main.js

const electron = require('electron')
const app = electron.app
const BrowserWindow = electron.BrowserWindow

const path = require('path')
const url = require('url')

let mainWindow

function createWindow () {
  mainWindow = new BrowserWindow({width: 450, height: 300, resizable: false})
  mainWindow.loadURL(url.format({
    pathname: path.join(__dirname, 'index.html'),
    protocol: 'file:',
    slashes: true
  }))
  // Open the DevTools.
  // mainWindow.webContents.openDevTools()
  mainWindow.on('closed', function () {mainWindow = null})
}

app.on('ready', createWindow)
app.on('window-all-closed', function () {
  if (process.platform !== 'darwin') {
    app.quit()
  }
})

app.on('activate', function () {if (mainWindow === null) {createWindow()}})

// In this file you can include the rest of your app's specific main process
// code. You can also put them in separate files and require them here.