fix(expo): recreate Android recomposer after reattach

.changeset/fuzzy-lions-recompose.md

@@ -0,0 +1,5 @@
+---
+'@clerk/expo': patch
+---
+
+Fix Android native UI components crashing before window attachment or becoming unresponsive after navigation detaches and reattaches their views.

packages/expo/android/src/main/java/expo/modules/clerk/ClerkComposeNativeViewHost.kt

@@ -18,41 +18,57 @@ import androidx.savedstate.setViewTreeSavedStateRegistryOwner
 import expo.modules.kotlin.AppContext
 import expo.modules.kotlin.views.ExpoView
 import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.SupervisorJob
 import kotlinx.coroutines.launch
 
 abstract class ClerkComposeNativeViewHost(context: Context, appContext: AppContext) : ExpoView(context, appContext) {
   protected val activity: ComponentActivity? = findActivity(context)
 
   private var recomposer: Recomposer? = null
-  private var recomposerJob: kotlinx.coroutines.Job? = null
+  private var recomposerJob: Job? = null
 
   private val composeView = ComposeView(context).also { view ->
     activity?.let { act ->
       view.setViewTreeLifecycleOwner(act)
       view.setViewTreeViewModelStoreOwner(act)
       view.setViewTreeSavedStateRegistryOwner(act)
-
-      val recomposerContext = AndroidUiDispatcher.Main
-      val newRecomposer = Recomposer(recomposerContext)
-      recomposer = newRecomposer
-      view.setParentCompositionContext(newRecomposer)
-      val scope = CoroutineScope(recomposerContext + kotlinx.coroutines.SupervisorJob())
-      recomposerJob = scope.coroutineContext[kotlinx.coroutines.Job]
-      scope.launch {
-        newRecomposer.runRecomposeAndApplyChanges()
-      }
     }
     addView(view, LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT))
   }
 
+  override fun onAttachedToWindow() {
+    super.onAttachedToWindow()
+    setupView()
+  }
+
   override fun onDetachedFromWindow() {
+    composeView.disposeComposition()
     recomposer?.cancel()
     recomposerJob?.cancel()
+    recomposer = null
+    recomposerJob = null
     onHostDetachedFromWindow()
     super.onDetachedFromWindow()
   }
 
+  private fun startRecomposer() {
+    if (activity == null || recomposerJob?.isActive == true) return
+
+    // Navigation can temporarily detach and later reattach the same native host.
+    // Always give a reattached ComposeView a live parent composition context.
+    val recomposerContext = AndroidUiDispatcher.Main
+    val newRecomposer = Recomposer(recomposerContext)
+    recomposer = newRecomposer
+    composeView.setParentCompositionContext(newRecomposer)
+    val scope = CoroutineScope(recomposerContext + SupervisorJob())
+    recomposerJob = scope.launch {
+      newRecomposer.runRecomposeAndApplyChanges()
+    }
+  }
+
   fun setupView() {
+    startRecomposer()
     composeView.setContent {
       val viewModelStoreOwner = localViewModelStoreOwner()
 

packages/expo/android/src/main/java/expo/modules/clerk/ClerkUserButtonViewModule.kt

@@ -17,11 +17,6 @@ class ClerkUserButtonNativeView(context: Context, appContext: AppContext) : Cler
     activity?.let { Clerk.attachActivity(it) }
   }
 
-  override fun onAttachedToWindow() {
-    super.onAttachedToWindow()
-    setupView()
-  }
-
   @Composable
   override fun Content() {
     Box(