Fix native gesture reattach (#3672)

## Description

In `NativeDetector` native gesture failed to reattach when child
changed.

## Test plan

Add a logging message in attach/detach in
`android/.../react/RNGestureHandlerRegistry.kt` and
`apple/RNGestureHandlerRegistry.m`
`
```ts
import * as React from 'react';
import { StyleSheet, Text, View, ScrollView, Button } from 'react-native';
import {
  GestureHandlerRootView,
  NativeDetector,
  useGesture,
} from 'react-native-gesture-handler';

export default function App() {
  const items = Array.from({ length: 5 }, (_, index) => `Item ${index + 1}`);
  const [enabled, setEnabled] = React.useState(true);
  const gesture = useGesture('NativeViewGestureHandler', {
    onBegin: (e) => {
      console.log('onBegin');
    },
    onStart: (e) => {
      console.log('onStart');
    }
  });

  const SV1 = () => (
    <ScrollView style={styles.scrollView1}>
      {items.map((item, index) => (
        <View key={index} style={styles.item}>
          <Text style={styles.text}>{item}</Text>
        </View>
      ))}
    </ScrollView>
  );

  const SV2 = () => (
    <ScrollView style={styles.scrollView2}>
      {items.map((item, index) => (
        <View key={index} style={styles.item}>
          <Text style={styles.text}>{item}</Text>
        </View>
      ))}
    </ScrollView>
  );

  return (
    <GestureHandlerRootView
      style={{ flex: 1, backgroundColor: 'white', paddingTop: 100 }}>
      <Button
        title="Swap the child"
        onPress={() => {
          setEnabled(!enabled);
        }}
      />
      <NativeDetector gesture={gesture}>
        {enabled ? <SV1 /> : <SV2 />}
      </NativeDetector >
    </GestureHandlerRootView >
  );
}

const styles = StyleSheet.create({
  scrollView1: {
    backgroundColor: 'pink',
    marginHorizontal: 20,
  },
  scrollView2: {
    backgroundColor: 'lightblue',
    marginHorizontal: 20,
  },

  item: {
    flexDirection: 'row',
    justifyContent: 'center',
    alignItems: 'center',
    padding: 20,
    margin: 2,
    backgroundColor: 'white',
    borderRadius: 10,
  },
  text: {
    fontSize: 20,
    color: 'black',
  },
});
```

Author: akwasniewski

packages/react-native-gesture-handler/android/src/main/java/com/swmansion/gesturehandler/react/RNGestureHandlerDetectorView.kt

@@ -13,7 +13,7 @@ class RNGestureHandlerDetectorView(context: Context) : ReactViewGroup(context) {
   private val reactContext: ThemedReactContext
     get() = context as ThemedReactContext
   private var handlersToAttach: List<Int>? = null
-  private var nativeHandlersToAttach: MutableSet<Int> = mutableSetOf()
+  private var nativeHandlers: MutableSet<Int> = mutableSetOf()
   private var attachedHandlers: MutableSet<Int> = mutableSetOf()
   private var moduleId: Int = -1
 
@@ -48,7 +48,7 @@ class RNGestureHandlerDetectorView(context: Context) : ReactViewGroup(context) {
   override fun addView(child: View, index: Int, params: LayoutParams?) {
     super.addView(child, index, params)
 
-    tryAttachHandlerToChildView(child.id)
+    tryAttachNativeHandlersToChildView(child.id)
   }
 
   override fun removeViewAt(index: Int) {
@@ -75,51 +75,47 @@ class RNGestureHandlerDetectorView(context: Context) : ReactViewGroup(context) {
       val tag = entry.key
 
       if (entry.value == GestureHandlerMutation.Attach) {
-        // It might happen that `attachHandlers` will be called before children are added into view hierarchy. In that case we cannot
-        // attach `NativeViewGestureHandlers` here and we have to do it in `addView` method.
         if (shouldAttachGestureToChildView(tag)) {
-          nativeHandlersToAttach.add(tag)
+          // It might happen that `attachHandlers` will be called before children are added into view hierarchy. In that case we cannot
+          // attach `NativeViewGestureHandlers` here and we have to do it in `addView` method.
+          nativeHandlers.add(tag)
         } else {
           registry.attachHandlerToView(tag, this.id, GestureHandler.ACTION_TYPE_NATIVE_DETECTOR)
-
           attachedHandlers.add(tag)
         }
       } else if (entry.value == GestureHandlerMutation.Detach) {
         registry.detachHandler(tag)
+        nativeHandlers.remove(tag)
         attachedHandlers.remove(tag)
       }
     }
 
-    // This covers the case where `NativeViewGestureHandlers` are attached after child views were created.
     val child = getChildAt(0)
 
+    // This covers the case where `NativeViewGestureHandlers` are attached after child views were created.
     if (child != null) {
-      tryAttachHandlerToChildView(child.id)
+      tryAttachNativeHandlersToChildView(child.id)
     }
   }
 
-  private fun tryAttachHandlerToChildView(childId: Int) {
+  private fun tryAttachNativeHandlersToChildView(childId: Int) {
     val registry = RNGestureHandlerModule.registries[moduleId]
       ?: throw Exception("Tried to access a non-existent registry")
 
-    for (tag in nativeHandlersToAttach) {
+    for (tag in nativeHandlers) {
       registry.attachHandlerToView(tag, childId, GestureHandler.ACTION_TYPE_NATIVE_DETECTOR)
 
       attachedHandlers.add(tag)
     }
-
-    nativeHandlersToAttach.clear()
   }
 
   private fun detachNativeGestureHandlers() {
     val registry = RNGestureHandlerModule.registries[moduleId]
       ?: throw Exception("Tried to access a non-existent registry")
 
-    for (tag in attachedHandlers) {
-      if (shouldAttachGestureToChildView(tag)) {
-        registry.detachHandler(tag)
-        attachedHandlers.remove(tag)
-      }
+    for (tag in nativeHandlers) {
+      registry.detachHandler(tag)
+      attachedHandlers.remove(tag)
     }
   }
 

packages/react-native-gesture-handler/apple/Handlers/RNNativeViewHandler.mm

@@ -13,8 +13,8 @@
 #endif
 
 #import <React/RCTConvert.h>
-#import <React/UIView+React.h>
 #import <React/RCTScrollViewComponentView.h>
+#import <React/UIView+React.h>
 
 #pragma mark RNDummyGestureRecognizer
 

packages/react-native-gesture-handler/apple/RNGestureHandlerDetector.h

@@ -20,7 +20,7 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (void)dispatchTouchEvent:(RNGestureHandlerDetectorEventEmitter::OnGestureHandlerTouchEvent)event;
 
-- (void)tryAttachHandlerToChildView;
+- (void)tryAttachNativeHandlersToChildView;
 
 - (void)detachNativeGestureHandlers;
 

packages/react-native-gesture-handler/apple/RNGestureHandlerDetector.mm

@@ -13,7 +13,7 @@
 
 @interface RNGestureHandlerDetector () <RCTRNGestureHandlerDetectorViewProtocol>
 
-@property (nonatomic, nonnull) NSMutableSet *nativeHandlersToAttach;
+@property (nonatomic, nonnull) NSMutableSet *nativeHandlers;
 @property (nonatomic, nonnull) NSMutableSet *attachedHandlers;
 
 @end
@@ -41,7 +41,7 @@ - (instancetype)initWithFrame:(CGRect)frame
     static const auto defaultProps = std::make_shared<const RNGestureHandlerDetectorProps>();
     _props = defaultProps;
     _moduleId = -1;
-    _nativeHandlersToAttach = [NSMutableSet set];
+    _nativeHandlers = [NSMutableSet set];
     _attachedHandlers = [NSMutableSet set];
   }
 
@@ -94,11 +94,11 @@ - (BOOL)shouldAttachGestureToSubview:(NSNumber *)handlerTag
   return [[[handlerManager registry] handlerWithTag:handlerTag] wantsToAttachDirectlyToView];
 }
 
-- (void)addSubview:(RNGHUIView *)view
+- (void)didAddSubview:(RNGHUIView *)view
 {
-  [super addSubview:view];
+  [super didAddSubview:view];
 
-  [self tryAttachHandlerToChildView];
+  [self tryAttachNativeHandlersToChildView];
 }
 
 - (void)willRemoveSubview:(RNGHUIView *)subview
@@ -152,7 +152,9 @@ - (void)updateProps:(const Props::Shared &)propsBase oldProps:(const Props::Shar
 
     if (handlerChange.second == RNGestureHandlerMutationAttach) {
       if ([self shouldAttachGestureToSubview:handlerTag]) {
-        [_nativeHandlersToAttach addObject:handlerTag];
+        // It might happen that `attachHandlers` will be called before children are added into view hierarchy. In that
+        // case we cannot attach `NativeViewGestureHandlers` here and we have to do it in `didAddSubview` method.
+        [_nativeHandlers addObject:handlerTag];
       } else {
         [handlerManager.registry attachHandlerWithTag:handlerTag
                                                toView:self
@@ -163,40 +165,40 @@ - (void)updateProps:(const Props::Shared &)propsBase oldProps:(const Props::Shar
     } else if (handlerChange.second == RNGestureHandlerMutationDetach) {
       [handlerManager.registry detachHandlerWithTag:handlerTag];
       [_attachedHandlers removeObject:handlerTag];
+      [_nativeHandlers removeObject:handlerTag];
     }
+  }
 
-    [self tryAttachHandlerToChildView];
+  // This covers the case where `NativeViewGestureHandlers` are attached after child views were created.
+  if (!self.subviews[0]) {
+    [self tryAttachNativeHandlersToChildView];
   }
 
   [super updateProps:propsBase oldProps:oldPropsBase];
   // Override to force hittesting to work outside bounds
   self.clipsToBounds = NO;
 }
 
-- (void)tryAttachHandlerToChildView
+- (void)tryAttachNativeHandlersToChildView
 {
   RNGestureHandlerManager *handlerManager = [RNGestureHandlerModule handlerManagerForModuleId:_moduleId];
 
-  for (NSNumber *handlerTag in _nativeHandlersToAttach) {
+  for (NSNumber *handlerTag in _nativeHandlers) {
     [handlerManager.registry attachHandlerWithTag:handlerTag
                                            toView:self.subviews[0]
                                    withActionType:RNGestureHandlerActionTypeNativeDetector];
 
     [_attachedHandlers addObject:handlerTag];
   }
-
-  [_nativeHandlersToAttach removeAllObjects];
 }
 
 - (void)detachNativeGestureHandlers
 {
   RNGestureHandlerManager *handlerManager = [RNGestureHandlerModule handlerManagerForModuleId:_moduleId];
 
-  for (NSNumber *handlerTag in _attachedHandlers) {
-    if ([self shouldAttachGestureToSubview:handlerTag]) {
-      [[handlerManager registry] detachHandlerWithTag:handlerTag];
-      [_attachedHandlers removeObject:handlerTag];
-    }
+  for (NSNumber *handlerTag in _nativeHandlers) {
+    [[handlerManager registry] detachHandlerWithTag:handlerTag];
+    [_attachedHandlers removeObject:handlerTag];
   }
 }
 

packages/react-native-gesture-handler/apple/RNGestureHandlerModule.h

@@ -6,7 +6,8 @@
 
 #import "RNGestureHandlerManager.h"
 
-@interface RNGestureHandlerModule : RCTEventEmitter<NativeRNGestureHandlerModuleSpec, RCTJSDispatcherModule, RCTInitializing>
+@interface RNGestureHandlerModule
+    : RCTEventEmitter <NativeRNGestureHandlerModuleSpec, RCTJSDispatcherModule, RCTInitializing>
 
 + (RNGestureHandlerManager *)handlerManagerForModuleId:(int)moduleId;
 

packages/react-native-gesture-handler/apple/RNGestureHandlerModule.mm

@@ -71,7 +71,6 @@ - (void)invalidate
   });
 
   _managers[_moduleId] = nullptr;
-
 }
 
 - (dispatch_queue_t)methodQueue