宿主
一个 SwiftUI Host 组件,用于在 React Native 中启用 SwiftUI 组件。
For the complete documentation index, see llms.txt. Use this file to discover all available pages.
如需跨平台使用,请参阅通用的Host——它会根据平台渲染相应的原生组件。
一个组件,允许你在 React Native 中放置其他 @expo/ui/swift-ui 组件。它的作用类似于 DOM 中的 <svg>、react-native-skia 中的 <Canvas>,其内部使用 UIHostingController 在 UIKit 中渲染 SwiftUI 视图。
由于 Host 组件是一个 React Native View,你可以向它传入 style 属性,或者传入 matchContents 属性,使 Host 组件的尺寸与内容大小一致。
安装
- npx expo install @expo/uiIf you are installing this in an existing React Native app, make sure to install expo in your project.
使用
匹配内容尺寸
使用 matchContents 让 Host 自动调整自身大小以适配其 SwiftUI 内容,而不是要求显式指定尺寸。
import { Button, Host } from '@expo/ui/swift-ui'; export default function MatchContentsExample() { return ( <Host matchContents> <Button onPress={() => { console.log('已按下'); }}> 点击 </Button> </Host> ); }
注意: 不要在与滚动容器(
ScrollView、List、Form、LazyHStack、LazyVStack)相同的轴上使用matchContents。matchContents会映射为 SwiftUI 的.fixedSize,这会使滚动容器按其内容大小布局。它还会导致视口之外没有可滚动的内容,因此滚动会悄无声息地停止工作。请使用matchContents={{ vertical: true }}并配合style={{ width: '100%' }}(或在滚动轴上任意有限宽度)。
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}>项目 {i}</Text> ))} </HStack> </ScrollView> </Host> ); }
使用 style 显式设置尺寸
使用 style 为 Host 设置显式尺寸,例如使用 flex: 1 填充可用空间。
import { Button, Host, VStack, Text } from '@expo/ui/swift-ui'; export default function ExplicitSizingExample() { return ( <Host style={{ flex: 1 }}> <VStack spacing={8}> <Text>你好,世界!</Text> <Button onPress={() => { console.log('已按下'); }}> 点击 </Button> </VStack> </Host> ); }
忽略键盘安全区域
当 React Native 已经在处理键盘避让时(例如使用 react-native-keyboard-controller),请使用 ignoreSafeArea="keyboard",以防止 SwiftUI 宿主应用自己的键盘内边距。
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="输入文本" multiline /> </Host> </KeyboardStickyView> </View> </KeyboardProvider> ); }
忽略所有安全区域
当你希望 SwiftUI 内容延伸到状态栏后方时,使用 ignoreSafeArea="all",这对于全屏遮罩或背景很有用。
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>此内容会延伸到状态栏和 Home 指示条后方。</Text> </VStack> </Host> ); }
接口
import { Host } from '@expo/ui/swift-ui';
Component
Type: React.Element<HostProps>
A hosting component for SwiftUI views.
stringThe color scheme of the host view.
Acceptable values are: 'light' | 'dark'
stringControls which safe area regions the SwiftUI hosting view should ignore. Can only be set once on mount.
'all'- ignores all safe area insets.'keyboard'- ignores only the keyboard safe area.
Acceptable values are: 'all' | 'keyboard'
stringThe layout direction for the SwiftUI content. Defaults to the current locale direction from I18nManager.
Acceptable values are: 'leftToRight' | 'rightToLeft'
union • Default: falseWhen true, the host view will update its size in the React Native view tree to match the content's layout from SwiftUI. Can be only set once on mount.
Acceptable values are: boolean | {
horizontal: boolean,
vertical: boolean
}
(event: {
nativeEvent: {
height: number,
width: number
}
}) => voidCallback function that is triggered when the SwiftUI content completes its layout. Provides the current dimensions of the content, which may change as the content updates.
StyleProp<ViewStyle>boolean • Default: falseWhen true and no explicit size is provided, the host will use the viewport size as the proposed size for SwiftUI layout.
This is particularly useful for SwiftUI views that need to fill their available space, such as Form.