main.js

const electron = require('electron')
// Module to control application life.
const app = electron.app
// Module to create native browser window.
const BrowserWindow = electron.BrowserWindow

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.
    /*
    @TODO add icon
     icon (NativeImage | String) (optional) - The window icon.
     On Windows it is recommended to use ICO icons to get best visual effects,
     you can also leave it undefined so the executable’s icon will be used.
     https://electron.atom.io/docs/api/native-image/
     */
    let winParams = {
        title: "Mindmaps Desktop",
        width: 800,
        height: 600,
        show: false,
        autoHideMenuBar: true
    };
    mainWindow = new BrowserWindow(winParams)

    mainWindow.once('ready-to-show', () => {
        mainWindow.show()
    })

    // and load the index.html of the app.
    mainWindow.loadURL(url.format({
        pathname: path.join(__dirname, path.join('app', 'index.html')),
        protocol: 'file:',
        slashes: true
    }))

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

    //fix windows closing
    mainWindow.on('close', function(){
        // TODO: add alert that unsaved changes may be lost
        mainWindow.destroy();
    })

    // 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.