Host

A SwiftUI Host component that enables SwiftUI components in React Native.

iOS

tvOS

Included in Expo Go

Recommended version:

~56.0.26

For cross-platform usage, see the universal Host — it renders the appropriate native component per platform.

A component that allows you to put the other @expo/ui/swift-ui components in React Native. It acts like <svg> for DOM, <Canvas> for react-native-skia, which internally uses UIHostingController to render the SwiftUI views in UIKit.

Since the Host component is a React Native View, you can pass the style prop to it or matchContents prop to make the Host component match the contents' size.

Installation

Terminal

- npx expo install @expo/ui

- yarn expo install @expo/ui

- pnpm expo install @expo/ui

- bun expo install @expo/ui

If you are installing this in an existing React Native app, make sure to install expo in your project.

Usage

Match contents sizing

Use matchContents to let the Host automatically size itself to fit its SwiftUI content, instead of requiring explicit dimensions.

Note: matchContents only works correctly with components that have an intrinsic size or an explicit frame (for example, Button, Toggle, Text). Flexible-width components like Slider and linear ProgressView expand to fill available space and have no intrinsic width, using matchContents with them will result in near-zero width. For those components, either apply a frame modifier on the component to give it an explicit width, or use explicit sizing with style on the Host instead (for example, style={{ flex: 1 }} or style={{ width: 300 }}).

MatchContentsExample.tsx

import { Button, Host } from '@expo/ui/swift-ui';

export default function MatchContentsExample() {
  return (
    <Host matchContents>
      <Button
        onPress={() => {
          console.log('Pressed');
        }}>
        Click
      </Button>
    </Host>
  );
}

Note: Do not use matchContents on the same axis as a scroll container (ScrollView, List, Form, LazyHStack, LazyVStack). matchContents resolves to SwiftUI's .fixedSize, which sizes the scroll container to its content. It also leaves nothing past the viewport to scroll into, so scrolling silently stops working. Use matchContents={{ vertical: true }} together with style={{ width: '100%' }} (or any finite width on the scroll axis).

ScrollViewMatchContents.tsx

import { Host, HStack, ScrollView, Text } from '@expo/ui/swift-ui';

export default function ScrollViewMatchContents() {
  return (
    <Host matchContents={{ vertical: true }} style={{ width: '100%' }}>
      <ScrollView axes="horizontal">
        <HStack spacing={12}>
          {Array.from({ length: 20 }).map((_, i) => (
            <Text key={i}>Item {i}</Text>
          ))}
        </HStack>
      </ScrollView>
    </Host>
  );
}

Explicit sizing with style

Use style to set explicit sizes on the Host, such as filling the available space with flex: 1.

ExplicitSizingExample.tsx

import { Button, Host, VStack, Text } from '@expo/ui/swift-ui';

export default function ExplicitSizingExample() {
  return (
    <Host style={{ flex: 1 }}>
      <VStack spacing={8}>
        <Text>Hello, world!</Text>
        <Button
          onPress={() => {
            console.log('Pressed');
          }}>
          Click
        </Button>
      </VStack>
    </Host>
  );
}

Ignoring keyboard safe area

Use ignoreSafeArea="keyboard" when React Native is already handling keyboard avoidance (for example, with react-native-keyboard-controller), to prevent the SwiftUI host from applying its own keyboard inset.

IgnoreKeyboardExample.tsx

import { Host, TextField } from '@expo/ui/swift-ui';
import { KeyboardProvider, KeyboardStickyView } from 'react-native-keyboard-controller';
import { View } from 'react-native';

export default function IgnoreKeyboardExample() {
  return (
    <KeyboardProvider>
      <View style={{ flex: 1, backgroundColor: 'black' }}>
        <KeyboardStickyView
          style={{
            position: 'absolute',
            bottom: 0,
            left: 0,
            right: 0,
            padding: 16,
            backgroundColor: 'green',
          }}>
          <Host matchContents ignoreSafeArea="keyboard" style={{ backgroundColor: 'red' }}>
            <TextField placeholder="Enter text" axis="vertical" />
          </Host>
        </KeyboardStickyView>
      </View>
    </KeyboardProvider>
  );
}

Ignoring the container safe area

Use ignoreSafeArea="container" to remove only the container safe area (notch, home indicator, status and navigation bars). The keyboard safe area still applies.

IgnoreContainerSafeAreaExample.tsx

import { Button, Host, HStack, Spacer } from '@expo/ui/swift-ui';
import { labelStyle } from '@expo/ui/swift-ui/modifiers';
import { useSafeAreaInsets } from 'react-native-safe-area-context';

export default function IgnoreContainerSafeAreaExample() {
  const insets = useSafeAreaInsets();
  return (
    <Host
      style={{ width: '100%', paddingTop: insets.top }}
      matchContents={{ vertical: true }}
      ignoreSafeArea="container">
      <HStack>
        <Button systemImage="chevron.backward" label="Back" modifiers={[labelStyle('iconOnly')]} />
        <Spacer />
        <Button
          systemImage="square.and.arrow.up"
          label="Share"
          modifiers={[labelStyle('iconOnly')]}
        />
      </HStack>
    </Host>
  );
}

Ignoring all safe areas

Use ignoreSafeArea="all" when you want SwiftUI content to extend behind the status bar and the keyboard, useful for full-screen overlays or backgrounds.

IgnoreAllSafeAreasExample.tsx

import { Host, Text, VStack } from '@expo/ui/swift-ui';

export default function IgnoreAllSafeAreasExample() {
  return (
    <Host
      ignoreSafeArea="all"
      style={{ position: 'absolute', top: 0, left: 0, right: 0, bottom: 0 }}>
      <VStack>
        <Text>This content extends behind the status bar and home indicator.</Text>
      </VStack>
    </Host>
  );
}

API

import { Host } from '@expo/ui/swift-ui';

No API data file found, sorry!