next.js/examples/with-electron/main/index.js

// Native
const { join } = require('path')
const { format } = require('url')

// Packages
const { BrowserWindow, app, ipcMain } = require('electron')
const isDev = require('electron-is-dev')
const prepareNext = require('electron-next')

// Prepare the renderer once the app is ready
app.on('ready', async () => {
  await prepareNext('./renderer')

  const mainWindow = new BrowserWindow({
    width: 800,
    height: 600,
    webPreferences: {
      nodeIntegration: false,
      preload: join(__dirname, 'preload.js')
    }
  })

  const url = isDev
    ? 'http://localhost:8000/start'
    : format({
      pathname: join(__dirname, '../renderer/start/index.html'),
      protocol: 'file:',
      slashes: true
    })

  mainWindow.loadURL(url)
})

// Quit the app once all windows are closed
app.on('window-all-closed', app.quit)

// listen the channel `message` and resend the received message to the renderer process
ipcMain.on('message', (event, message) => {
  event.sender.send('message', message)
})