From 378d4cc63b3b913041900b653d34d9e751dae2aa Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Enrique=20Lo=CC=81pez=20Man=CC=83as?=
 <eenriquelopez@gmail.com>
Date: Wed, 10 Jun 2026 19:28:01 +0200
Subject: [PATCH] fix: prevent ComposeUiClusterRenderer crash on fast back
 gesture with compose-ui 1.10+

Addresses issue #875: IllegalStateException "Composed into the View which
doesn't propagate ViewTreeLifecycleOwner!" when navigating back while
DefaultClusterRenderer's MarkerModifier handler is still processing.

- Add scope.isActive guards in getDescriptorForCluster and
  onBeforeClusterItemRendered so that after the Compose scope is
  cancelled (e.g. on back navigation), render callbacks fall through to
  the default super implementation instead of attempting to create new
  ComposeViews with a disposed CompositionContext.
- Set ViewTreeSavedStateRegistryOwner alongside ViewTreeLifecycleOwner on
  off-screen views for full compose-ui 1.10+ compatibility.
---
 .../compose/clustering/ClusterRenderer.kt      | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/maps-compose-utils/src/main/java/com/google/maps/android/compose/clustering/ClusterRenderer.kt b/maps-compose-utils/src/main/java/com/google/maps/android/compose/clustering/ClusterRenderer.kt
index 9d8f2342..4dfb9548 100644
--- a/maps-compose-utils/src/main/java/com/google/maps/android/compose/clustering/ClusterRenderer.kt
+++ b/maps-compose-utils/src/main/java/com/google/maps/android/compose/clustering/ClusterRenderer.kt
@@ -42,6 +42,7 @@ import com.google.maps.android.clustering.view.DefaultClusterRenderer
 import com.google.maps.android.compose.ComposeUiViewRenderer
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.android.awaitFrame
+import kotlinx.coroutines.isActive
 import kotlinx.coroutines.channels.awaitClose
 import kotlinx.coroutines.flow.callbackFlow
 import kotlinx.coroutines.flow.collectLatest
@@ -50,6 +51,10 @@ import androidx.lifecycle.Lifecycle
 import androidx.lifecycle.LifecycleOwner
 import androidx.lifecycle.LifecycleRegistry
 import androidx.lifecycle.setViewTreeLifecycleOwner
+import androidx.savedstate.SavedStateRegistry
+import androidx.savedstate.SavedStateRegistryController
+import androidx.savedstate.SavedStateRegistryOwner
+import androidx.savedstate.setViewTreeSavedStateRegistryOwner
 
 internal interface ClusterRendererItemState<T : ClusterItem> {
     val unclusteredItems: State<Set<T>>
@@ -90,6 +95,15 @@ internal class ComposeUiClusterRenderer<T : ClusterItem>(
         override val lifecycle: Lifecycle get() = lifecycleRegistry
     }
 
+    private val fakeSavedStateRegistryOwner = object : SavedStateRegistryOwner {
+        private val controller = SavedStateRegistryController.create(this).apply {
+            performAttach()
+            performRestore(null)
+        }
+        override val savedStateRegistry: SavedStateRegistry get() = controller.savedStateRegistry
+        override val lifecycle: Lifecycle get() = fakeLifecycleOwner.lifecycle
+    }
+
     override fun onClustersChanged(clusters: Set<Cluster<T>>) {
         super.onClustersChanged(clusters)
         unclusteredItems.value = clusters.filter { !shouldRenderAsCluster(it) }
@@ -149,6 +163,7 @@ internal class ComposeUiClusterRenderer<T : ClusterItem>(
             }
         )
         view.setViewTreeLifecycleOwner(fakeLifecycleOwner)
+        view.setViewTreeSavedStateRegistryOwner(fakeSavedStateRegistryOwner)
         val renderHandle = viewRendererState.value.startRenderingView(view)
         val rerenderJob = scope.launch {
             collectInvalidationsAndRerender(key, view)
@@ -212,6 +227,7 @@ internal class ComposeUiClusterRenderer<T : ClusterItem>(
     }
 
     override fun getDescriptorForCluster(cluster: Cluster<T>): BitmapDescriptor {
+        if (!scope.isActive) return super.getDescriptorForCluster(cluster)
         return if (clusterContentState.value != null) {
             val viewInfo = keysToViews.entries
                 .firstOrNull { (key, _) -> (key as? ViewKey.Cluster)?.cluster == cluster }
@@ -232,6 +248,8 @@ internal class ComposeUiClusterRenderer<T : ClusterItem>(
     override fun onBeforeClusterItemRendered(item: T, markerOptions: MarkerOptions) {
         super.onBeforeClusterItemRendered(item, markerOptions)
 
+        if (!scope.isActive) return
+
         if (clusterItemContentState.value != null) {
             val viewInfo = keysToViews.entries
                 .firstOrNull { (key, _) -> (key as? ViewKey.Item)?.item == item }