In a Nutshell: I am implementing a single-page website using Electron and encountered the common issue of jQuery not being globally accessible. So I simplified the problem by using the quick start example in the following in order to figure it out, but I cannot make sense of it.
As you can see, I have simply added the following code to the end of my main.js file to check if the issue is resolved:
$(document).ready(function () {
console.log("hi");
});
This is the complete code of my main.js file:
// main.js
// Modules to control application life and create native browser window
const { app, BrowserWindow } = require("electron");
const path = require("path");
function createWindow() {
// Create the browser window.
const mainWindow = new BrowserWindow({
width: 800,
height: 600,
webPreferences: {
preload: path.join(__dirname, "preload.js"),
nodeIntegration: true,
webSecurity: true,
},
});
// and load the index.html of the app.
mainWindow.loadFile("index.html");
// Open the DevTools.
// mainWindow.webContents.openDevTools()
}
// 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();
app.on("activate", function () {
// On macOS it's common to re-create a window in the app when the
// dock icon is clicked and there are no other windows open.
if (BrowserWindow.getAllWindows().length === 0) 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();
});
// 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.
$(document).ready(function () {
console.log("hi");
});
I am loading the following HTML code into my BrowserWindow:
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<!-- https://developer.mozilla.org/en-US/docs/Web/HTTP/CSP -->
<!--This was added otherwise "window.jQuery = window.$ = require('jquery');" will not be executed-->
<meta http-equiv="Content-Security-Policy" content="default-src *; style-src 'self' http://* 'unsafe-inline'; script-src 'self' http://* 'unsafe-inline' 'unsafe-eval'" />
<title>Hello World!</title>
</head>
<body>
<h1>Hello World!</h1>
We are using Node.js <span id="node-version"></span>,
Chromium <span id="chrome-version"></span>,
and Electron <span id="electron-version"></span>.
<script src="node_modules/jquery/dist/jquery.min.js"></script>
<script>window.jQuery = window.$ = require('jquery');</script>
<script src="./renderer.js"></script>
</body>
</html>
Below script is attached to the BrowserWindow as a preload script as advised by the Electron documentation:
// Preload.js
// All of the Node.js APIs are available in the preload process.
// It has the same sandbox as a Chrome extension.
window.addEventListener("DOMContentLoaded", () => {
const replaceText = (selector, text) => {
const element = document.getElementById(selector);
if (element) element.innerText = text;
};
for (const type of ["chrome", "node", "electron"]) {
replaceText(`${type}-version`, process.versions[type]);
}
});
Last but not least, this is the package.json configuration file of the quick start project:
{
"name": "electron-quick-start",
"version": "1.0.0",
"description": "A minimal Electron application",
"main": "main.js",
"scripts": {
"start": "electron ."
},
"repository": "https://github.com/electron/electron-quick-start",
"keywords": [
"Electron",
"quick",
"start",
"tutorial",
"demo"
],
"author": "GitHub",
"license": "CC0-1.0",
"devDependencies": {
"electron": "^9.0.2"
},
"dependencies": {
"jquery": "^3.5.1"
}
}
However, each time I run the app, I get the following error prompt:
This error is also shown in my app's Powershell output (I have only redacted the full directory path):
App threw an error during load ReferenceError: $ is not defined at Object.<anonymous> (...directory\0masterproject\main.js:48:1) at Module._compile (internal/modules/cjs/loader.js:967:30) at Object.Module._extensions..js (internal/modules/cjs/loader.js:1004:10) at Module.load (internal/modules/cjs/loader.js:815:32) at Module._load (internal/modules/cjs/loader.js:727:14) at Function.Module._load (electron/js2c/asar.js:738:28) at loadApplicationPackage (...directory\0masterproject\node_modules\electron\dist\resources\default_app.asar\main.js:109:16) at Object.<anonymous> (...directory\0masterproject\node_modules\electron\dist\resources\default_app.asar\main.js:155:9) at Module._compile (internal/modules/cjs/loader.js:967:30) at Object.Module._extensions..js (internal/modules/cjs/loader.js:1004:10) PS ...directory\0masterproject> npm start
However, when I close this window and check the BrowserWindow's console, I do not see any error, but no "hi" output either.
Before I ran into this issue, I had the problem that require () was not defined, which I have resolved by adding
<script src="node_modules/jquery/dist/jquery.min.js"></script>
before my jQuery code:
<script>window.jQuery = window.$ = require('jquery');</script>
I found this solution in this article; I have already tried this example in Electron's documentation but to no avail.
Please let me know of there is any information missing.
