Add ExtraWindowEventListener interface

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/bridge/ReactContext.java

@@ -15,6 +15,7 @@
 import android.content.Intent;
 import android.os.Bundle;
 import android.view.LayoutInflater;
+import android.view.Window;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import com.facebook.common.logging.FLog;
@@ -25,6 +26,7 @@
 import com.facebook.react.bridge.queue.MessageQueueThread;
 import com.facebook.react.bridge.queue.ReactQueueConfiguration;
 import com.facebook.react.common.LifecycleState;
+import com.facebook.react.interfaces.ExtraWindowEventListener;
 import com.facebook.react.turbomodule.core.interfaces.CallInvokerHolder;
 import java.lang.ref.WeakReference;
 import java.util.Collection;
@@ -48,6 +50,8 @@ public interface RCTDeviceEventEmitter extends JavaScriptModule {
       new CopyOnWriteArraySet<>();
   private final CopyOnWriteArraySet<ActivityEventListener> mActivityEventListeners =
       new CopyOnWriteArraySet<>();
+  private final CopyOnWriteArraySet<ExtraWindowEventListener> mExtraWindowEventListeners =
+      new CopyOnWriteArraySet<>();
   private final CopyOnWriteArraySet<WindowFocusChangeListener> mWindowFocusEventListeners =
       new CopyOnWriteArraySet<>();
   private final ScrollEndedListeners mScrollEndedListeners = new ScrollEndedListeners();
@@ -246,6 +250,14 @@ public void removeActivityEventListener(ActivityEventListener listener) {
     mActivityEventListeners.remove(listener);
   }
 
+  public void addExtraWindowEventListener(ExtraWindowEventListener listener) {
+    mExtraWindowEventListeners.add(listener);
+  }
+
+  public void removeExtraWindowEventListener(ExtraWindowEventListener listener) {
+    mExtraWindowEventListeners.remove(listener);
+  }
+
   public void addWindowFocusChangeListener(WindowFocusChangeListener listener) {
     mWindowFocusEventListeners.add(listener);
   }
@@ -356,6 +368,30 @@ public void onActivityResult(
     }
   }
 
+  @ThreadConfined(UI)
+  public void onExtraWindowCreate(Window window) {
+    UiThreadUtil.assertOnUiThread();
+    for (ExtraWindowEventListener listener : mExtraWindowEventListeners) {
+      try {
+        listener.onExtraWindowCreate(window);
+      } catch (RuntimeException e) {
+        handleException(e);
+      }
+    }
+  }
+
+  @ThreadConfined(UI)
+  public void onExtraWindowDestroy(Window window) {
+    UiThreadUtil.assertOnUiThread();
+    for (ExtraWindowEventListener listener : mExtraWindowEventListeners) {
+      try {
+        listener.onExtraWindowDestroy(window);
+      } catch (RuntimeException e) {
+        handleException(e);
+      }
+    }
+  }
+
   @ThreadConfined(UI)
   public void onWindowFocusChange(boolean hasFocus) {
     UiThreadUtil.assertOnUiThread();

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/interfaces/ExtraWindowEventListener.kt

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+package com.facebook.react.interfaces
+
+import android.view.Window
+
+/**
+ * Listener for receiving extra window creation and destruction events.
+ *
+ * This allows modules to react to new windows being added or removed, such as Dialog windows
+ * registered by Modal components. Modules like StatusBarModule can implement this interface to
+ * apply their configuration to all active windows.
+ *
+ * Third-party libraries can both implement this listener and emit window events through
+ * [ReactContext.onExtraWindowCreate] and [ReactContext.onExtraWindowDestroy].
+ */
+public interface ExtraWindowEventListener {
+
+  /** Called when a new [Window] is created (e.g. a Dialog window for a Modal). */
+  public fun onExtraWindowCreate(window: Window)
+
+  /** Called when a [Window] is destroyed (e.g. on Dialog window dismiss). */
+  public fun onExtraWindowDestroy(window: Window)
+}

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/ThemedReactContext.kt

@@ -11,6 +11,7 @@ package com.facebook.react.uimanager
 
 import android.app.Activity
 import android.content.Context
+import android.view.Window
 import com.facebook.react.bridge.Callback
 import com.facebook.react.bridge.CatalystInstance
 import com.facebook.react.bridge.JavaScriptContextHolder
@@ -22,6 +23,7 @@ import com.facebook.react.bridge.ReactContext
 import com.facebook.react.bridge.ScrollEndedListeners
 import com.facebook.react.bridge.UIManager
 import com.facebook.react.common.annotations.internal.LegacyArchitecture
+import com.facebook.react.interfaces.ExtraWindowEventListener
 import com.facebook.react.turbomodule.core.interfaces.CallInvokerHolder
 
 /**
@@ -67,6 +69,22 @@ public class ThemedReactContext(
     reactApplicationContext.removeLifecycleEventListener(listener)
   }
 
+  override fun addExtraWindowEventListener(listener: ExtraWindowEventListener) {
+    reactApplicationContext.addExtraWindowEventListener(listener)
+  }
+
+  override fun removeExtraWindowEventListener(listener: ExtraWindowEventListener) {
+    reactApplicationContext.removeExtraWindowEventListener(listener)
+  }
+
+  override fun onExtraWindowCreate(window: Window) {
+    reactApplicationContext.onExtraWindowCreate(window)
+  }
+
+  override fun onExtraWindowDestroy(window: Window) {
+    reactApplicationContext.onExtraWindowDestroy(window)
+  }
+
   override fun hasCurrentActivity(): Boolean = reactApplicationContext.hasCurrentActivity()
 
   override fun getCurrentActivity(): Activity? = reactApplicationContext.getCurrentActivity()

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/views/modal/ReactModalHostView.kt

@@ -196,6 +196,9 @@ public class ReactModalHostView(context: ThemedReactContext) :
     UiThreadUtil.assertOnUiThread()
 
     dialog?.let { nonNullDialog ->
+      nonNullDialog.window?.let { window ->
+        (context as ThemedReactContext).onExtraWindowDestroy(window)
+      }
       if (nonNullDialog.isShowing) {
         val dialogContext =
             ContextUtils.findContextOfType(nonNullDialog.context, Activity::class.java)
@@ -341,6 +344,7 @@ public class ReactModalHostView(context: ThemedReactContext) :
       newDialog.show()
       updateSystemAppearance()
       window.clearFlags(WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE)
+      (context as ThemedReactContext).onExtraWindowCreate(window)
     }
   }
 

packages/react-native/ReactAndroid/src/test/java/com/facebook/react/interfaces/ExtraWindowEventListenerTest.kt

@@ -0,0 +1,124 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+package com.facebook.react.interfaces
+
+import android.view.Window
+import com.facebook.react.bridge.ReactApplicationContext
+import com.facebook.react.bridge.ReactTestHelper
+import com.facebook.testutils.shadows.ShadowSoLoader
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.kotlin.mock
+import org.mockito.kotlin.never
+import org.mockito.kotlin.times
+import org.mockito.kotlin.verify
+import org.robolectric.RobolectricTestRunner
+import org.robolectric.annotation.Config
+
+@RunWith(RobolectricTestRunner::class)
+@Config(shadows = [ShadowSoLoader::class])
+class ExtraWindowEventListenerTest {
+  private lateinit var reactContext: ReactApplicationContext
+  private lateinit var window: Window
+
+  @Before
+  fun setUp() {
+    reactContext = ReactTestHelper.createCatalystContextForTest()
+    window = mock()
+  }
+
+  @Test
+  fun testOnExtraWindowCreateNotifiesListener() {
+    val listener: ExtraWindowEventListener = mock()
+
+    reactContext.addExtraWindowEventListener(listener)
+    reactContext.onExtraWindowCreate(window)
+
+    verify(listener, times(1)).onExtraWindowCreate(window)
+  }
+
+  @Test
+  fun testOnExtraWindowDestroyNotifiesListener() {
+    val listener: ExtraWindowEventListener = mock()
+
+    reactContext.addExtraWindowEventListener(listener)
+    reactContext.onExtraWindowDestroy(window)
+
+    verify(listener, times(1)).onExtraWindowDestroy(window)
+  }
+
+  @Test
+  fun testMultipleListenersAreNotified() {
+    val listener1: ExtraWindowEventListener = mock()
+    val listener2: ExtraWindowEventListener = mock()
+
+    reactContext.addExtraWindowEventListener(listener1)
+    reactContext.addExtraWindowEventListener(listener2)
+    reactContext.onExtraWindowCreate(window)
+
+    verify(listener1, times(1)).onExtraWindowCreate(window)
+    verify(listener2, times(1)).onExtraWindowCreate(window)
+  }
+
+  @Test
+  fun testRemovedListenerIsNotNotified() {
+    val listener: ExtraWindowEventListener = mock()
+
+    reactContext.addExtraWindowEventListener(listener)
+    reactContext.removeExtraWindowEventListener(listener)
+    reactContext.onExtraWindowCreate(window)
+
+    verify(listener, never()).onExtraWindowCreate(window)
+  }
+
+  @Test
+  fun testOnlyRemovedListenerStopsReceivingEvents() {
+    val listener1: ExtraWindowEventListener = mock()
+    val listener2: ExtraWindowEventListener = mock()
+
+    reactContext.addExtraWindowEventListener(listener1)
+    reactContext.addExtraWindowEventListener(listener2)
+    reactContext.removeExtraWindowEventListener(listener1)
+    reactContext.onExtraWindowDestroy(window)
+
+    verify(listener1, never()).onExtraWindowDestroy(window)
+    verify(listener2, times(1)).onExtraWindowDestroy(window)
+  }
+
+  @Test
+  fun testListenerReceivesBothCreateAndDestroyEvents() {
+    val listener: ExtraWindowEventListener = mock()
+
+    reactContext.addExtraWindowEventListener(listener)
+    reactContext.onExtraWindowCreate(window)
+    reactContext.onExtraWindowDestroy(window)
+
+    verify(listener, times(1)).onExtraWindowCreate(window)
+    verify(listener, times(1)).onExtraWindowDestroy(window)
+  }
+
+  @Test
+  fun testNoListenersDoesNotCrash() {
+    // Should not throw when no listeners are registered
+    reactContext.onExtraWindowCreate(window)
+    reactContext.onExtraWindowDestroy(window)
+  }
+
+  @Test
+  fun testDuplicateAddIsIdempotent() {
+    val listener: ExtraWindowEventListener = mock()
+
+    reactContext.addExtraWindowEventListener(listener)
+    reactContext.addExtraWindowEventListener(listener)
+    reactContext.onExtraWindowCreate(window)
+
+    // CopyOnWriteArraySet deduplicates, so listener should only be called once
+    verify(listener, times(1)).onExtraWindowCreate(window)
+  }
+}

packages/react-native/ReactAndroid/src/test/java/com/facebook/react/uimanager/ThemedReactContextTest.kt

@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+package com.facebook.react.uimanager
+
+import android.view.Window
+import com.facebook.react.bridge.ReactApplicationContext
+import com.facebook.react.bridge.ReactTestHelper
+import com.facebook.react.interfaces.ExtraWindowEventListener
+import com.facebook.testutils.shadows.ShadowSoLoader
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.kotlin.mock
+import org.mockito.kotlin.times
+import org.mockito.kotlin.verify
+import org.robolectric.RobolectricTestRunner
+import org.robolectric.RuntimeEnvironment
+import org.robolectric.annotation.Config
+
+@RunWith(RobolectricTestRunner::class)
+@Config(shadows = [ShadowSoLoader::class])
+class ThemedReactContextTest {
+  private lateinit var reactApplicationContext: ReactApplicationContext
+  private lateinit var themedReactContext: ThemedReactContext
+  private lateinit var window: Window
+
+  @Before
+  fun setUp() {
+    reactApplicationContext = ReactTestHelper.createCatalystContextForTest()
+    themedReactContext =
+        ThemedReactContext(reactApplicationContext, RuntimeEnvironment.getApplication(), null, -1)
+    window = mock()
+  }
+
+  @Test
+  fun testAddExtraWindowEventListenerDelegatesToReactApplicationContext() {
+    val listener: ExtraWindowEventListener = mock()
+
+    themedReactContext.addExtraWindowEventListener(listener)
+    // Verify the listener was registered on the underlying context by dispatching an event
+    reactApplicationContext.onExtraWindowCreate(window)
+
+    verify(listener, times(1)).onExtraWindowCreate(window)
+  }
+
+  @Test
+  fun testRemoveExtraWindowEventListenerDelegatesToReactApplicationContext() {
+    val listener: ExtraWindowEventListener = mock()
+
+    themedReactContext.addExtraWindowEventListener(listener)
+    themedReactContext.removeExtraWindowEventListener(listener)
+    // After removal via ThemedReactContext, the listener should not be notified
+    reactApplicationContext.onExtraWindowCreate(window)
+
+    verify(listener, times(0)).onExtraWindowCreate(window)
+  }
+
+  @Test
+  fun testOnExtraWindowCreateDelegatesToReactApplicationContext() {
+    val listener: ExtraWindowEventListener = mock()
+
+    reactApplicationContext.addExtraWindowEventListener(listener)
+    // Dispatching via ThemedReactContext should reach listeners on the underlying context
+    themedReactContext.onExtraWindowCreate(window)
+
+    verify(listener, times(1)).onExtraWindowCreate(window)
+  }
+
+  @Test
+  fun testOnExtraWindowDestroyDelegatesToReactApplicationContext() {
+    val listener: ExtraWindowEventListener = mock()
+
+    reactApplicationContext.addExtraWindowEventListener(listener)
+    // Dispatching via ThemedReactContext should reach listeners on the underlying context
+    themedReactContext.onExtraWindowDestroy(window)
+
+    verify(listener, times(1)).onExtraWindowDestroy(window)
+  }
+}