Electron tray: Drag and Drop events demo

main.js

var app = require('app');
var Menu = require('menu');
var Tray = require('tray');

var appIcon = null;

app.on('ready', function(){
  // image is null, so image will not be shown in menu bar
  // so click around on the system menu bar to locate the space where the tray icon is
  appIcon = new Tray(null);
  
  var contextMenu = Menu.buildFromTemplate([
    { label: 'Item1', type: 'radio' },
    { label: 'Item2', type: 'radio' },
    { label: 'Item3', type: 'radio', checked: true },
    { label: 'Item4', type: 'radio' }
  ]);
  
  appIcon.setToolTip('This is my application.');
  appIcon.setContextMenu(contextMenu);

  appIcon.on('drag-enter', function() {
    console.log('drag-enter!');
  });

  appIcon.on('drag-leave', function() {
    console.log('drag-leave!');
  });

  appIcon.on('drag-end', function() {
    console.log('drag-end!');
  });

  appIcon.on('drop', function() {
    console.log('drop!');
  });
});

Also, this is referenced in this atom/electron pull request.