리엑트 네이티브 SwitchNavigator 사용 하기

import { createStackNavigator } from 'react-navigation-stack';
import { createAppContainer, createSwitchNavigator } from 'react-navigation';
import { createDrawerNavigator } from 'react-navigation-drawer';

import login from './Login/login'
import intro from './intro'


// 로그인과 인트로 화면은, 스텍으로 
const Loging_in_Index = createStackNavigator(
    {
        login: { screen: login }
    }
)

const Intro_in_Index = createStackNavigator(
    {
        intro :{screen:intro }
    }
)



const Start_View = createAppContainer(

    createSwitchNavigator(
        {
            Loging_in_Index:Loging_in_Index,
            Intro_in_Index:Intro_in_Index
        },
        {
            initialRouteName: 'Intro_in_Index',
        }

    )
    
)

export default Start_View