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LazyVStack
一个用于懒加载垂直布局的 SwiftUI LazyVStack 组件。
iOS
tvOS
Included in Expo Go
Expo UI LazyVStack 与官方 SwiftUI LazyVStack API 保持一致,并将其子项垂直排列,仅在需要时(即在滚动过程中变为可见时)创建项目。
LazyVStack目前还不是真正的惰性加载:原生端只会构建可见项目,但 React 仍会预先创建所有子项,因此大型列表的挂载速度可能较慢。我们正在努力改进这一点。对于大型列表,我们建议使用 FlashList 或 Legend List。
安装
Terminal
- npx expo install @expo/uiIf you are installing this in an existing React Native app, make sure to install expo in your project.
用法
基础懒加载垂直堆栈
LazyVStack 应该在 ScrollView 内部使用,以启用懒加载渲染。
BasicLazyVStackExample.tsx
import { Host, ScrollView, LazyVStack, Text } from '@expo/ui/swift-ui'; export default function BasicLazyVStackExample() { return ( <Host style={{ flex: 1 }}> <ScrollView> <LazyVStack spacing={12}> {Array.from({ length: 100 }, (_, i) => ( <Text key={i}>{`Item ${i}`}</Text> ))} </LazyVStack> </ScrollView> </Host> ); }
带对齐
alignment 属性控制子元素的水平对齐方式。可用选项有:leading、center 和 trailing。
LazyVStackAlignmentExample.tsx
import { Host, ScrollView, LazyVStack, Rectangle } from '@expo/ui/swift-ui'; import { frame } from '@expo/ui/swift-ui/modifiers'; export default function LazyVStackAlignmentExample() { return ( <Host style={{ flex: 1 }}> <ScrollView> <LazyVStack spacing={12} alignment="leading"> <Rectangle modifiers={[frame({ width: 50, height: 50 })]} /> <Rectangle modifiers={[frame({ width: 100, height: 50 })]} /> <Rectangle modifiers={[frame({ width: 75, height: 50 })]} /> </LazyVStack> </ScrollView> </Host> ); }
API
import { LazyVStack } from '@expo/ui/swift-ui';
Component
Type: React.Element<LazyVStackProps>
Optional • Literal type:
stringThe horizontal alignment of children within the stack.
Acceptable values are: 'center' | 'leading' | 'trailing'
Type:
ReactNode