# Install & setup module
$ npm install react-native-override-user-interface-style --save
# --- or ---
$ yarn add react-native-override-user-interface-styl

# If you're developing your app using iOS, don't forget to run this command
$ cd ios/ && pod install

<key>AppGroup</key>
<string>your.group.name</string>

#import "AppDelegate.h"
#import <React/RCTBundleURLProvider.h>
#import <React/RCTRootView.h>
#import "RNUserInterfaceStyle.h" // <- add the header import

@implementation AppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    // ...other code

    [RNUserInterfaceStyle initSystemTheme];  // <- initialization system theme

    return YES;
}
@end

import com.humanscape.rarenote.RNUserInterfaceStyle.RNUserInterfaceStyleManager; // <- add this necessary import

public class MainActivity extends ReactActivity {
  @Override
    protected void onCreate(Bundle savedInstanceState) {
      RNUserInterfaceStyleManager.initSystemTheme(getApplicationContext(), "your preference name"); // <- initialization system theme
      super.onCreate(savedInstanceState);
    }
}

import RNUserInterfaceStyle from 'react-native-override-user-interface-style';

// or ES6+ destructured imports

import { getTheme, setTheme } from 'react-native-override-user-interface-style';

function getTheme():Promise<Theme | null>; // Gets saved theme type;
function setTheme(theme:Theme): void; // Set theme type