下拉菜单

一个用于显示下拉菜单的 Jetpack Compose 下拉菜单组件。

Android

Included in Expo Go

GitHub

npm

更新日志

Recommended version:

~57.0.0

Expo UI DropdownMenu 与官方 Jetpack Compose Menu API 保持一致，并且会在按下触发元素时显示下拉菜单。

安装

Terminal

- npx expo install @expo/ui

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

用法

基本下拉菜单

BasicDropdownMenuExample.tsx

import {
  Host,
  DropdownMenu,
  DropdownMenuItem,
  OutlinedButton,
  Text,
  Icon,
} from '@expo/ui/jetpack-compose';
import { useState } from 'react';

const homeIcon = require('./assets/home.xml');

export default function BasicDropdownMenuExample() {
  const [isExpanded, setIsExpanded] = useState(false);
  return (
    <Host matchContents>
      <DropdownMenu expanded={isExpanded} onDismissRequest={() => setIsExpanded(false)}>
        <DropdownMenu.Trigger>
          <OutlinedButton onClick={() => setIsExpanded(true)}>Show menu</OutlinedButton>
        </DropdownMenu.Trigger>
        <DropdownMenu.Items>
          <DropdownMenuItem
            onClick={() => {
              setIsExpanded(false);
              console.log('Home pressed');
            }}>
            <DropdownMenuItem.Text>
              <Text>主页</Text>
            </DropdownMenuItem.Text>
            <DropdownMenuItem.LeadingIcon>
              <Icon source={homeIcon} size={24} />
            </DropdownMenuItem.LeadingIcon>
          </DropdownMenuItem>
        </DropdownMenu.Items>
      </DropdownMenu>
    </Host>
  );
}

将 React Native 组件作为触发器

你可以通过将 React Native 视图（例如 Pressable）包裹在 RNHostView 中，将其用作下拉菜单的触发器。

RNTriggerDropdownMenuExample.tsx

import {
  Host,
  DropdownMenu,
  DropdownMenuItem,
  Text as ComposeText,
  RNHostView,
} from '@expo/ui/jetpack-compose';
import { useState } from 'react';
import { Pressable, Text } from 'react-native';

export default function RNTriggerDropdownMenuExample() {
  const [isExpanded, setIsExpanded] = useState(false);
  return (
    <Host matchContents>
      <DropdownMenu expanded={isExpanded} onDismissRequest={() => setIsExpanded(false)}>
        <DropdownMenu.Trigger>
          <RNHostView matchContents>
            <Pressable
              onPress={() => setIsExpanded(true)}
              style={{
                alignSelf: 'flex-start',
                paddingHorizontal: 16,
                paddingVertical: 10,
                borderRadius: 8,
                backgroundColor: '#9B59B6',
              }}>
              <Text style={{ color: 'white', fontWeight: '600' }}>RN Pressable 触发器</Text>
            </Pressable>
          </RNHostView>
        </DropdownMenu.Trigger>
        <DropdownMenu.Items>
          <DropdownMenuItem onClick={() => setIsExpanded(false)}>
            <DropdownMenuItem.Text>
              <ComposeText>项目 1</ComposeText>
            </DropdownMenuItem.Text>
          </DropdownMenuItem>
          <DropdownMenuItem onClick={() => setIsExpanded(false)}>
            <DropdownMenuItem.Text>
              <ComposeText>项目 2</ComposeText>
            </DropdownMenuItem.Text>
          </DropdownMenuItem>
        </DropdownMenu.Items>
      </DropdownMenu>
    </Host>
  );
}

长按触发器

Jetpack Compose 没有专门的长按菜单原语——你可以通过在触发视图上使用 combinedClickable 修饰符，并配合现有的受控 DropdownMenu 来组合实现。菜单会自动锚定到触发器。

LongPressDropdownMenuExample.tsx

import { Host, DropdownMenu, DropdownMenuItem, Text } from '@expo/ui/jetpack-compose';
import { background, combinedClickable } from '@expo/ui/jetpack-compose/modifiers';
import { useState } from 'react';

export default function LongPressDropdownMenuExample() {
  const [isExpanded, setIsExpanded] = useState(false);
  return (
    <Host matchContents>
      <DropdownMenu expanded={isExpanded} onDismissRequest={() => setIsExpanded(false)}>
        <DropdownMenu.Trigger>
          <Text
            modifiers={[
              background('#e0e0e0'),
              combinedClickable({
                onClick: () => console.log('短按'),
                onLongClick: () => setIsExpanded(true),
              }),
            ]}>
            长按我
          </Text>
        </DropdownMenu.Trigger>
        <DropdownMenu.Items>
          <DropdownMenuItem onClick={() => setIsExpanded(false)}>
            <DropdownMenuItem.Text>
              <Text>复制</Text>
            </DropdownMenuItem.Text>
          </DropdownMenuItem>
          <DropdownMenuItem
            elementColors={{ textColor: '#B3261E' }}
            onClick={() => setIsExpanded(false)}>
            <DropdownMenuItem.Text>
              <Text>删除</Text>
            </DropdownMenuItem.Text>
          </DropdownMenuItem>
        </DropdownMenu.Items>
      </DropdownMenu>
    </Host>
  );
}

API

import { DropdownMenu } from '@expo/ui/jetpack-compose';

Components

`DropdownMenu`

Android

Type: React.Element<DropdownMenuProps>

Props of the DropdownMenu component.

DropdownMenuProps

`children`

Android

Type: ReactNode

The contents of the submenu are used as an anchor for the dropdown menu. The children will be wrapped in a pressable element, which triggers opening of the dropdown menu.

`color`

Android

Optional • Type: ColorValue

The color of the container holding the dropdown menu items.

`expanded`

Android

Optional • Type: boolean

Whether the dropdown menu is expanded (visible).

`modifiers`

Android

Optional • Type: ModifierConfig[]

Modifiers for the component.

`onDismissRequest`

Android

Optional • Type: () => void

Callback fired when the menu requests to be dismissed (e.g. tapping outside). Must be provided when expanded is true to allow the menu to close.

`style`

Android

Optional • Type: StyleProp<ViewStyle>

Optional styles to apply to the DropdownMenu.

`DropdownMenuItem`

Android

Type: React.Element<DropdownMenuItemProps>

A dropdown menu item component that wraps Compose's DropdownMenuItem. Should be used inside DropdownMenu.Items or ExposedDropdownMenu.

`Items`

Android

Type: React.Element<{ children: ReactNode }>

Container for items displayed in the dropdown menu. Children should be DropdownMenuItem components or other native views.

`Preview`

Android

Type: React.Element<{ children: ReactNode }>

Preview content shown during long press (iOS only).

`Trigger`

Android

Type: React.Element<{ children: ReactNode }>

Container for the trigger element that opens the dropdown menu.