Blank page appear when keep App.js file data in Main.js file and imported in Login file

[VidyaCK]

I wanted to call this slid bar once after login. If I do so, I want to display any content. It shows only a blank page. But I can print all the statements which are in console.log where It went wrong I did not get it. Can you help me to solve this?

Main.js file contians App.js data

In App.js file ,

import React, { Component } from 'react';
import {
AppRegistry,
StyleSheet,
Text,
View,
Image,
NetInfo
} from 'react-native';
import Main from './src/components/Main';

export default class App extends Component {
render() {
return (
//call this inside if the condition

);
}
}

AppRegistry.registerComponent('App', () => App);

I must call this inside in if only.