Migrate RCTEventEmitter to Kotlin

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/animated/EventAnimationDriver.kt

@@ -25,17 +25,17 @@ internal class EventAnimationDriver(
     @JvmField internal var valueNode: ValueAnimatedNode
 ) : RCTModernEventEmitter {
   @Deprecated("Deprecated in Java")
-  override fun receiveEvent(targetReactTag: Int, eventName: String, event: WritableMap?) =
-      receiveEvent(-1, targetReactTag, eventName, event)
+  override fun receiveEvent(targetTag: Int, eventName: String, params: WritableMap?) =
+      receiveEvent(-1, targetTag, eventName, params)
 
   override fun receiveEvent(
       surfaceId: Int,
       targetTag: Int,
       eventName: String,
-      event: WritableMap?
+      params: WritableMap?
   ) =
       // We assume this event can't be coalesced. `customCoalesceKey` has no meaning in Fabric.
-      receiveEvent(surfaceId, targetTag, eventName, false, 0, event, EventCategoryDef.UNSPECIFIED)
+      receiveEvent(surfaceId, targetTag, eventName, false, 0, params, EventCategoryDef.UNSPECIFIED)
 
   @Deprecated("Deprecated in Java")
   override fun receiveTouches(
@@ -47,7 +47,7 @@ internal class EventAnimationDriver(
   }
 
   @Deprecated("Deprecated in Java")
-  override fun receiveTouches(touchEvent: TouchEvent) {
+  override fun receiveTouches(event: TouchEvent) {
     throw UnsupportedOperationException("receiveTouches is not support by native animated events")
   }
 
@@ -57,13 +57,13 @@ internal class EventAnimationDriver(
       eventName: String,
       canCoalesceEvent: Boolean,
       customCoalesceKey: Int,
-      event: WritableMap?,
+      params: WritableMap?,
       @EventCategoryDef category: Int
   ) {
-    requireNotNull(event) { "Native animated events must have event data." }
+    requireNotNull(params) { "Native animated events must have event data." }
 
     // Get the new value for the node by looking into the event map using the provided event path.
-    var currMap: ReadableMap? = event
+    var currMap: ReadableMap? = params
     var currArray: ReadableArray? = null
     for (i in 0 until eventPath.size - 1) {
       if (currMap != null) {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/fabric/events/FabricEventEmitter.kt

@@ -18,22 +18,22 @@ import com.facebook.systrace.Systrace
 
 public class FabricEventEmitter(private val uiManager: FabricUIManager) : RCTModernEventEmitter {
   @Deprecated("Deprecated in Java")
-  public override fun receiveEvent(reactTag: Int, eventName: String, params: WritableMap?): Unit {
-    receiveEvent(ViewUtil.NO_SURFACE_ID, reactTag, eventName, params)
+  public override fun receiveEvent(targetTag: Int, eventName: String, params: WritableMap?): Unit {
+    receiveEvent(ViewUtil.NO_SURFACE_ID, targetTag, eventName, params)
   }
 
   public override fun receiveEvent(
       surfaceId: Int,
-      reactTag: Int,
+      targetTag: Int,
       eventName: String,
       params: WritableMap?
   ) {
-    receiveEvent(surfaceId, reactTag, eventName, false, 0, params, EventCategoryDef.UNSPECIFIED)
+    receiveEvent(surfaceId, targetTag, eventName, false, 0, params, EventCategoryDef.UNSPECIFIED)
   }
 
   public override fun receiveEvent(
       surfaceId: Int,
-      reactTag: Int,
+      targetTag: Int,
       eventName: String,
       canCoalesceEvent: Boolean,
       customCoalesceKey: Int,
@@ -43,7 +43,7 @@ public class FabricEventEmitter(private val uiManager: FabricUIManager) : RCTMod
     Systrace.beginSection(
         Systrace.TRACE_TAG_REACT_JAVA_BRIDGE, "FabricEventEmitter.receiveEvent('$eventName')")
     try {
-      uiManager.receiveEvent(surfaceId, reactTag, eventName, canCoalesceEvent, params, category)
+      uiManager.receiveEvent(surfaceId, targetTag, eventName, canCoalesceEvent, params, category)
     } finally {
       Systrace.endSection(Systrace.TRACE_TAG_REACT_JAVA_BRIDGE)
     }

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/interop/InteropEventEmitter.kt

@@ -31,12 +31,12 @@ public class InteropEventEmitter(private val reactContext: ReactContext) : RCTEv
   private var eventDispatcherOverride: EventDispatcher? = null
 
   @Deprecated("Deprecated in Java")
-  override fun receiveEvent(targetReactTag: Int, eventName: String, eventData: WritableMap?) {
+  override fun receiveEvent(targetTag: Int, eventName: String, params: WritableMap?) {
     val dispatcher: EventDispatcher? =
         eventDispatcherOverride
-            ?: UIManagerHelper.getEventDispatcherForReactTag(reactContext, targetReactTag)
+            ?: UIManagerHelper.getEventDispatcherForReactTag(reactContext, targetTag)
     val surfaceId = UIManagerHelper.getSurfaceId(reactContext)
-    dispatcher?.dispatchEvent(InteropEvent(eventName, eventData, surfaceId, targetReactTag))
+    dispatcher?.dispatchEvent(InteropEvent(eventName, params, surfaceId, targetTag))
   }
 
   @Deprecated("Deprecated in Java")

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

@@ -0,0 +1,44 @@
+/*
+ * 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.events
+
+import com.facebook.proguard.annotations.DoNotStripAny
+import com.facebook.react.bridge.JavaScriptModule
+import com.facebook.react.bridge.WritableArray
+import com.facebook.react.bridge.WritableMap
+
+/**
+ * Paper JS interface to emit events from native to JS.
+ *
+ * Deprecated in favor of [RCTModernEventEmitter], which works with both the old and new renderer.
+ */
+@DoNotStripAny
+@Deprecated("Use [RCTModernEventEmitter] instead")
+public interface RCTEventEmitter : JavaScriptModule {
+  /**
+   * @param targetTag react tag of the view that receives the event
+   * @param eventName name of event
+   * @param params event params
+   */
+  @Deprecated("Use [RCTModernEventEmitter.receiveEvent] instead")
+  public fun receiveEvent(targetTag: Int, eventName: String, params: WritableMap?)
+
+  /**
+   * Receive and process touches
+   *
+   * @param eventName JS event name
+   * @param touches active pointers data
+   * @param changedIndices indices of changed pointers
+   */
+  @Deprecated("Dispatch the TouchEvent using [EventDispatcher] instead")
+  public fun receiveTouches(
+      eventName: String,
+      touches: WritableArray,
+      changedIndices: WritableArray
+  )
+}

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

@@ -0,0 +1,37 @@
+/*
+ * 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.events
+
+import com.facebook.react.bridge.WritableMap
+
+/**
+ * This is a transitional replacement for [RCTEventEmitter] that works with Fabric and non-Fabric
+ * renderers. [RCTEventEmitter] works with Fabric as well, but there are negative perf implications
+ * and it should be avoided.
+ *
+ * This interface will *also* be deleted in the distant future and be replaced with a new interface
+ * that doesn't need the old `receiveEvent` method at all. But for the foreseeable future, this is
+ * the recommended interface to use for EventEmitters.
+ */
+@Suppress("DEPRECATION")
+public interface RCTModernEventEmitter : RCTEventEmitter {
+  public fun receiveEvent(surfaceId: Int, targetTag: Int, eventName: String, params: WritableMap?)
+
+  public fun receiveEvent(
+      surfaceId: Int,
+      targetTag: Int,
+      eventName: String,
+      canCoalesceEvent: Boolean,
+      customCoalesceKey: Int,
+      params: WritableMap?,
+      @EventCategoryDef category: Int
+  )
+
+  @Deprecated("Dispatch the TouchEvent using [EventDispatcher] instead")
+  public fun receiveTouches(event: TouchEvent)
+}

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

@@ -45,18 +45,18 @@ internal class ReactEventEmitter(private val reactContext: ReactApplicationConte
   }
 
   @Deprecated("Please use RCTModernEventEmitter")
-  override fun receiveEvent(targetReactTag: Int, eventName: String, event: WritableMap?) {
-    receiveEvent(-1, targetReactTag, eventName, event)
+  override fun receiveEvent(targetTag: Int, eventName: String, params: WritableMap?) {
+    receiveEvent(-1, targetTag, eventName, params)
   }
 
   override fun receiveEvent(
       surfaceId: Int,
       targetTag: Int,
       eventName: String,
-      event: WritableMap?
+      params: WritableMap?
   ) {
     // We assume this event can't be coalesced. `customCoalesceKey` has no meaning in Fabric.
-    receiveEvent(surfaceId, targetTag, eventName, false, 0, event, EventCategoryDef.UNSPECIFIED)
+    receiveEvent(surfaceId, targetTag, eventName, false, 0, params, EventCategoryDef.UNSPECIFIED)
   }
 
   @Deprecated("Please use RCTModernEventEmitter")
@@ -108,25 +108,19 @@ internal class ReactEventEmitter(private val reactContext: ReactApplicationConte
 
   override fun receiveEvent(
       surfaceId: Int,
-      targetReactTag: Int,
+      targetTag: Int,
       eventName: String,
       canCoalesceEvent: Boolean,
       customCoalesceKey: Int,
-      event: WritableMap?,
+      params: WritableMap?,
       @EventCategoryDef category: Int
   ) {
-    @UIManagerType val uiManagerType = getUIManagerType(targetReactTag, surfaceId)
+    @UIManagerType val uiManagerType = getUIManagerType(targetTag, surfaceId)
     if (uiManagerType == UIManagerType.FABRIC) {
       fabricEventEmitter?.receiveEvent(
-          surfaceId,
-          targetReactTag,
-          eventName,
-          canCoalesceEvent,
-          customCoalesceKey,
-          event,
-          category)
+          surfaceId, targetTag, eventName, canCoalesceEvent, customCoalesceKey, params, category)
     } else if (uiManagerType == UIManagerType.DEFAULT) {
-      ensureDefaultEventEmitter()?.receiveEvent(targetReactTag, eventName, event)
+      ensureDefaultEventEmitter()?.receiveEvent(targetTag, eventName, params)
     }
   }