feat(ios): RCTViewControllerAppearanceListener

packages/react-native/Libraries/AppDelegate/RCTDefaultReactNativeFactoryDelegate.mm

@@ -7,6 +7,7 @@
 
 #import "RCTDefaultReactNativeFactoryDelegate.h"
 #import <ReactCommon/RCTHost.h>
+#import <React/RCTViewController.h>
 #import "RCTAppSetupUtils.h"
 #import "RCTDependencyProvider.h"
 #if USE_THIRD_PARTY_JSC != 1
@@ -28,7 +29,7 @@ - (NSURL *_Nullable)sourceURLForBridge:(nonnull RCTBridge *)bridge
 
 - (UIViewController *)createRootViewController
 {
-  return [UIViewController new];
+  return [RCTViewController new];
 }
 
 - (RCTBridge *)createBridgeWithDelegate:(id<RCTBridgeDelegate>)delegate launchOptions:(NSDictionary *)launchOptions

packages/react-native/React/Fabric/Mounting/ComponentViews/Modal/RCTFabricModalHostViewController.h

@@ -5,13 +5,13 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-#import <UIKit/UIKit.h>
+#import <React/RCTViewController.h>
 
 @protocol RCTFabricModalHostViewControllerDelegate <NSObject>
 - (void)boundsDidChange:(CGRect)newBounds;
 @end
 
-@interface RCTFabricModalHostViewController : UIViewController
+@interface RCTFabricModalHostViewController : RCTViewController
 
 @property (nonatomic, weak) id<RCTFabricModalHostViewControllerDelegate> delegate;
 

packages/react-native/React/Views/RCTModalHostViewController.h

@@ -5,12 +5,12 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-#import <UIKit/UIKit.h>
+#import <React/RCTViewController.h>
 
 #ifndef RCT_REMOVE_LEGACY_ARCH
 
 __attribute__((deprecated("This API will be removed along with the legacy architecture.")))
-@interface RCTModalHostViewController : UIViewController
+@interface RCTModalHostViewController : RCTViewController
 
 @property (nonatomic, copy) void (^boundsDidChangeBlock)(CGRect newBounds);
 

packages/react-native/React/Views/RCTViewController.h

@@ -0,0 +1,42 @@
+/*
+ * 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.
+ */
+
+#import <UIKit/UIKit.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@protocol RCTViewControllerAppearanceListener <NSObject>
+
+@optional
+- (void)reactViewControllerDidAppear:(UIViewController *)viewController animated:(BOOL)animated;
+- (void)reactViewControllerDidDisappear:(UIViewController *)viewController animated:(BOOL)animated;
+
+@end
+
+@interface UIViewController (RCTViewControllerAppearance)
+
+@property (nonatomic, assign, readonly) BOOL reactViewControllerIsVisible;
+
+- (void)reactAddViewControllerAppearanceListener:(id<RCTViewControllerAppearanceListener>)listener;
+- (void)reactRemoveViewControllerAppearanceListener:(id<RCTViewControllerAppearanceListener>)listener;
+
+/**
+ * Call from `viewDidAppear:` / `viewDidDisappear:` in UIViewController subclasses
+ * that cannot inherit from RCTViewController.
+ */
+- (void)reactNotifyViewControllerDidAppear:(BOOL)animated;
+- (void)reactNotifyViewControllerDidDisappear:(BOOL)animated;
+
+@end
+
+/**
+ * UIViewController subclass that forwards appearance events to registered listeners.
+ */
+@interface RCTViewController : UIViewController
+@end
+
+NS_ASSUME_NONNULL_END

packages/react-native/React/Views/RCTViewController.m

@@ -0,0 +1,90 @@
+/*
+ * 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.
+ */
+
+#import "RCTViewController.h"
+
+#import <objc/runtime.h>
+
+static void RCTSetViewControllerIsVisible(UIViewController *viewController, BOOL isVisible)
+{
+  objc_setAssociatedObject(
+      viewController, @selector(reactViewControllerIsVisible), @(isVisible), OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+}
+
+@implementation UIViewController (RCTViewControllerAppearance)
+
+- (NSHashTable<id<RCTViewControllerAppearanceListener>> *)reactViewControllerAppearanceListeners
+{
+  NSHashTable<id<RCTViewControllerAppearanceListener>> *listeners =
+      objc_getAssociatedObject(self, @selector(reactViewControllerAppearanceListeners));
+  if (!listeners) {
+    listeners = [NSHashTable weakObjectsHashTable];
+    objc_setAssociatedObject(
+        self, @selector(reactViewControllerAppearanceListeners), listeners, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+  }
+  return listeners;
+}
+
+- (BOOL)reactViewControllerIsVisible
+{
+  return [objc_getAssociatedObject(self, @selector(reactViewControllerIsVisible)) boolValue];
+}
+
+- (void)reactAddViewControllerAppearanceListener:(id<RCTViewControllerAppearanceListener>)listener
+{
+  [[self reactViewControllerAppearanceListeners] addObject:listener];
+
+  if (self.reactViewControllerIsVisible &&
+      [listener respondsToSelector:@selector(reactViewControllerDidAppear:animated:)]) {
+    [listener reactViewControllerDidAppear:self animated:NO];
+  }
+}
+
+- (void)reactRemoveViewControllerAppearanceListener:(id<RCTViewControllerAppearanceListener>)listener
+{
+  [[self reactViewControllerAppearanceListeners] removeObject:listener];
+}
+
+- (void)reactNotifyViewControllerDidAppear:(BOOL)animated
+{
+  RCTSetViewControllerIsVisible(self, YES);
+
+  for (id<RCTViewControllerAppearanceListener> listener in [self reactViewControllerAppearanceListeners].allObjects) {
+    if ([listener respondsToSelector:@selector(reactViewControllerDidAppear:animated:)]) {
+      [listener reactViewControllerDidAppear:self animated:animated];
+    }
+  }
+}
+
+- (void)reactNotifyViewControllerDidDisappear:(BOOL)animated
+{
+  RCTSetViewControllerIsVisible(self, NO);
+
+  for (id<RCTViewControllerAppearanceListener> listener in [self reactViewControllerAppearanceListeners].allObjects) {
+    if ([listener respondsToSelector:@selector(reactViewControllerDidDisappear:animated:)]) {
+      [listener reactViewControllerDidDisappear:self animated:animated];
+    }
+  }
+}
+
+@end
+
+@implementation RCTViewController
+
+- (void)viewDidAppear:(BOOL)animated
+{
+  [super viewDidAppear:animated];
+  [self reactNotifyViewControllerDidAppear:animated];
+}
+
+- (void)viewDidDisappear:(BOOL)animated
+{
+  [super viewDidDisappear:animated];
+  [self reactNotifyViewControllerDidDisappear:animated];
+}
+
+@end

packages/react-native/React/Views/RCTWrapperViewController.h

@@ -5,11 +5,11 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-#import <UIKit/UIKit.h>
+#import <React/RCTViewController.h>
 
 @class RCTWrapperViewController;
 
-@interface RCTWrapperViewController : UIViewController
+@interface RCTWrapperViewController : RCTViewController
 
 - (instancetype)initWithContentView:(UIView *)contentView NS_DESIGNATED_INITIALIZER;
 

packages/react-native/scripts/ios-prebuild/templates/React-umbrella.h

@@ -274,6 +274,7 @@
 #import <React/RCTVibration.h>
 #import <React/RCTVibrationPlugins.h>
 #import <React/RCTView.h>
+#import <React/RCTViewController.h>
 #import <React/RCTViewManager.h>
 #import <React/RCTViewUtils.h>
 #import <React/RCTVirtualTextShadowView.h>