implementation(deps.jetbrains.compose.ui.uiTestJunit4)
+                implementation(deps.jetbrains.kotlinx.kotlinxCoroutinesSwing)
                 implementation(deps.junit.junit)
                 implementation(compose.desktop.currentOs)
             }

extensions-compose-jetbrains/src/commonMain/kotlin/com/arkivanov/decompose/extensions/compose/jetbrains/Children.kt

@@ -7,13 +7,15 @@ import androidx.compose.runtime.saveable.SaveableStateHolder
 import androidx.compose.runtime.saveable.rememberSaveableStateHolder
 import androidx.compose.ui.Modifier
 import com.arkivanov.decompose.Child
+import com.arkivanov.decompose.ExperimentalDecomposeApi
 import com.arkivanov.decompose.extensions.compose.jetbrains.animation.child.ChildAnimation
 import com.arkivanov.decompose.extensions.compose.jetbrains.animation.child.emptyChildAnimation
 import com.arkivanov.decompose.router.RouterState
 import com.arkivanov.decompose.value.Value
 
 typealias ChildContent<C, T> = @Composable (child: Child.Created<C, T>) -> Unit
 
+@OptIn(ExperimentalDecomposeApi::class)
 @Composable
 fun <C : Any, T : Any> Children(
     routerState: RouterState<C, T>,
@@ -32,6 +34,7 @@ fun <C : Any, T : Any> Children(
     }
 }
 
+@OptIn(ExperimentalDecomposeApi::class)
 @Composable
 fun <C : Any, T : Any> Children(
     routerState: Value<RouterState<C, T>>,

extensions-compose-jetbrains/src/commonMain/kotlin/com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimation.kt

@@ -2,135 +2,62 @@
 
 package com.arkivanov.decompose.extensions.compose.jetbrains.animation.child
 
-import androidx.compose.animation.core.AnimationState
-import androidx.compose.animation.core.FiniteAnimationSpec
-import androidx.compose.animation.core.animateTo
-import androidx.compose.animation.core.isFinished
-import androidx.compose.animation.core.tween
-import androidx.compose.foundation.layout.Box
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.LaunchedEffect
-import androidx.compose.runtime.getValue
-import androidx.compose.runtime.key
-import androidx.compose.runtime.mutableStateOf
-import androidx.compose.runtime.remember
-import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
 import com.arkivanov.decompose.Child
 import com.arkivanov.decompose.ExperimentalDecomposeApi
-import com.arkivanov.decompose.extensions.compose.jetbrains.ChildContent
-
-internal val defaultChildAnimationSpec: FiniteAnimationSpec<Float> = tween()
+import com.arkivanov.decompose.router.RouterState
 
 /**
- * A handy API for the [Children][com.arkivanov.decompose.extensions.compose.jetbrains.Children] animations
- *
- * @param animationSpec a [FiniteAnimationSpec] to configure the animation
- * @param animator see [ChildAnimator] for details
+ * Tracks the [RouterState] changes and animates between child widget.
  */
 @ExperimentalDecomposeApi
-fun <C : Any, T : Any> childAnimation(
-    animationSpec: FiniteAnimationSpec<Float> = defaultChildAnimationSpec,
-    animator: ChildAnimator<C, T>
-): ChildAnimation<C, T> =
-    { routerState, modifier, content ->
-        ChildAnimationImpl(
-            targetPage = Page(routerState.activeChild, routerState.backStack.size),
-            modifier = modifier,
-            animationSpec = animationSpec,
-            animator = animator,
-            content = content
-        )
-    }
-
-@Suppress("TransitionPropertiesLabel")
-@Composable
-private fun <C : Any, T : Any> ChildAnimationImpl(
-    targetPage: Page<C, T>,
-    modifier: Modifier,
-    animationSpec: FiniteAnimationSpec<Float>,
-    animator: ChildAnimator<C, T>,
-    content: ChildContent<C, T>,
-) {
-    var pages: Pages<C, T> by remember { mutableStateOf(Pages(target = targetPage)) }
-    if (targetPage.configuration != pages.target.configuration) {
-        pages = Pages(target = targetPage, previous = pages.target)
-    }
-
-    val new = pages.target
-    val old = pages.previous
-
-    val animationState = remember(new.configuration) { AnimationState(if (old == null) 1F else 0F) }
+interface ChildAnimation<C : Any, T : Any> {
 
-    LaunchedEffect(new.configuration) {
-        animationState.animateTo(
-            targetValue = 1F,
-            animationSpec = animationSpec,
-            sequentialAnimation = !animationState.isFinished
-        )
-
-        pages = Pages(target = pages.target)
-    }
-
-    val items = rememberAnimationItems(targetPage = new, previousPage = old)
-
-    Box(modifier = modifier) {
-        items.forEach { item ->
-            key(item.page.child.configuration) {
-                animator(
-                    item.page.child,
-                    when (item.direction) {
-                        ChildAnimationDirection.ENTER -> animationState.value
-                        ChildAnimationDirection.EXIT -> 1F - animationState.value
-                    },
-                    item.placement,
-                    item.direction
-                ) {
-                    content(item.page.child)
-                }
-            }
-        }
-    }
+    @Composable
+    operator fun invoke(state: RouterState<C, T>, modifier: Modifier, content: @Composable (child: Child.Created<C, T>) -> Unit)
 }
 
-@Composable
-private fun <C : Any, T : Any> rememberAnimationItems(
-    targetPage: Page<C, T>,
-    previousPage: Page<C, T>?
-): List<AnimationItem<C, T>> =
-    remember(targetPage.configuration, previousPage?.configuration) {
-        when {
-            previousPage == null ->
-                listOf(AnimationItem(targetPage, ChildPlacement.BACK, ChildAnimationDirection.ENTER))
-
-            targetPage.index >= previousPage.index ->
-                listOf(
-                    AnimationItem(previousPage, ChildPlacement.BACK, ChildAnimationDirection.EXIT),
-                    AnimationItem(targetPage, ChildPlacement.FRONT, ChildAnimationDirection.ENTER),
-                )
-
-            else ->
-                listOf(
-                    AnimationItem(targetPage, ChildPlacement.BACK, ChildAnimationDirection.ENTER),
-                    AnimationItem(previousPage, ChildPlacement.FRONT, ChildAnimationDirection.EXIT),
-                )
+/**
+ * Factory function for [ChildAnimation] while `fun interface` with a `@Composable` function
+ * is not supported - [b/221488059](https://issuetracker.google.com/issues/221488059).
+ */
+@Suppress("FunctionName") // Factory function
+@ExperimentalDecomposeApi
+inline fun <C : Any, T : Any> ChildAnimation(
+    crossinline content: @Composable (
+        state: RouterState<C, T>,
+        modifier: Modifier,
+        content: @Composable (child: Child.Created<C, T>) -> Unit
+    ) -> Unit
+): ChildAnimation<C, T> =
+    object : ChildAnimation<C, T> {
+        @Composable
+        override operator fun invoke(
+            state: RouterState<C, T>,
+            modifier: Modifier,
+            content: @Composable (child: Child.Created<C, T>) -> Unit
+        ) {
+            content(state, modifier, content)
         }
     }
 
-private class Page<out C : Any, out T : Any>(
-    val child: Child.Created<C, T>,
-    val index: Int,
-) {
-    val configuration: C = child.configuration
-}
-
-private class Pages<out C : Any, out T : Any>(
-    val target: Page<C, T>,
-    val previous: Page<C, T>? = null,
-)
+/**
+ * Creates an implementation of [ChildAnimation] that allows different [ChildAnimator]s.
+ *
+ * @param selector provides a [ChildAnimator] for [Child] and [Direction].
+ */
+@ExperimentalDecomposeApi
+fun <C : Any, T : Any> childAnimation(
+    selector: (child: Child.Created<C, T>, direction: Direction) -> ChildAnimator
+): ChildAnimation<C, T> =
+    DefaultChildAnimation(selector)
 
-private class AnimationItem<out C : Any, out T : Any>(
-    val page: Page<C, T>,
-    val placement: ChildPlacement,
-    val direction: ChildAnimationDirection,
-)
+/**
+ * Creates an implementation of [ChildAnimation] with the provided [ChildAnimator].
+ *
+ * @param animator a [ChildAnimator] to be used for animation, default is [fade].
+ */
+@ExperimentalDecomposeApi
+fun <C : Any, T : Any> childAnimation(animator: ChildAnimator = fade()): ChildAnimation<C, T> =
+    childAnimation { _, _ -> animator }

extensions-compose-jetbrains/src/commonMain/kotlin/com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/ChildAnimator.kt

@@ -0,0 +1,89 @@
+package com.arkivanov.decompose.extensions.compose.jetbrains.animation.child
+
+import androidx.compose.animation.core.FiniteAnimationSpec
+import androidx.compose.animation.core.tween
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Modifier
+import com.arkivanov.decompose.ExperimentalDecomposeApi
+
+/**
+ * Animates a child widget in the given [Direction].
+ */
+@ExperimentalDecomposeApi
+interface ChildAnimator {
+
+    /**
+     * Animates the [content] in the given [Direction], and calls [onFinished] at the end.
+     */
+    @Composable
+    operator fun invoke(direction: Direction, onFinished: () -> Unit, content: @Composable (Modifier) -> Unit)
+}
+
+/**
+ * Factory function for [ChildAnimator] while `fun interface` with a `@Composable` function
+ * is not supported - [b/221488059](https://issuetracker.google.com/issues/221488059).
+ */
+@ExperimentalDecomposeApi
+inline fun ChildAnimator(
+    crossinline content: @Composable (Direction, onFinished: () -> Unit, content: @Composable (Modifier) -> Unit) -> Unit
+): ChildAnimator =
+    object : ChildAnimator {
+        @Composable
+        override operator fun invoke(direction: Direction, onFinished: () -> Unit, content: @Composable (Modifier) -> Unit) {
+            content(direction, onFinished, content)
+        }
+    }
+
+/**
+ * Creates an implementation of [ChildAnimator] with a convenient frame-by-frame rendering.
+ *
+ * @param animationSpec a [FiniteAnimationSpec] to configure the animation.
+ * @param frame renders the `content` using the provided `factor` and [Direction]. Called for every animation frame.
+ * The `factor` argument changes as follows:
+ * - Always 0F for [Direction.IDLE]
+ * - From 1F to 0F for [Direction.ENTER_FRONT]
+ * - From 0F to 1F for [Direction.EXIT_FRONT]
+ * - From -1F to 0F for [Direction.ENTER_BACK]
+ * - From 0F to -1F for [Direction.EXIT_BACK]
+ */
+@ExperimentalDecomposeApi
+fun childAnimator(
+    animationSpec: FiniteAnimationSpec<Float> = tween(),
+    frame: @Composable (factor: Float, direction: Direction, content: @Composable (Modifier) -> Unit) -> Unit
+): ChildAnimator =
+    DefaultChildAnimator(
+        animationSpec = animationSpec,
+        frame = frame
+    )
+
+/**
+ * Combines (merges) the receiver [ChildAnimator] with the [other] [ChildAnimator].
+ */
+@ExperimentalDecomposeApi
+operator fun ChildAnimator.plus(other: ChildAnimator): ChildAnimator =
+    ChildAnimator { direction, onFinished, content ->
+        val finished = remember(direction) { BooleanArray(2) }
+
+        this(
+            direction = direction,
+            onFinished = {
+                finished[0] = true
+                if (finished.all { it }) {
+                    onFinished()
+                }
+            },
+        ) { thisModifier ->
+            other(
+                direction = direction,
+                onFinished = {
+                    finished[1] = true
+                    if (finished.all { it }) {
+                        onFinished()
+                    }
+                },
+            ) { otherModifier ->
+                content(thisModifier.then(otherModifier))
+            }
+        }
+    }

extensions-compose-jetbrains/src/commonMain/kotlin/com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/DefaultChildAnimation.kt

@@ -0,0 +1,113 @@
+@file:OptIn(ExperimentalDecomposeApi::class)
+
+package com.arkivanov.decompose.extensions.compose.jetbrains.animation.child
+
+import androidx.compose.foundation.layout.Box
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.key
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.input.pointer.consumeAllChanges
+import androidx.compose.ui.input.pointer.pointerInput
+import com.arkivanov.decompose.Child
+import com.arkivanov.decompose.ExperimentalDecomposeApi
+import com.arkivanov.decompose.router.RouterState
+
+@ExperimentalDecomposeApi
+internal class DefaultChildAnimation<C : Any, T : Any>(
+    private val selector: (child: Child.Created<C, T>, direction: Direction) -> ChildAnimator
+) : ChildAnimation<C, T> {
+
+    @Composable
+    override operator fun invoke(state: RouterState<C, T>, modifier: Modifier, content: @Composable (child: Child.Created<C, T>) -> Unit) {
+        var activePage by remember { mutableStateOf(state.activePage()) }
+        var items by remember { mutableStateOf(getAnimationItems(newPage = activePage, oldPage = null)) }
+
+        if (state.activeChild.configuration != activePage.child.configuration) {
+            val oldPage = activePage
+            activePage = state.activePage()
+            items = getAnimationItems(newPage = activePage, oldPage = oldPage)
+        }
+
+        Box(modifier = modifier) {
+            items.forEach { (configuration, item) ->
+                val (child, direction) = item
+
+                key(configuration) {
+                    val animator = remember(direction) { selector(child, direction) }
+
+                    animator(
+                        direction = direction,
+                        onFinished = {
+                            when (direction) {
+                                Direction.EXIT_FRONT,
+                                Direction.EXIT_BACK -> items = items - configuration
+                                Direction.ENTER_FRONT,
+                                Direction.ENTER_BACK -> items = items + (configuration to item.copy(direction = Direction.IDLE))
+                                Direction.IDLE -> Unit
+                            }
+                        }
+                    ) { modifier ->
+                        Box(modifier = modifier) {
+                            content(child)
+                        }
+                    }
+                }
+            }
+
+            // A workaround until https://issuetracker.google.com/issues/214231672.
+            // Normally only the exiting child be disabled.
+            if (items.size > 1) {
+                Overlay(modifier = Modifier.matchParentSize())
+            }
+        }
+    }
+
+    @Composable
+    private fun Overlay(modifier: Modifier) {
+        Box(
+            modifier = modifier.pointerInput(Unit) {
+                awaitPointerEventScope {
+                    while (true) {
+                        val event = awaitPointerEvent()
+                        event.changes.forEach { it.consumeAllChanges() }
+                    }
+                }
+            }
+        )
+    }
+
+    private fun RouterState<C, T>.activePage(): Page<C, T> =
+        Page(child = activeChild, index = backStack.size)
+
+    private fun getAnimationItems(newPage: Page<C, T>, oldPage: Page<C, T>?): Map<C, AnimationItem<C, T>> =
+        when {
+            oldPage == null ->
+                listOf(AnimationItem(newPage.child, Direction.IDLE))
+
+            newPage.index >= oldPage.index ->
+                listOf(
+                    AnimationItem(oldPage.child, Direction.EXIT_BACK),
+                    AnimationItem(newPage.child, Direction.ENTER_FRONT),
+                )
+
+            else ->
+                listOf(
+                    AnimationItem(newPage.child, Direction.ENTER_BACK),
+                    AnimationItem(oldPage.child, Direction.EXIT_FRONT),
+                )
+        }.associateBy { it.child.configuration }
+
+    private data class AnimationItem<out C : Any, out T : Any>(
+        val child: Child.Created<C, T>,
+        val direction: Direction,
+    )
+
+    private class Page<out C : Any, out T : Any>(
+        val child: Child.Created<C, T>,
+        val index: Int,
+    )
+}

extensions-compose-jetbrains/src/commonMain/kotlin/com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/DefaultChildAnimator.kt

@@ -0,0 +1,45 @@
+package com.arkivanov.decompose.extensions.compose.jetbrains.animation.child
+
+import androidx.compose.animation.core.AnimationState
+import androidx.compose.animation.core.FiniteAnimationSpec
+import androidx.compose.animation.core.animateTo
+import androidx.compose.animation.core.isFinished
+import androidx.compose.animation.core.tween
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Modifier
+import com.arkivanov.decompose.ExperimentalDecomposeApi
+
+@ExperimentalDecomposeApi
+internal class DefaultChildAnimator(
+    private val animationSpec: FiniteAnimationSpec<Float> = tween(),
+    private val frame: @Composable (factor: Float, direction: Direction, content: @Composable (Modifier) -> Unit) -> Unit
+) : ChildAnimator {
+
+    @Composable
+    override operator fun invoke(direction: Direction, onFinished: () -> Unit, content: @Composable (Modifier) -> Unit) {
+        val animationState = remember(direction) { AnimationState(initialValue = if (direction == Direction.IDLE) 0F else 1F) }
+
+        LaunchedEffect(animationState) {
+            animationState.animateTo(
+                targetValue = 0F,
+                animationSpec = animationSpec,
+                sequentialAnimation = !animationState.isFinished,
+            )
+
+            onFinished()
+        }
+
+        val factor =
+            when (direction) {
+                Direction.IDLE,
+                Direction.ENTER_FRONT -> animationState.value
+                Direction.EXIT_FRONT -> 1F - animationState.value
+                Direction.ENTER_BACK -> -animationState.value
+                Direction.EXIT_BACK -> animationState.value - 1F
+            }
+
+        frame(factor, direction, content)
+    }
+}

extensions-compose-jetbrains/src/commonMain/kotlin/com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Direction.kt

@@ -0,0 +1,35 @@
+package com.arkivanov.decompose.extensions.compose.jetbrains.animation.child
+
+import com.arkivanov.decompose.ExperimentalDecomposeApi
+
+/**
+ * Represents a direction in which child widgets are animated.
+ */
+@ExperimentalDecomposeApi
+enum class Direction {
+
+    /**
+     * The child is not being animated.
+     */
+    IDLE,
+
+    /**
+     * The child is entering from the front (push).
+     */
+    ENTER_FRONT,
+
+    /**
+     * The child is exiting to the front (pop).
+     */
+    EXIT_FRONT,
+
+    /**
+     * The child is entering from the back (move from the backstack).
+     */
+    ENTER_BACK,
+
+    /**
+     * The child is exiting to the back (move to the backstack).
+     */
+    EXIT_BACK,
+}

extensions-compose-jetbrains/src/commonMain/kotlin/com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/EmptyChildAnimation.kt

@@ -1,9 +1,11 @@
 package com.arkivanov.decompose.extensions.compose.jetbrains.animation.child
 
 import androidx.compose.foundation.layout.Box
+import com.arkivanov.decompose.ExperimentalDecomposeApi
 
+@ExperimentalDecomposeApi
 internal fun <C : Any, T : Any> emptyChildAnimation(): ChildAnimation<C, T> =
-    { routerState, modifier, childContent ->
+    ChildAnimation { routerState, modifier, childContent ->
         Box(modifier = modifier) {
             childContent(routerState.activeChild)
         }

extensions-compose-jetbrains/src/commonMain/kotlin/com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Fade.kt

@@ -0,0 +1,18 @@
+package com.arkivanov.decompose.extensions.compose.jetbrains.animation.child
+
+import androidx.compose.animation.core.FiniteAnimationSpec
+import androidx.compose.animation.core.tween
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.alpha
+import com.arkivanov.decompose.ExperimentalDecomposeApi
+import kotlin.math.abs
+
+/**
+ * A simple fading animation. Appearing children's `alpha` is animated from 0.0 to 1.0.
+ * Disappearing children's `alpha` is animated from 1.0 to 0.0.
+ */
+@ExperimentalDecomposeApi
+fun fade(animationSpec: FiniteAnimationSpec<Float> = tween()): ChildAnimator =
+    childAnimator(animationSpec = animationSpec) { factor, _, content ->
+        content(Modifier.alpha(1F - abs(factor)))
+    }

extensions-compose-jetbrains/src/commonMain/kotlin/com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Scale.kt

@@ -0,0 +1,29 @@
+package com.arkivanov.decompose.extensions.compose.jetbrains.animation.child
+
+import androidx.compose.animation.core.FiniteAnimationSpec
+import androidx.compose.animation.core.tween
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.scale
+import com.arkivanov.decompose.ExperimentalDecomposeApi
+
+/**
+ * A simple scaling animation. Front (above) children are scaling from [frontFactor] to 1.0.
+ * Back (below) children are scaling from 1.0 to [backFactor].
+ */
+@ExperimentalDecomposeApi
+fun scale(
+    animationSpec: FiniteAnimationSpec<Float> = tween(),
+    frontFactor: Float = 1.15F,
+    backFactor: Float = 0.95F,
+): ChildAnimator =
+    childAnimator(animationSpec = animationSpec) { factor, _, content ->
+        content(
+            Modifier.scale(
+                if (factor >= 0F) {
+                    factor * (frontFactor - 1F) + 1F
+                } else {
+                    factor * (1F - backFactor) + 1F
+                }
+            )
+        )
+    }

extensions-compose-jetbrains/src/commonMain/kotlin/com/arkivanov/decompose/extensions/compose/jetbrains/animation/child/Slide.kt

@@ -1,30 +1,18 @@
 package com.arkivanov.decompose.extensions.compose.jetbrains.animation.child
 
 import androidx.compose.animation.core.FiniteAnimationSpec
-import androidx.compose.foundation.layout.Box
+import androidx.compose.animation.core.tween
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.layout.layout
 import com.arkivanov.decompose.ExperimentalDecomposeApi
-import com.arkivanov.decompose.extensions.compose.jetbrains.animation.child.ChildAnimation
 
 /**
- * A simple sliding animation. Children enter from the right side and exit from the left.
+ * A simple sliding animation. Children enter from one side and exit to another side.
  */
 @ExperimentalDecomposeApi
-fun <C : Any, T : Any> slide(
-    animationSpec: FiniteAnimationSpec<Float> = defaultChildAnimationSpec,
-): ChildAnimation<C, T> =
-    childAnimation(animationSpec = animationSpec) { _, factor, placement, _, content ->
-        Box(
-            modifier = Modifier.offsetXFactor(
-                factor = when (placement) {
-                    ChildPlacement.BACK -> factor - 1F
-                    ChildPlacement.FRONT -> 1F - factor
-                }
-            )
-        ) {
-            content()
-        }
+fun slide(animationSpec: FiniteAnimationSpec<Float> = tween()): ChildAnimator =
+    childAnimator(animationSpec = animationSpec) { factor, _, content ->
+        content(Modifier.offsetXFactor(factor = factor))
     }
 
 private fun Modifier.offsetXFactor(factor: Float): Modifier =