[Android] ViewGroup.dispatchAttachedToWindow crash with Fabric architecture

Description

Experiencing NullPointerException crashes in ViewGroup.dispatchAttachedToWindow when using React Native Screens with the new architecture (Fabric) enabled.

Stack Trace

      Fatal Exception: java.lang.NullPointerException: Attempt to invoke virtual method 'int android.view.View.getVisibility()' on a null object reference
   at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:3526)
   at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:3525)
   at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:3525)
   at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:3525)
   at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:3525)
   at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:3525)
   at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:3525)
   at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:3525)
   at android.view.ViewGroup.addViewInner(ViewGroup.java:5330)
   at android.view.ViewGroup.addView(ViewGroup.java:5116)
   at android.view.ViewGroup.addView(ViewGroup.java:5056)
   at androidx.fragment.app.FragmentStateManager.addViewToContainer(FragmentStateManager.java:881)
   at androidx.fragment.app.FragmentStateManager.createView(FragmentStateManager.java:565)
   at androidx.fragment.app.FragmentStateManager.moveToExpectedState(FragmentStateManager.java:272)
   at androidx.fragment.app.FragmentManager.executeOpsTogether(FragmentManager.java:1943)
   at androidx.fragment.app.FragmentManager.removeRedundantOperationsAndExecute(FragmentManager.java:1845)
   at androidx.fragment.app.FragmentManager.execSingleAction(FragmentManager.java:1751)
   at androidx.fragment.app.BackStackRecord.commitNowAllowingStateLoss(BackStackRecord.java:323)
   at com.swmansion.rnscreens.ScreenStack.onUpdate(ScreenStack.kt:262)
   at com.swmansion.rnscreens.ScreenContainer.performUpdates(ScreenContainer.kt:359)
   at com.swmansion.rnscreens.ScreenContainer.onScreenChanged$lambda$7(ScreenContainer.kt:342)
   at android.os.Handler.handleCallback(Handler.java:991)
   at android.os.Handler.dispatchMessage(Handler.java:102)
   at com.facebook.react.bridge.queue.MessageQueueThreadHandler.dispatchMessage(MessageQueueThreadHandler.kt:20)
   at android.os.Looper.loopOnce(Looper.java:232)
   at android.os.Looper.loop(Looper.java:317)
   at android.app.ActivityThread.main(ActivityThread.java:8934)
   at java.lang.reflect.Method.invoke(Method.java)
   at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:591)
   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:911)
        

Environment

• React Native version: 0.79.3
• React Native Screens version: 4.11.1
• Platform: Android
• Architecture: Fabric (New Architecture) enabled
• Device: Multiple Android devices (not device-specific)

Steps to Reproduce

1. Enable Fabric architecture in your React Native app
2. Use React Native Screens for navigation
3. Perform rapid navigation between screens
4. The crash occurs randomly during fragment transactions

Expected Behavior

Navigation should work smoothly without crashes.

Actual Behavior

App crashes with NullPointerException in ViewGroup.dispatchAttachedToWindow.

Additional Context

• This started happening after enabling the new architecture (Fabric)
• The crash is intermittent and seems to be related to race conditions
• Occurs during fragment transactions when views are being attached/detached
• Not reproducible consistently, but happens frequently enough to be a critical issue

Possible Root Cause

The issue appears to be a race condition between:

1. React Native's Fabric architecture view management
2. Android's fragment transaction system
3. React Native Screens' fragment-based navigation

When Fabric nullifies views during its async operations, the fragment transaction tries to access those views, causing the NullPointerException.

Steps to reproduce

1. Enable Fabric architecture in your React Native app
2. Use React Native Screens for navigation
3. Perform rapid navigation between screens
4. The crash occurs randomly during fragment transactions

Snack or a link to a repository

cannot share

Screens version

4.11.1

React Native version

0.79.3

Platforms

Android

JavaScript runtime

Hermes

Workflow

React Native (without Expo)

Architecture

Fabric (New Architecture)

Build type

Release mode

Device

Real device

Device model

No response

Acknowledgements

Yes

Start with the crash path through Android's ViewGroup.dispatchAttachedToWindow and the React Native Screens entries at ScreenStack.kt:262 and ScreenContainer.kt:359/342. Reproduce rapid navigation with Fabric enabled on Android and inspect the fragment transaction flow. Done means the intermittent NullPointerException no longer occurs during repeated navigation, with regression coverage if the project exposes a suitable test path.