React Native can't find native method

I am new in React Native, here is my problem: I want to start an activity by calling NATIVE code from REACT NATIVE on a button click.

I am getting an error, says on the JS console 'cannot read property \'startActivity\'of undefined.

  ...MORE CODE...
  import ActivityStarter from './ActivityStarter'
  ...MORE CODE...

                <Button
            onPress={() => ActivityStarter.startActivity()}
            title='Login'  />

on the Java end:

public class ActivityStarterModule extends ReactContextBaseJavaModule {

public ActivityStarterModule(ReactApplicationContext reactContext) {
    super(reactContext);
}

@Override
public String getName() {
    return "ActivityStarter";
}

@ReactMethod
public void startActivity() {
    ReactApplicationContext context = getReactApplicationContext();
    Intent intent = new Intent(context, DashBoardScreen.class);
    context.startActivity(intent);
}}