window/utils

Add-ons using the techniques described in this document are considered a legacy technology in Firefox. Don't use these techniques to develop new add-ons. Use WebExtensions instead. If you maintain an add-on which uses the techniques described here, consider migrating it to use WebExtensions.

From Firefox 53 onwards, no new legacy add-ons will be accepted on addons.mozilla.org (AMO).

From Firefox 57 onwards, WebExtensions will be the only supported extension type, and Firefox will not load other types.

Even before Firefox 57, changes coming up in the Firefox platform will break many legacy extensions. These changes include multiprocess Firefox (e10s), sandboxing, and multiple content processes. Legacy extensions that are affected by these changes should migrate to WebExtensions if they can. See the "Compatibility Milestones" document for more.

A wiki page containing resources, migration paths, office hours, and more, is available to help developers transition to the new technologies.

Unstable

Note that this module includes functions that give you direct access to web content. These functions are not safe to call in multiprocess Firefox. See Multiprocess Firefox and the SDK for more details.

Functions for working with browser windows.

Usage

Private windows

With this module your add-on will see private browser windows even if it has not explicitly opted into private browsing, so you need to take care not to store any user data derived from private browser windows.

The exception is the windows() function which returns an array of currently opened windows. Private windows will not be included in this list if your add-on has not opted into private browsing.

To learn more about private windows, how to opt into private browsing, and how to support private browsing, refer to the documentation for the private-browsing module.

Globals

Functions

getMostRecentBrowserWindow()

Get the topmost browser window, as an nsIDOMWindow instance.

Returns

nsIDOMWindow: the topmost browser window.

getInnerId(window)

Returns the ID of the specified window's current inner window. This function wraps nsIDOMWindowUtils.currentInnerWindowID.

Parameters

window : nsIDOMWindow
The window whose inner window we are interested in.

Returns

ID: the given window's ID.

getOuterId(window)

Returns the ID of the specified window's outer window. This function wraps nsIDOMWindowUtils.outerWindowID.

Parameters

window : nsIDOMWindow
The window whose outer window we are interested in.

Returns

ID: the outer window's ID.

getXULWindow(window)

Returns the nsIXULWindow for the given nsIDOMWindow:

var { Ci } = require('chrome');
var utils = require('sdk/window/utils');
var active = utils.getMostRecentBrowserWindow();
active instanceof Ci.nsIXULWindow // => false
utils.getXULWindow(active) instanceof Ci.nsIXULWindow // => true
Parameters

window : nsIDOMWindow

Returns

nsIXULWindow

getBaseWindow(window)

Returns the nsIBaseWindow for the given nsIDOMWindow:

var { Ci } = require('chrome');
var utils = require('sdk/window/utils');
var active = utils.getMostRecentBrowserWindow();
active instanceof Ci.nsIBaseWindow // => false
utils.getBaseWindow(active) instanceof Ci.nsIBaseWindow // => true
Parameters

window : nsIDOMWindow

Returns

nsIBaseWindow

getToplevelWindow(window)

Returns the toplevel nsIDOMWindow for the given child nsIDOMWindow:

var { Ci } = require('chrome');
var utils = require('sdk/window/utils');
var browserWindow = utils.getMostRecentBrowserWindow();
var window = browserWindow.content; // `window` object for the current webpage
utils.getToplevelWindow(window) == browserWindow // => true
Parameters

window : nsIDOMWindow

Returns

nsIDOMWindow

getWindowDocShell(window)

Returns the nsIDocShell for the tabbrowser element.

Parameters

window : nsIDOMWindow

Returns

nsIDocShell

getWindowLoadingContext(window)

Returns the nsILoadContext.

Parameters

window : nsIDOMWindow

Returns

nsILoadContext

open(uri, options)

This function is used to open top level (application) windows. It takes the uri of the window document as its first argument and an optional hash of options as its second argument.

var { open } = require('sdk/window/utils');
var window = open('data:text/html,Hello Window');

This function wraps nsIWindowWatcher.openWindow.

Parameters

uri : string
URI of the document to be loaded into the window.  Only chrome, resource, and data schemes are accepted.

options : object
Options for the function, with the following properties:

Name Type  
parent nsIDOMWindow Parent for the new window. Optional, defaults to null.
name string Name that is assigned to the window. Optional, defaults to null.
features object

Map of features to set for the window, defined like this: { width: 10, height: 15, chrome: true }.

See the window.open features documentation for more details.

Optional, defaults to an empty map: {}.

var { open } = require('sdk/window/utils');
var window = open('data:text/html,Hello Window', {
  name: 'jetpack window',
  features: {
    width: 200,
    height: 50,
    popup: true
  }
});
args object Extra argument(s) to be attached to the new window as the window.arguments property.

Returns

nsIDOMWindow

openDialog(options)

Opens a top level window and returns its nsIDOMWindow representation. This is the same as open, but you can supply more features. It wraps window.openDialog.

Parameters

options : object
Options for the function, with the following properties:

Name Type  
url string URI of the document to be loaded into the window. Defaults to "chrome://browser/content/browser.xul".
name string Optional name that is assigned to the window. Defaults to "_blank".
features string

Map of features to set for the window, defined like: { width: 10, height: 15, chrome: true }.

For the set of features you can set, see the window.openDialog documentation.

Optional, defaults to: 'chrome,all,dialog=no'.

args object Extra argument(s) to be attached to the new window as the window.arguments property.
Returns

nsIDOMWindow

windows()

Returns an array of all currently opened windows. Note that these windows may still be loading.

In order to see private windows in this list, your add-on must have opted into private browsing and you must include the includePrivate key in the list of options:

  var allWindows = window_utils.windows(null, {includePrivate:true});
Parameters

type : string
String identifying the type of window to return. This is passed directly into nsIWindowMediator.getEnumerator(), so its possible values are the same as those expected by that function. In particular:

  • null: get all window types
  • navigator:browser: get "normal" browser windows
  • devtools:scratchpad: get Scratchpad windows
  • navigator:view-source: get view source windows

If you're not also passing options, you can omit this, and it's the same as passing null.

options : object
Options object containing the following property:

Name Type  
includePrivate boolean Whether to include private windows. Defaults to false. The add-on must also have opted into private windows for this to have an effect.
Returns

Array: array of nsIDOMWindow instances.

isDocumentLoaded(window)

Check if the given window's document is completely loaded. This means that its "load" event has been fired and all content is loaded, including the whole DOM document, images, and any other sub-resources.

Parameters

window : nsIDOMWindow

Returns

boolean: true if the document is completely loaded.

isBrowser(window)

Returns true if the given window is a Firefox browser window: that is, its document has a "windowtype" of "chrome://browser/content/browser.xul".

Parameters

window : nsIDOMWindow

Returns

boolean

getWindowTitle(window)

Get the title of the document hosted by the given window

Parameters

window: nsIDOMWindow

Returns

string: this document's title.

isXULBrowser(window)

Returns true if the given window is a XUL window.

Parameters

window : nsIDOMWindow

Returns

boolean

getFocusedWindow()

Gets the child window within the topmost browser window that is focused. See nsIFocusManager for more details.

Returns

nsIDOMWindow

getFocusedElement()

Get the element that is currently focused. This will always be an element within the document loaded in the focused window, or null if no element in that document is focused.

Returns

nsIDOMElement

getFrames(window)

Get the frames contained by the given window.

Parameters

window : nsIDOMWindow

Returns

array: array of frames.
 

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 Contributors to this page: wbamberg, Makyen, The_8472, Davidsickmiller, jsantell
 Last updated by: wbamberg,