Color themes

Learn how to support light and dark modes in your app.

It's common for apps to support light and dark color schemes. Here is an example of how supporting both modes looks in an Expo project:

Configuration

Projects require additional configuration to support switching between light and dark modes for Android and iOS. However, no additional configuration is required for the web.

You can configure the supported appearance styles in app.json with the userInterfaceStyle property. You can also configure specific platforms to support different appearance styles by setting either android.userInterfaceStyle or ios.userInterfaceStyle to the preferred value.

The available options are:

• automatic: Follow system appearance settings and notify about any change the user makes
• light: Restrict the app to support light theme only
• dark: Restrict the app to support dark theme only

The app will default to the light style if this property is absent. Here is an example configuration:

{
  "expo": {
    "userInterfaceStyle": "automatic"
  }
}

In development builds, you'll need to install the native package expo-system-ui. Otherwise, the userInterfaceStyle property is ignored. You can also use the following command to check if the project is misconfigured:

If the project is misconfigured, you'll see a warning as shown below:

<activity android:configChanges="keyboard|keyboardHidden|orientation|screenSize|uiMode">

import android.content.Intent; // <--- import
import android.content.res.Configuration; // <--- import
public class MainActivity extends ReactActivity {
  // ...

  @Override
  public void onConfigurationChanged(Configuration newConfig) {
    super.onConfigurationChanged(newConfig);
    Intent intent = new Intent("onConfigurationChanged");
    intent.putExtra("newConfig", newConfig);
    sendBroadcast(intent);
  }
  // ...
}

Detect the color scheme

To detect the color scheme in your project, use Appearance or useColorScheme from react-native:

import { Appearance, useColorScheme } from 'react-native';

Then, you can use useColorScheme() hook as shown below:

function MyComponent() {
  let colorScheme = useColorScheme();

  if (colorScheme === 'dark') {
    // render some dark thing
  } else {
    // render some light thing
  }
}

In some cases, you will find it helpful to get the current color scheme imperatively with Appearance.getColorScheme() or listen to changes with Appearance.addChangeListener.

Minimal example

Don't forget to configure your project to support the automatic color scheme as described above in Configuration.

import { Text, StyleSheet, View, useColorScheme } from 'react-native';
import { StatusBar } from 'expo-status-bar'; // Automatically switches bar style based on theme.

export default function App() {
  const colorScheme = useColorScheme();

  const themeTextStyle = colorScheme === 'light' ? styles.lightThemeText : styles.darkThemeText;
  const themeContainerStyle =
    colorScheme === 'light' ? styles.lightContainer : styles.darkContainer;

  return (
    <View style={[styles.container, themeContainerStyle]}>
      <Text style={[styles.text, themeTextStyle]}>Color scheme: {colorScheme}</Text>
      <StatusBar />
    </View>
  );
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    alignItems: 'center',
    justifyContent: 'center',
  },
  text: {
    fontSize: 20,
  },
  lightContainer: {
    backgroundColor: '#d0d0c0',
  },
  darkContainer: {
    backgroundColor: '#242c40',
  },
  lightThemeText: {
    color: '#242c40',
  },
  darkThemeText: {
    color: '#d0d0c0',
  },
});

Tips

While you're developing your project, you can change your simulator's or device's appearance by using the following shortcuts:

• If using an Android Emulator, you can run adb shell "cmd uimode night yes" to enable dark mode, and adb shell "cmd uimode night no" to disable dark mode.
• If using a real device or an Android Emulator, you can toggle the system dark mode setting in the device's settings.
• If working with an iOS emulator locally, you can use the Cmd ⌘ + Shift + a shortcut to toggle between light and dark modes.