Plusb Preco c4a2329665 📝 Update docs styles

* Adjust line length to `80`
* Change platform marker `*` to `_`
* Enhance a note section

[ci skip]

2016-03-30 10:57:42 +09:00

4.9 KiB

Raw Blame History

Electron FAQ

When will Electron upgrade to latest Chrome?

The Chrome version of Electron is usually bumped within one or two weeks after a new stable Chrome version gets released.

Also we only use stable channel of Chrome. If an important fix is in beta or dev channel, we will back-port it.

When will Electron upgrade to latest Node.js?

When a new version of Node.js gets released, we usually wait for about a month before upgrading the one in Electron. So we can avoid getting affected by bugs introduced in new Node.js versions, which happens very often.

New features of Node.js are usually brought by V8 upgrades, since Electron is using the V8 shipped by Chrome browser, the shiny new JavaScript feature of a new Node.js version is usually already in Electron.

To share data between web pages (the renderer processes) the simplest way is to use HTML5 APIs which are already available in browsers. Good candidates are Storage API, localStorage, sessionStorage, and IndexedDB.

Or you can use the IPC system, which is specific to Electron, to store objects in the main process as a global variable, and then to access them from the renderers through the remote module:

// In the main process.
global.sharedObject = {
  someProperty: 'default value'
};

// In page 1.
require('remote').getGlobal('sharedObject').someProperty = 'new value';

// In page 2.
console.log(require('remote').getGlobal('sharedObject').someProperty);

My app's window/tray disappeared after a few minutes.

This happens when the variable which is used to store the window/tray gets garbage collected.

If you encounter this problem, the following articles may prove helpful:

If you want a quick fix, you can make the variables global by changing your code from this:

app.on('ready', function() {
  var tray = new Tray('/path/to/icon.png');
})

to this:

var tray = null;
app.on('ready', function() {
  tray = new Tray('/path/to/icon.png');
})

I can not use jQuery/RequireJS/Meteor/AngularJS in Electron.

Due to the Node.js integration of Electron, there are some extra symbols inserted into the DOM like module, exports, require. This causes problems for some libraries since they want to insert the symbols with the same names.

To solve this, you can turn off node integration in Electron:

// In the main process.
var mainWindow = new BrowserWindow({
  webPreferences: {
    nodeIntegration: false
  }
});

But if you want to keep the abilities of using Node.js and Electron APIs, you have to rename the symbols in the page before including other libraries:

<head>
<script>
window.nodeRequire = require;
delete window.require;
delete window.exports;
delete window.module;
</script>
<script type="text/javascript" src="jquery.js"></script>
</head>

`require('electron').xxx` is undefined.

When using Electron's built-in module you might encounter an error like this:

> require('electron').webFrame.setZoomFactor(1.0);
Uncaught TypeError: Cannot read property 'setZoomLevel' of undefined

This is because you have the npm electron module installed either locally or globally, which overrides Electron's built-in module.

To verify whether you are using the correct built-in module, you can print the path of the electron module:

console.log(require.resolve('electron'));

and then check if it is in the following form:

"/path/to/Electron.app/Contents/Resources/atom.asar/renderer/api/lib/exports/electron.js"

If it is something like node_modules/electron/index.js, then you have to either remove the npm electron module, or rename it.

npm uninstall electron
npm uninstall -g electron

However if your are using the built-in module but still getting this error, it is very likely you are using the module in the wrong process. For example electron.app can only be used in the main process, while electron.webFrame is only available in renderer processes.

Why is my app's background transparent?

Since Electron 0.37.3, the default user-agent background color is transparent. Simply specify a background color in HTML:

<style type='text/css'>
  html {
    background: white;
  }
</style>

4.9 KiB Raw Blame History