electron/docs/api/frameless-window.md
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Co-Authored-By: Mark Lee <malept@users.noreply.github.com>

Co-authored-by: Mark Lee <malept@users.noreply.github.com>
Co-authored-by: John Kleinschmidt <jkleinsc@github.com>
2020-03-31 13:06:25 +09:00

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Frameless Window

Open a window without toolbars, borders, or other graphical "chrome".

A frameless window is a window that has no chrome, the parts of the window, like toolbars, that are not a part of the web page. These are options on the BrowserWindow class.

Create a frameless window

To create a frameless window, you need to set frame to false in BrowserWindow's options:

const { BrowserWindow } = require('electron')
let win = new BrowserWindow({ width: 800, height: 600, frame: false })
win.show()

Alternatives on macOS

There's an alternative way to specify a chromeless window. Instead of setting frame to false which disables both the titlebar and window controls, you may want to have the title bar hidden and your content extend to the full window size, yet still preserve the window controls ("traffic lights") for standard window actions. You can do so by specifying the titleBarStyle option:

hidden

Results in a hidden title bar and a full size content window, yet the title bar still has the standard window controls (“traffic lights”) in the top left.

const { BrowserWindow } = require('electron')
let win = new BrowserWindow({ titleBarStyle: 'hidden' })
win.show()

hiddenInset

Results in a hidden title bar with an alternative look where the traffic light buttons are slightly more inset from the window edge.

const { BrowserWindow } = require('electron')
let win = new BrowserWindow({ titleBarStyle: 'hiddenInset' })
win.show()

customButtonsOnHover

Uses custom drawn close, and miniaturize buttons that display when hovering in the top left of the window. The fullscreen button is not available due to restrictions of frameless windows as they interface with Apple's macOS window masks. These custom buttons prevent issues with mouse events that occur with the standard window toolbar buttons. This option is only applicable for frameless windows.

const { BrowserWindow } = require('electron')
let win = new BrowserWindow({ titleBarStyle: 'customButtonsOnHover', frame: false })
win.show()

Transparent window

By setting the transparent option to true, you can also make the frameless window transparent:

const { BrowserWindow } = require('electron')
let win = new BrowserWindow({ transparent: true, frame: false })
win.show()

Limitations

  • You can not click through the transparent area. We are going to introduce an API to set window shape to solve this, see our issue for details.
  • Transparent windows are not resizable. Setting resizable to true may make a transparent window stop working on some platforms.
  • The blur filter only applies to the web page, so there is no way to apply blur effect to the content below the window (i.e. other applications open on the user's system).
  • On Windows operating systems, transparent windows will not work when DWM is disabled.
  • On Linux, users have to put --enable-transparent-visuals --disable-gpu in the command line to disable GPU and allow ARGB to make transparent window, this is caused by an upstream bug that alpha channel doesn't work on some NVidia drivers on Linux.
  • On Mac, the native window shadow will not be shown on a transparent window.

Click-through window

To create a click-through window, i.e. making the window ignore all mouse events, you can call the win.setIgnoreMouseEvents(ignore) API:

const { BrowserWindow } = require('electron')
let win = new BrowserWindow()
win.setIgnoreMouseEvents(true)

Forwarding

Ignoring mouse messages makes the web page oblivious to mouse movement, meaning that mouse movement events will not be emitted. On Windows operating systems an optional parameter can be used to forward mouse move messages to the web page, allowing events such as mouseleave to be emitted:

let win = require('electron').remote.getCurrentWindow()
let el = document.getElementById('clickThroughElement')
el.addEventListener('mouseenter', () => {
  win.setIgnoreMouseEvents(true, { forward: true })
})
el.addEventListener('mouseleave', () => {
  win.setIgnoreMouseEvents(false)
})

This makes the web page click-through when over el, and returns to normal outside it.

Draggable region

By default, the frameless window is non-draggable. Apps need to specify -webkit-app-region: drag in CSS to tell Electron which regions are draggable (like the OS's standard titlebar), and apps can also use -webkit-app-region: no-drag to exclude the non-draggable area from the draggable region. Note that only rectangular shapes are currently supported.

Note: -webkit-app-region: drag is known to have problems while the developer tools are open. See this GitHub issue for more information including a workaround.

To make the whole window draggable, you can add -webkit-app-region: drag as body's style:

<body style="-webkit-app-region: drag">
</body>

And note that if you have made the whole window draggable, you must also mark buttons as non-draggable, otherwise it would be impossible for users to click on them:

button {
  -webkit-app-region: no-drag;
}

If you're only setting a custom titlebar as draggable, you also need to make all buttons in titlebar non-draggable.

Text selection

In a frameless window the dragging behavior may conflict with selecting text. For example, when you drag the titlebar you may accidentally select the text on the titlebar. To prevent this, you need to disable text selection within a draggable area like this:

.titlebar {
  -webkit-user-select: none;
  -webkit-app-region: drag;
}

Context menu

On some platforms, the draggable area will be treated as a non-client frame, so when you right click on it a system menu will pop up. To make the context menu behave correctly on all platforms you should never use a custom context menu on draggable areas.