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Expo NavigationBar
一个库,提供对 Android 上原生导航栏的各种交互的访问。
expo-navigation-bar 提供了一个组件和命令式 API,用于控制 Android 设备上的应用导航栏,允许你更改其按钮的颜色或隐藏它。
安装
🌐 Installation
- npx expo install expo-navigation-barIf you are installing this in an existing React Native app, make sure to install expo in your project.
应用配置中的配置
🌐 Configuration in app config
如果你在项目中使用配置插件(连续原生生成 (CNG)),可以使用其内置的 配置插件 来配置 expo-navigation-bar。该插件允许你配置无法在运行时设置并且需要构建新的应用二进制文件才能生效的各种属性。如果你的应用不使用 CNG,那么你需要手动配置该库。
🌐 You can configure expo-navigation-bar using its built-in config plugin if you use config plugins in your project (Continuous Native Generation (CNG)). The plugin allows you to configure various properties that cannot be set at runtime and require building a new app binary to take effect. If your app does not use CNG, then you'll need to manually configure the library.
Example app.json with config plugin
{ "expo": { "plugins": [ [ "expo-navigation-bar", { "enforceContrast": true, "hidden": false, "style": "light" } ] ] } }
Configurable properties
| Name | Default | Description |
|---|---|---|
enforceContrast | true | Only for: Android Determines whether the operating system should keep the navigation bar translucent to provide contrast between the navigation buttons and app content. Has no effect on Android 9 and below. |
hidden | undefined | Only for: Android Determines whether the status bar starts hidden. Accepts |
style | undefined | Only for: Android Determines which style the navigation bar starts with. Accepts |
Are you using this library in an existing React Native app?
如果你没有使用连续本地生成(CNG)或者你正在手动使用一个原生 Android 项目,那么你需要将以下配置添加到你的原生项目中:
🌐 If you're not using Continuous Native Generation (CNG) or you're using a native android project manually, then you need to add the following configuration to your native project:
-
要在 Android 上隐藏导航栏,请在 android/app/src/main/res/values/styles.xml 中添加
expoNavigationBarHidden:<style name="AppTheme" parent="Theme.AppCompat.DayNight.NoActionBar"> <!-- ... --> <item name="expoNavigationBarHidden">true</item> </style>
用法
🌐 Usage
import { StyleSheet, Text, View } from 'react-native'; import { NavigationBar } from 'expo-navigation-bar'; export default function App() { return ( <View style={styles.container}> <Text style={styles.text}>Notice that the navigation bar has light buttons!</Text> <NavigationBar style="light" /> </View> ); } const styles = StyleSheet.create({ container: { flex: 1, backgroundColor: '#000', alignItems: 'center', justifyContent: 'center', }, text: { color: '#fff', }, });
应用接口
🌐 API
import { NavigationBar } from 'expo-navigation-bar';
Component
Type: React.Element<NavigationBarProps>
A component that allows you to configure your navigation bar declaratively.
You will likely have multiple NavigationBar components mounted in the same app at the same time.
For example, if you have multiple screens in your app, you may end up using one per screen.
The props of each NavigationBar component will be merged in the order that they were mounted.
NavigationBarStyle • Default: 'auto'Sets the color of the navigation bar buttons. Default value is "auto"
which picks the appropriate value according to the active color scheme,
eg: if your app is dark mode, the style will be "light".
This will have an effect when the following conditions are met:
- The device navigation bar is using buttons.
- The
enforceContrastoption of theexpo-navigation-barplugin is set tofalse.
Due to a bug in the Android 15 emulator this function may have no effect. Try a physical device or an emulator with a different version of Android.
Component Methods
| Parameter | Type | Description |
|---|---|---|
| hidden | boolean | If the navigation bar should be hidden. |
Set the navigation bar's visibility.
voidExample
NavigationBar.setHidden(true);
| Parameter | Type | Description |
|---|---|---|
| style | NavigationBarStyle | The color of the navigation bar buttons. |
Sets the style of the navigation bar.
This will have an effect when the following conditions are met:
- The device navigation bar is using buttons.
- The
enforceContrastoption of theexpo-navigation-barplugin is set tofalse.
Due to a bug in the Android 15 emulator this function may have no effect. Try a physical device or an emulator with a different version of Android.
voidExample
NavigationBar.setStyle("dark");
Hooks
Deprecated: This will be removed in a future release.
React hook that statefully updates with the visibility of the system navigation bar.
NavigationBarVisibility | nullVisibility of the navigation bar, null during async initialization.
Methods
Deprecated: This will be removed in a future release.
Get the navigation bar's visibility.
Promise<NavigationBarVisibility>Navigation bar's current visibility status. Returns hidden on unsupported platforms (iOS, web).
Deprecated: Use
NavigationBar.setStyleinstead. This will be removed in a future release.
| Parameter | Type | Description |
|---|---|---|
| style | NavigationBarStyle | The color of the navigation bar buttons. |
voidDeprecated: Use
NavigationBar.setHiddeninstead. This will be removed in a future release.
| Parameter | Type | Description |
|---|---|---|
| visibility | NavigationBarVisibility | Based on CSS visibility property. |
Set the navigation bar's visibility.
Promise<void>Event Subscriptions
Deprecated: This will be removed in a future release.
| Parameter | Type |
|---|---|
| listener | (event: NavigationBarVisibilityEvent) => void |
Observe changes to the system navigation bar. Due to platform constraints, this callback will also be triggered when the status bar visibility changes.
EventSubscriptionTypes
Literal Type: string
Navigation bar style.
autowill automatically adjust based on the current theme.lighta light navigation bar with dark content.darka dark navigation bar with light content.invertedthe bar colors are inverted in relation to the current theme.
Acceptable values are: 'auto' | 'inverted' | 'light' | 'dark'
Deprecated: This will be removed in a future release.
Literal Type: string
Visibility of the navigation bar.
Acceptable values are: 'visible' | 'hidden'
Deprecated: This will be removed in a future release.
Current system UI visibility state. Due to platform constraints, this will return when the status bar visibility changes as well as the navigation bar.
| Property | Type | Description |
|---|---|---|
| rawVisibility | number | Native Android system UI visibility state, returned from the native Android |
| visibility | NavigationBarVisibility | Current navigation bar visibility. |