fix(Android): prevent crash with InsetsObserverProxy already registered

android/src/main/java/com/swmansion/rnscreens/InsetsObserverProxy.kt

@@ -1,12 +1,15 @@
 package com.swmansion.rnscreens
 
+import android.util.Log
 import android.view.View
 import androidx.core.view.OnApplyWindowInsetsListener
 import androidx.core.view.ViewCompat
 import androidx.core.view.WindowInsetsCompat
+import com.facebook.react.bridge.LifecycleEventListener
+import com.facebook.react.bridge.ReactApplicationContext
 import java.lang.ref.WeakReference
 
-object InsetsObserverProxy : OnApplyWindowInsetsListener {
+object InsetsObserverProxy : OnApplyWindowInsetsListener, LifecycleEventListener {
     private val listeners: ArrayList<OnApplyWindowInsetsListener> = arrayListOf()
     private var eventSourceView: WeakReference<View> = WeakReference(null)
 
@@ -15,8 +18,16 @@ object InsetsObserverProxy : OnApplyWindowInsetsListener {
     // whether this observer has been initially registered.
     private var hasBeenRegistered: Boolean = false
 
+    // Mainly debug variable to log warnings in case we missed some code path regarding
+    // context lifetime handling.
+    private var isObservingContextLifetime: Boolean = false
+
     private var shouldForwardInsetsToView = true
 
+    // Allow only when we have not been registered yet or the view we're observing has been
+    // invalidated due to some lifecycle we have not observed.
+    private val allowRegistration get() = !hasBeenRegistered || eventSourceView.get() == null
+
     override fun onApplyWindowInsets(
         v: View,
         insets: WindowInsetsCompat,
@@ -34,6 +45,34 @@ object InsetsObserverProxy : OnApplyWindowInsetsListener {
         return rollingInsets
     }
 
+    // Call this method to ensure that the observer proxy is
+    // unregistered when apps is destroyed or we change activity.
+    fun registerWithContext(context: ReactApplicationContext) {
+        if (isObservingContextLifetime) {
+            Log.w(
+                "[RNScreens]",
+                "InsetObserverProxy registers on new context while it has not been invalidated on the old one. Please report this as issue at https://github.com/software-mansion/react-native-screens/issues",
+            )
+        }
+
+        isObservingContextLifetime = true
+        context.addLifecycleEventListener(this)
+    }
+
+    override fun onHostResume() = Unit
+
+    override fun onHostPause() = Unit
+
+    override fun onHostDestroy() {
+        val observedView = getObservedView()
+        if (hasBeenRegistered && observedView != null) {
+            ViewCompat.setOnApplyWindowInsetsListener(observedView, null)
+            hasBeenRegistered = false
+            eventSourceView.clear()
+        }
+        isObservingContextLifetime = false
+    }
+
     fun addOnApplyWindowInsetsListener(listener: OnApplyWindowInsetsListener) {
         listeners.add(listener)
     }
@@ -42,16 +81,17 @@ object InsetsObserverProxy : OnApplyWindowInsetsListener {
         listeners.remove(listener)
     }
 
-    fun registerOnView(view: View) {
-        if (!hasBeenRegistered) {
+    /**
+     * @return boolean whether the proxy registered as a listener on a view
+     */
+    fun registerOnView(view: View): Boolean {
+        if (allowRegistration) {
             ViewCompat.setOnApplyWindowInsetsListener(view, this)
             eventSourceView = WeakReference(view)
             hasBeenRegistered = true
-        } else if (getObservedView() != view) {
-            throw IllegalStateException(
-                "[RNScreens] Attempt to register InsetsObserverProxy on $view while it has been already registered on ${getObservedView()}",
-            )
+            return true
         }
+        return false
     }
 
     fun unregister() {

android/src/main/java/com/swmansion/rnscreens/RNScreensPackage.kt

@@ -29,6 +29,10 @@ class RNScreensPackage : TurboReactPackage() {
             screenDummyLayoutHelper = ScreenDummyLayoutHelper(reactContext)
         }
 
+        // Proxy needs to register for lifecycle events in order to unregister itself
+        // on activity restarts.
+        InsetsObserverProxy.registerWithContext(reactContext)
+
         return listOf<ViewManager<*, *>>(
             ScreenContainerViewManager(),
             ScreenViewManager(),

android/src/main/java/com/swmansion/rnscreens/bottomsheet/DimmingFragment.kt

@@ -208,7 +208,7 @@ class DimmingFragment(
     override fun onStart() {
         // This is the earliest we can access child fragment manager & present another fragment
         super.onStart()
-        insetsProxy.registerOnView(requireRootView())
+        insetsProxy.registerOnView(requireDecorView())
         presentNestedFragment()
     }
 
@@ -307,7 +307,7 @@ class DimmingFragment(
             }
     }
 
-    private fun requireRootView(): View =
+    private fun requireDecorView(): View =
         checkNotNull(screen.reactContext.currentActivity) { "[RNScreens] Attempt to access activity on detached context" }
             .window.decorView