app.js

const {
  app, BrowserWindow, TouchBar, nativeImage,
} = require('electron');

const { TouchBarButton } = TouchBar;

app.on('ready', () => {
  const win = new BrowserWindow({
    width: 800,
    height: 600,
    webPreferences: {
      nodeIntegration: true,
    },
  });

  let counter = 0;

  const image = nativeImage.createFromPath('./m.png').resize({ height: 30 });

  const update = () => {
    counter += 1;
    button.label = `Count: ${counter}`;
  };
  const button = new TouchBarButton({
    label: `Count: ${counter}`,
    accessibilityLabel: 'Counter',
    backgroundColor: '#6ab04c',
    click: () => {
      update();
    },
  });

  const button2 = new TouchBarButton({
    icon: image,
    iconPosition: 'left',
    label: 'How to use TouchBar API in ElectronJS?',
    accessibilityLabel: 'Button looking like a label',
    backgroundColor: '#000',
    click: () => {
      win.loadURL('https://medium.com/p/c58914a5518a');
    },
  });


  const touchBar = new TouchBar({
    items: [
      button,
      button2,
    ],
  });
  win.loadFile('index.html');
  win.setTouchBar(touchBar);
});