TypeError: Cannot read propert 'on' of undefined.

[omwalhekar]

This happened when I had to close all other windows when we close the main window. Couldn't find a solution to this. The error is for mainWindow.on("closed", function () { app.quit(); });

Below is my code.

const electron = require("electron");
const url = require("url");
const path = require("path");

const { app, BrowserWindow, Menu } = electron;

let mainWindow;
let addWindow;

//Listen for app to be ready
app.on("ready", function () {
  //Create new window
  mainwindow = new BrowserWindow({});

  //Load the html file
  mainwindow.loadURL(
    url.format({
      pathname: path.join(__dirname, "mainWindow.html"),
      protocol: "file:",
      slashes: true,
    })
  );

  // Quit app when closed
  mainWindow.on("closed", function () {
    app.quit();
  });

  //Build the menu from template
  const mainMenu = Menu.buildFromTemplate(mainMenuTemplate);

  //Insert the menu
  Menu.setApplicationMenu(mainMenu);
});

//Handle create add window
function createAddWindow() {
  addWindow = new BrowserWindow({
    width: 300,
    height: 200,
    title: "Add shopping list item",
  });

  //Load the html file
  addWindow.loadURL(
    url.format({
      pathname: path.join(__dirname, "addWindow.html"),
      protocol: "file:",
      slashes: true,
    })
  );
}

//Create menu template
const mainMenuTemplate = [
  {
    label: "File",
    submenu: [
      {
        label: "Add Item",
        click() {
          createAddWindow();
        },
      },
      {
        label: "Clear Items",
      },
      {
        label: "Quit",
        accelerator: process.platform == "darwin" ? "Command+Q" : "Ctrl+Q",
        click() {
          app.quit();
        },
      },
    ],
  },
];

[glebpigulevsky]

@omwalhekar try to read text of your error: TypeError: Cannot read property 'on' of undefined. it means that something that stands before the 'on' method is indefinite. and indeed there is no 'mainwindow', I see only 'mainwindow'