electron/docs/fiddles/native-ui/drag-and-drop/main.js

// Modules to control application life and create native browser window
const { app, BrowserWindow, ipcMain, nativeImage, shell } = require('electron')
// 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: {
      contextIsolation: false,
      nodeIntegration: true
    }
  })

  // 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
  })

  // Open external links in the default browser
  mainWindow.webContents.on('will-navigate', (event, url) => {
    event.preventDefault()
    shell.openExternal(url)
  })
}

// 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.whenReady().then(createWindow)

// Quit when all windows are closed.
app.on('window-all-closed', function () {
  // On macOS 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 macOS it is 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()
  }
})

ipcMain.on('ondragstart', (event, filepath) => {
  const icon = nativeImage.createFromDataURL('data:image/png;base64,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

  event.sender.startDrag({
    file: filepath,
    icon
  })
})

// 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.