未捕获的类型错误：无法读取未定义的属性“on”。 我也尝试重新安装电子

Question

I am not able to remove an error mentioned:

" Uncaught TypeError: Cannot read property 'on' of undefined "

I have tried to reinstall electron as well but still getting the same error.

 const electron = require('electron');
 const {BrowserWindow, Menu} = require('electron');
 var app = electron.app;
 const conn = require('mysql');
 const path = require('path');
 const url = require('url');
 var mainWindow;
 app.on('ready', function () {
     mainWindow = new BrowserWindow({ width: 1024, height: 768, 
     backgroundcolor: 'black' });
        mainWindow.loadURL(url.format({
            pathname: 'dashboard.html',
            protocol: 'file:',
            slashes: true
       }));
     mainWindow.webContents.openDevTools();
     mainWindow.setProgressBar(1);
});

Answer 1

"TypeError: Cannot read property 'on' of undefined" This means 'app' object has not been loaded properly from 'electron' module and the 'app.on()' method on 8th line, it has been called on undefined object 'app'.

Please try these possible solutions.

1. Replace

   const electron = require('electron'); const {BrowserWindow, Menu} = require('electron'); var app = electron.app;

   with

   var app = require('electron').app; const {BrowserWindow, Menu} = require('electron');

2. In Package.json file edit/add this line specifying the starting point for an application.

    "script":{"start": "electron ."}

edit:

May be you have the npm electron module installed somewhere in your system(globally), it overrides the builtin electron module. You can find out the path of it by logging out

 require.resolve('electron').