@khantsithu/expo-settings

It is a native module developed in accordance with the official Expo tutorial and tested with Expo Modules API 1.0: JSI & Fabric native modules with idiomatic Swift & Kotlin API..

Expo Tutorial: Creating a native module

Add the package to your npm dependencies

npm

npm install @khantsithu/expo-settings

or

Yarn

yarn add @khantsithu/expo-settings

Configure for Expo

Expo-Settings likely requires Expo SDK 46+.

expo install expo-build-properties

Add the expo-build-properties plugin to your app.json/app.config.js, setting the deployment target to 13.0 (or higher):

export default {
  plugins: [
    [
      "expo-build-properties",
      {
        ios: {
          deploymentTarget: "13.0",
        },
      },
    ],
  ],
};

Then, you'll need to rebuild your dev client. Expo-Settings will not work in Expo Go.

npx expo prebuild --clean
npx expo run:ios

Configure for Plain React Native

You must install expo-modules if they are not already installed.

npx install-expo-modules

and

cd ios
pod install

Usage and Example Code

import * as Settings from 'expo-settings';
import * as React from 'react';
import { Button, Text, View } from 'react-native';

export default function App() {
  const [theme, setTheme] = React.useState<string>(Settings.getTheme());

  React.useEffect(() => {
    const subscription = Settings.addThemeListener(({ theme: newTheme }) => {
      setTheme(newTheme);
    });
   
    return () => subscription.remove();
  }, [setTheme]);

  // Toggle between dark and light theme
  const nextTheme = theme === 'dark' ? 'light' : 'dark';

  return (
    <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
      <Text>Theme: {Settings.getTheme()}</Text>
      <Button title={`Set theme to ${nextTheme}`} onPress={() => Settings.setTheme(nextTheme)} />
    </View>
  );
}

Contribute

yarn build
cd example
npx expo run:ios # do this again whenever you change native code

You can edit the iOS files in ios/, and then update the JS accordingly in src.

Thanks

Special thanks to Fernando Rojo for the Twitter thread, as well as the Expo Team for developing the Expo Modules API.

Expo Modules made this so easy to build, and all with Swift and Kotlin