模态

了解如何在 Expo Router 中使用模态。

模态框是移动应用中的常见模式。它们是在当前屏幕之上渲染新屏幕的一种方式。它们通常用于创建新账户或用户从列表中选择选项等操作。

¥Modals are a common pattern in mobile apps. They are a way to present a new screen on top of the current screen. They are often used for things like creating a new account, or for a user to select an option from a list.

你可以通过创建将某些路由渲染为模态的根布局路由来实现模态。

¥You can implement a modal by creating a root layout route that renders certain routes as modals.

app

_layout.tsx

home.tsx

modal.tsx

布局路由 app/_layout.tsx 可以将组件渲染为模态框。添加一个名为 modal 的新路由，用于渲染模态：

¥The layout route app/_layout.tsx can present components as modals. Add a new route called modal that is used to render modals:

app/_layout.tsx

import { Stack } from 'expo-router';

export default function Layout() {
  return (
    <Stack>
      <Stack.Screen
        name="home"
        options={{
          // Hide the header for all other routes.
          headerShown: false,
        }}
      />
      <Stack.Screen
        name="modal"
        options={{
          // Set the presentation mode to modal for our modal route.
          presentation: 'modal',
        }}
      />
    </Stack>
  );
}

app/home.tsx

import { View, Text } from 'react-native';
import { Link } from 'expo-router';

export default function Home() {
  return (
    <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
      <Text>Home Screen</Text>
      <Link href="/modal">Present modal</Link>
    </View>
  );
}

现在创建一个模式，当模式丢失其先前的上下文并且必须作为独立页面渲染时，该模式会添加后退按钮。

¥Now create a modal that adds a back button when the modal has lost its previous context and must be presented as a standalone page.

app/modal.tsx

import { View, Platform } from 'react-native';
import { Link, router } from 'expo-router';
import { StatusBar } from 'expo-status-bar';

export default function Modal() {
  // If the page was reloaded or navigated to directly, then the modal should be presented as
  // a full screen page. You may need to change the UI to account for this.
  const isPresented = router.canGoBack();
  return (
    <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
      

{/* Use `../` as a simple way to navigate to the root. This is not analogous to "goBack". */}


      {!isPresented && <Link href="../">Dismiss</Link>}
      

{/* Native modals have dark backgrounds on iOS. Set the status bar to light content and add a fallback for other platforms with auto. */}


      <StatusBar style={Platform.OS === 'ios' ? 'light' : 'auto'} />
    </View>
  );
}