I've been trying for a while. I followed the / and with relative success I managed to make an "app" using Bootstrap and Jquery.
But now, I'm trying to use Electron API methods but with no success.
I created a Browser Window, and within that Window I added a new JS file. Within that file, I'm trying to call printToPDF method here:
It just doesn't work and the console logs the following:
Uncaught ReferenceError: mainWindow is not defined
The code goes as this:
main.js
const electron = require('electron')
const app = electron.app
const BrowserWindow = electron.BrowserWindow
let mainWindow
function createWindow () {
mainWindow = new BrowserWindow({width: 800, height: 600})
mainWindow.loadURL(`file://${__dirname}/index.html`)
mainWindow.webContents.openDevTools()
mainWindow.on('closed', function () {
mainWindow = null
})
}
app.on('ready', createWindow)
app.on('window-all-closed', function () {
if (process.platform !== 'darwin') {
app.quit()
}
})
app.on('activate', function () {
if (mainWindow === null) {
createWindow()
}
})
index.html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Hello World!</title>
<link rel="stylesheet" type="text/css" href="./css/bootstrap.min.css">
</head>
<body>
</body>
<script>window.$ = window.jQuery = require('jquery');</script>
<script type="text/javascript" src="./js/bootstrap.min.js"></script>
<script>
require('./app.js');
</script>
</html>
app.js
$(function() {
mainWindow.webContents.printToPDF();
});
I've been trying http://electron.atom.io for a while. I followed the http://electron.atom.io/docs/tutorial/quick-start/ and with relative success I managed to make an "app" using Bootstrap and Jquery.
But now, I'm trying to use Electron API methods but with no success.
I created a Browser Window, and within that Window I added a new JS file. Within that file, I'm trying to call printToPDF method here: http://electron.atom.io/docs/api/web-contents/#contentsprinttopdfoptions-callback
It just doesn't work and the console logs the following:
Uncaught ReferenceError: mainWindow is not defined
The code goes as this:
main.js
const electron = require('electron')
const app = electron.app
const BrowserWindow = electron.BrowserWindow
let mainWindow
function createWindow () {
mainWindow = new BrowserWindow({width: 800, height: 600})
mainWindow.loadURL(`file://${__dirname}/index.html`)
mainWindow.webContents.openDevTools()
mainWindow.on('closed', function () {
mainWindow = null
})
}
app.on('ready', createWindow)
app.on('window-all-closed', function () {
if (process.platform !== 'darwin') {
app.quit()
}
})
app.on('activate', function () {
if (mainWindow === null) {
createWindow()
}
})
index.html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Hello World!</title>
<link rel="stylesheet" type="text/css" href="./css/bootstrap.min.css">
</head>
<body>
</body>
<script>window.$ = window.jQuery = require('jquery');</script>
<script type="text/javascript" src="./js/bootstrap.min.js"></script>
<script>
require('./app.js');
</script>
</html>
app.js
$(function() {
mainWindow.webContents.printToPDF();
});
-
in your served html/js you don't have access to anything in
main.js. You can make a function inapp.jsthat emits an event, then in yourmain.jsyou can listen for that event and callmainWindow.webContents.printToPDF();there when the event gets triggered. – Simon Hänisch Commented Sep 28, 2016 at 11:38
1 Answer
Reset to default 5Take a look at the ipc modules, ipcMain and ipcRenderer. The ipc module allows you to send and receive synchronous and asynchronous messages between the main and the render process.
Here the print to PDF example from the ELECTRON API DEMOS app.
Renderer Process
const ipc = require('electron').ipcRenderer
const printPDFBtn = document.getElementById('print-pdf')
printPDFBtn.addEventListener('click', function (event) {
ipc.send('print-to-pdf')
})
ipc.on('wrote-pdf', function (event, path) {
const message = `Wrote PDF to: ${path}`
document.getElementById('pdf-path').innerHTML = message
})
Main Process
const fs = require('fs')
const os = require('os')
const path = require('path')
const electron = require('electron')
const BrowserWindow = electron.BrowserWindow
const ipc = electron.ipcMain
const shell = electron.shell
ipc.on('print-to-pdf', function (event) {
const pdfPath = path.join(os.tmpdir(), 'print.pdf')
const win = BrowserWindow.fromWebContents(event.sender)
// Use default printing options
win.webContents.printToPDF({}, function (error, data) {
if (error) throw error
fs.writeFile(pdfPath, data, function (error) {
if (error) {
throw error
}
shell.openExternal('file://' + pdfPath)
event.sender.send('wrote-pdf', pdfPath)
})
})
})