fix(iOS, Tabs): tab screen height when tabs are rendered dynamically

apps/src/tests/Test3425.tsx

@@ -0,0 +1,30 @@
+import React, { useState } from 'react';
+import { Button, View } from 'react-native';
+import Colors from '../shared/styling/Colors';
+import { TestBottomTabs } from '.';
+
+export default function App() {
+  const [index, setIndex] = useState(0);
+  return (
+    <View
+      style={{
+        flex: 1,
+        paddingHorizontal: 20,
+        paddingVertical: 100,
+        backgroundColor: Colors.BlueLight40,
+      }}>
+      {index === 0 ? (
+        <View
+          style={{
+            flex: 1,
+            justifyContent: 'center',
+            alignItems: 'center',
+          }}>
+          <Button title="Go to Bottom Tabs" onPress={() => setIndex(1)} />
+        </View>
+      ) : (
+        <TestBottomTabs />
+      )}
+    </View>
+  );
+}

apps/src/tests/index.ts

@@ -162,6 +162,7 @@ export { default as Test3342 } from './Test3342';
 export { default as Test3346 } from './Test3346';
 export { default as Test3369 } from './Test3369';
 export { default as Test3379 } from './Test3379';
+export { default as Test3425 } from './Test3425';
 export { default as TestScreenAnimation } from './TestScreenAnimation';
 export { default as TestScreenAnimationV5 } from './TestScreenAnimationV5';
 export { default as TestHeader } from './TestHeader';

ios/bottom-tabs/host/RNSBottomTabsHostComponentView.mm

@@ -146,6 +146,17 @@ - (void)reactAddControllerToClosestParent:(UIViewController *)controller
       if (parentView.reactViewController) {
         [parentView.reactViewController addChildViewController:controller];
         [self addSubview:controller.view];
+
+        // Enable auto-layout to ensure valid size of tabBarController.view.
+        // In host tree, tabBarController.view is the only child of HostComponentView.
+        controller.view.translatesAutoresizingMaskIntoConstraints = NO;
+        [NSLayoutConstraint activateConstraints:@[
+          [controller.view.topAnchor constraintEqualToAnchor:self.topAnchor],
+          [controller.view.bottomAnchor constraintEqualToAnchor:self.bottomAnchor],
+          [controller.view.leadingAnchor constraintEqualToAnchor:self.leadingAnchor],
+          [controller.view.trailingAnchor constraintEqualToAnchor:self.trailingAnchor]
+        ]];
+
         [controller didMoveToParentViewController:parentView.reactViewController];
         break;
       }