React-native-navigation hide navigation bar on login screen?

I have changed

 Navigation.startSingleScreenApp({
    screen: {
        label: "Login",
        screen: "LoginComponent",
        icon: require('./asset/menu.png'),
        title: "Login",
      }, 
      navigationBarStyle : {navBarHidden: true },
      passProps: {},
      animationType: 'slide-down'
  });

to

   Navigation.startSingleScreenApp({
        screen: {
         label: "Login",
        screen: "LoginComponent",
        icon: require('./asset/menu.png'),
        title: "Login",
       navigationBarStyle : {navBarHidden: true },
      }, 
      passProps: {},
      animationType: 'slide-down'
  });

And it works like as charm.