fix(Android): add custom fragment factory & modify library installation steps to prevent on-restoration crashes

Example/android/app/src/main/java/com/swmansion/rnscreens/example/MainActivity.kt

@@ -5,6 +5,7 @@ import com.facebook.react.ReactActivity
 import com.facebook.react.ReactActivityDelegate
 import com.facebook.react.defaults.DefaultNewArchitectureEntryPoint.fabricEnabled
 import com.facebook.react.defaults.DefaultReactActivityDelegate
+import com.swmansion.rnscreens.fragment.restoration.RNScreensFragmentFactory
 
 class MainActivity : ReactActivity() {
 
@@ -22,6 +23,7 @@ class MainActivity : ReactActivity() {
       DefaultReactActivityDelegate(this, mainComponentName, fabricEnabled)
 
   override fun onCreate(savedInstanceState: Bundle?) {
-    super.onCreate(null)
+    supportFragmentManager.fragmentFactory = RNScreensFragmentFactory()
+    super.onCreate(savedInstanceState)
   }
 }

FabricExample/android/app/src/main/java/com/fabricexample/MainActivity.kt

@@ -1,9 +1,11 @@
 package com.fabricexample
 
+import android.os.Bundle
 import com.facebook.react.ReactActivity
 import com.facebook.react.ReactActivityDelegate
 import com.facebook.react.defaults.DefaultNewArchitectureEntryPoint.fabricEnabled
 import com.facebook.react.defaults.DefaultReactActivityDelegate
+import com.swmansion.rnscreens.fragment.restoration.RNScreensFragmentFactory
 
 class MainActivity : ReactActivity() {
 
@@ -19,4 +21,9 @@ class MainActivity : ReactActivity() {
    */
   override fun createReactActivityDelegate(): ReactActivityDelegate =
       DefaultReactActivityDelegate(this, mainComponentName, fabricEnabled)
+
+  override fun onCreate(savedInstanceState: Bundle?) {
+    supportFragmentManager.fragmentFactory = RNScreensFragmentFactory()
+    super.onCreate(savedInstanceState)
+  }
 }

README.md

@@ -35,6 +35,7 @@ Please note that the override code should not be placed inside `MainActivityDele
 
 ```java
 import android.os.Bundle;
+import com.swmansion.rnscreens.fragment.restoration.RNScreensFragmentFactory;
 
 public class MainActivity extends ReactActivity {
 
@@ -43,7 +44,8 @@ public class MainActivity extends ReactActivity {
     //react-native-screens override
     @Override
     protected void onCreate(Bundle savedInstanceState) {
-        super.onCreate(null);
+        getSupportFragmentManager().setFragmentFactory(new RNScreensFragmentFactory());
+        super.onCreate(savedInstanceState);
     }
 
     public static class MainActivityDelegate extends ReactActivityDelegate {
@@ -59,13 +61,15 @@ public class MainActivity extends ReactActivity {
 
 ```kotlin
 import android.os.Bundle;
+import com.swmansion.rnscreens.fragment.restoration.RNScreensFragmentFactory;
 
 class MainActivity: ReactActivity() {
 
     //...code
 
     //react-native-screens override
     override fun onCreate(savedInstanceState: Bundle?) {
+      supportFragmentManager.fragmentFactory = RNScreensFragmentFactory()
       super.onCreate(null);
     }
 }

android/src/main/java/com/swmansion/rnscreens/fragment/restoration/AutoRemovingFragment.kt

@@ -0,0 +1,38 @@
+package com.swmansion.rnscreens.fragment.restoration
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.fragment.app.Fragment
+
+/**
+* This class serves as a workaround to https://github.com/software-mansion/react-native-screens/issues/17.
+*
+* This fragment, when attached to the fragment manager & its state is progressed
+* to `ON_CREATED`, attempts to detach itself from the parent fragment manager
+* as soon as possible.
+*
+* Instances of this type should be created in place of regular screen fragments
+* when Android restores fragments after activity / application restart.
+* If done so, it's behaviour can prevent duplicated fragment instances,
+* as React will render new ones on activity restart.
+*/
+class AutoRemovingFragment : Fragment() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+
+        // This is the first moment where we have access to non-null parent fragment manager,
+        // so that we can remove the fragment from the hierarchy.
+        parentFragmentManager
+            .beginTransaction()
+            .remove(this)
+            .commitAllowingStateLoss()
+    }
+
+    override fun onCreateView(
+        inflater: LayoutInflater,
+        container: ViewGroup?,
+        savedInstanceState: Bundle?,
+    ): View? = null
+}

android/src/main/java/com/swmansion/rnscreens/fragment/restoration/RNScreensFragmentFactory.kt

@@ -0,0 +1,13 @@
+package com.swmansion.rnscreens.fragment.restoration
+
+class RNScreensFragmentFactory : androidx.fragment.app.FragmentFactory() {
+    override fun instantiate(
+        classLoader: ClassLoader,
+        className: String,
+    ): androidx.fragment.app.Fragment =
+        if (className.startsWith(com.swmansion.rnscreens.BuildConfig.LIBRARY_PACKAGE_NAME)) {
+            AutoRemovingFragment()
+        } else {
+            super.instantiate(classLoader, className)
+        }
+}