felixrieseberg/index.html

## index.html
<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8">
    <title>Hello World!</title>
  </head>
  <body>
    <h1>Hello World!</h1>
    <button onclick="window.postMessage('beep', '*')">Beep!</button>
  </body>
</html>

## main.js
// Modules to control application life and create native browser window
const {app, BrowserWindow, ipcMain} = require('electron')
const path = require('path')
const url = require('url')

// Keep a global reference of the window object, if you don't, the window will
// be closed automatically when the JavaScript object is garbage collected.
let mainWindow

function createWindow () {
  // Create the browser window.
  mainWindow = new BrowserWindow({
    width: 800,
    height: 600,
    webPreferences: {
      preload: path.join(__dirname, 'renderer.js'),
      contextIsolation: true,
      nodeIntegration: false
    }
  })

  ipcMain.on('hi', (...args) => console.log('hi', ...args))

  // and load the index.html of the app.
  mainWindow.loadFile('index.html')

  // Open the DevTools.
  // mainWindow.webContents.openDevTools()

  // Emitted when the window is closed.
  mainWindow.on('closed', function () {
    // Dereference the window object, usually you would store windows
    // in an array if your app supports multi windows, this is the time
    // when you should delete the corresponding element.
    mainWindow = null
  })
}

// This method will be called when Electron has finished
// initialization and is ready to create browser windows.
// Some APIs can only be used after this event occurs.
app.on('ready', createWindow)

// Quit when all windows are closed.
app.on('window-all-closed', function () {
  // On OS X it is common for applications and their menu bar
  // to stay active until the user quits explicitly with Cmd + Q
  if (process.platform !== 'darwin') {
    app.quit()
  }
})

app.on('activate', function () {
  // On OS X it's common to re-create a window in the app when the
  // dock icon is clicked and there are no other windows open.
  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.

## renderer.js
const {shell, webFrame, ipcRenderer} = require('electron')
const path = require('path')

// Set a variable in the page before it loads
webFrame.executeJavaScript('window.foo = "foo";')

// The loaded page will not be able to access this, it is only available
// in this context
window.bar = 'bar'

document.addEventListener('DOMContentLoaded', () => {
  // Will log out 'undefined' since window.foo is only available in the main
  // context
  console.log(window.foo)

  // Will log out 'bar' since window.bar is available in this context
  console.log(window.bar)

  document.body.addEventListener('click', (event) => {
    // Open clicked links externally
    if (event.target.tagName === 'A') {
      shell.openExternal(event.target.href)
      event.preventDefault()
    }
  })
})

window.addEventListener('message', (event) => {
  // Beep when the page requests it
  if (event.data === 'beep') {
    ipcRenderer.send('hi', 'beep')
    shell.beep()
  }
})
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="UTF-8">
	<title>Hello World!</title>
	</head>
	<body>
	<h1>Hello World!</h1>
	<button onclick="window.postMessage('beep', '*')">Beep!</button>
	</body>
	</html>
	// Modules to control application life and create native browser window
	const {app, BrowserWindow, ipcMain} = require('electron')
	const path = require('path')
	const url = require('url')

	// Keep a global reference of the window object, if you don't, the window will
	// be closed automatically when the JavaScript object is garbage collected.
	let mainWindow

	function createWindow () {
	// Create the browser window.
	mainWindow = new BrowserWindow({
	width: 800,
	height: 600,
	webPreferences: {
	preload: path.join(__dirname, 'renderer.js'),
	contextIsolation: true,
	nodeIntegration: false
	}
	})

	ipcMain.on('hi', (...args) => console.log('hi', ...args))

	// and load the index.html of the app.
	mainWindow.loadFile('index.html')

	// Open the DevTools.
	// mainWindow.webContents.openDevTools()

	// Emitted when the window is closed.
	mainWindow.on('closed', function () {
	// Dereference the window object, usually you would store windows
	// in an array if your app supports multi windows, this is the time
	// when you should delete the corresponding element.
	mainWindow = null
	})
	}

	// This method will be called when Electron has finished
	// initialization and is ready to create browser windows.
	// Some APIs can only be used after this event occurs.
	app.on('ready', createWindow)

	// Quit when all windows are closed.
	app.on('window-all-closed', function () {
	// On OS X it is common for applications and their menu bar
	// to stay active until the user quits explicitly with Cmd + Q
	if (process.platform !== 'darwin') {
	app.quit()
	}
	})

	app.on('activate', function () {
	// On OS X it's common to re-create a window in the app when the
	// dock icon is clicked and there are no other windows open.
	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.
	const {shell, webFrame, ipcRenderer} = require('electron')
	const path = require('path')

	// Set a variable in the page before it loads
	webFrame.executeJavaScript('window.foo = "foo";')

	// The loaded page will not be able to access this, it is only available
	// in this context
	window.bar = 'bar'

	document.addEventListener('DOMContentLoaded', () => {
	// Will log out 'undefined' since window.foo is only available in the main
	// context
	console.log(window.foo)

	// Will log out 'bar' since window.bar is available in this context
	console.log(window.bar)

	document.body.addEventListener('click', (event) => {
	// Open clicked links externally
	if (event.target.tagName === 'A') {
	shell.openExternal(event.target.href)
	event.preventDefault()
	}
	})
	})

	window.addEventListener('message', (event) => {
	// Beep when the page requests it
	if (event.data === 'beep') {
	ipcRenderer.send('hi', 'beep')
	shell.beep()
	}
	})