Create StateWrapperImpl from C++ with its state (#59708)

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

Author: tomekzaw

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

@@ -28,8 +28,6 @@ import com.facebook.react.uimanager.StateWrapper
 @OptIn(UnstableReactNativeAPI::class)
 internal class StateWrapperImpl private constructor() : HybridClassBase(), ReferenceStateWrapper {
 
-  private external fun initHybrid()
-
   private external fun getStateDataImpl(): ReadableNativeMap?
 
   private external fun getStateMapBufferDataImpl(): ReadableMapBuffer?
@@ -65,10 +63,6 @@ internal class StateWrapperImpl private constructor() : HybridClassBase(), Refer
       return getStateDataReferenceImpl()
     }
 
-  init {
-    initHybrid()
-  }
-
   override fun updateState(map: WritableMap) {
     updateState(map, StateWrapper.UpdateMode.Asynchronous)
   }

packages/react-native/ReactAndroid/src/main/jni/react/fabric/FabricMountingManager.cpp

@@ -439,9 +439,8 @@ inline void writeCreateMountItem(
   // lifetime of the Java object
   jni::local_ref<StateWrapperImpl::JavaPart> javaStateWrapper = nullptr;
   if (mountItem.newChildShadowView.state != nullptr) {
-    javaStateWrapper = StateWrapperImpl::newObjectJavaArgs();
-    StateWrapperImpl* cStateWrapper = cthis(javaStateWrapper);
-    cStateWrapper->setState(mountItem.newChildShadowView.state);
+    javaStateWrapper =
+        StateWrapperImpl::newObjectCxxArgs(mountItem.newChildShadowView.state);
   }
 
   // Do not hold a reference to javaEventEmitter from the C++ side.
@@ -502,9 +501,7 @@ inline void writeUpdateStateMountItem(
   // lifetime of the Java object
   jni::local_ref<StateWrapperImpl::JavaPart> javaStateWrapper = nullptr;
   if (state != nullptr) {
-    javaStateWrapper = StateWrapperImpl::newObjectJavaArgs();
-    StateWrapperImpl* cStateWrapper = cthis(javaStateWrapper);
-    cStateWrapper->setState(state);
+    javaStateWrapper = StateWrapperImpl::newObjectCxxArgs(state);
   }
 
   buffer.writeObject(
@@ -1213,9 +1210,7 @@ void FabricMountingManager::preallocateRegisteredView(
   bool preventPassingStateWrapperForText =
       strcmp(shadowView.componentName, "Paragraph") == 0;
   if (shadowView.state != nullptr && !preventPassingStateWrapperForText) {
-    javaStateWrapper = StateWrapperImpl::newObjectJavaArgs();
-    StateWrapperImpl* cStateWrapper = cthis(javaStateWrapper);
-    cStateWrapper->setState(shadowView.state);
+    javaStateWrapper = StateWrapperImpl::newObjectCxxArgs(shadowView.state);
   }
 
   jni::local_ref<jobject> props = getProps({}, shadowView);

packages/react-native/ReactAndroid/src/main/jni/react/fabric/StateWrapperImpl.cpp

@@ -17,13 +17,6 @@ using namespace facebook::jni;
 
 namespace facebook::react {
 
-/**
- * Called from Java constructor through the JNI.
- */
-void StateWrapperImpl::initHybrid(jni::alias_ref<jhybridobject> jobj) {
-  return setCxxInstance(jobj);
-}
-
 jni::local_ref<ReadableNativeMap::jhybridobject>
 StateWrapperImpl::getStateDataImpl() {
   if (state_) {
@@ -71,7 +64,6 @@ std::shared_ptr<const State> StateWrapperImpl::getState() const {
 
 void StateWrapperImpl::registerNatives() {
   registerHybrid({
-      makeNativeMethod("initHybrid", StateWrapperImpl::initHybrid),
       makeNativeMethod("getStateDataImpl", StateWrapperImpl::getStateDataImpl),
       makeNativeMethod("updateStateImpl", StateWrapperImpl::updateStateImpl),
       makeNativeMethod(

packages/react-native/ReactAndroid/src/main/jni/react/fabric/StateWrapperImpl.h

@@ -32,9 +32,11 @@ class StateWrapperImpl : public jni::HybridClass<StateWrapperImpl, StateWrapper>
   std::shared_ptr<const State> getState() const;
 
  private:
-  std::shared_ptr<const State> state_;
+  friend HybridBase;
+
+  explicit StateWrapperImpl(std::shared_ptr<const State> state) : state_(std::move(state)) {}
 
-  static void initHybrid(jni::alias_ref<jhybridobject> jobj);
+  std::shared_ptr<const State> state_;
 };
 
 } // namespace facebook::react