gecko-dev/toolkit/modules/HiddenFrame.jsm

117 строки
3.4 KiB
JavaScript

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
"use strict";
var EXPORTED_SYMBOLS = ["HiddenFrame"];
const {PromiseUtils} = ChromeUtils.import("resource://gre/modules/PromiseUtils.jsm");
const {Services} = ChromeUtils.import("resource://gre/modules/Services.jsm");
const XUL_PAGE = "chrome://global/content/win.xul";
const gAllHiddenFrames = new WeakSet();
let cleanupRegistered = false;
function ensureCleanupRegistered() {
if (!cleanupRegistered) {
cleanupRegistered = true;
Services.obs.addObserver(function() {
for (let hiddenFrame of ChromeUtils.nondeterministicGetWeakSetKeys(gAllHiddenFrames)) {
hiddenFrame.destroy();
}
}, "xpcom-shutdown");
}
}
/**
* An hidden frame object. It takes care of creating a windowless browser and
* passing the window containing a blank XUL <window> back.
*/
function HiddenFrame() {
}
HiddenFrame.prototype = {
_frame: null,
_browser: null,
_listener: null,
_webProgress: null,
_deferred: null,
/**
* Gets the |contentWindow| of the hidden frame. Creates the frame if needed.
* @returns Promise Returns a promise which is resolved when the hidden frame has finished
* loading.
*/
get() {
if (!this._deferred) {
this._deferred = PromiseUtils.defer();
this._create();
}
return this._deferred.promise;
},
/**
* Fetch a sync ref to the window inside the frame (needed for the add-on SDK).
*/
getWindow() {
this.get();
return this._browser.document.ownerGlobal;
},
destroy() {
if (this._browser) {
if (this._listener) {
this._webProgress.removeProgressListener(this._listener);
this._listener = null;
this._webProgress = null;
}
this._frame = null;
this._deferred = null;
gAllHiddenFrames.delete(this);
this._browser.close();
this._browser = null;
}
},
_create() {
ensureCleanupRegistered();
this._browser = Services.appShell.createWindowlessBrowser(true);
this._browser.QueryInterface(Ci.nsIInterfaceRequestor);
gAllHiddenFrames.add(this);
this._webProgress = this._browser.getInterface(Ci.nsIWebProgress);
this._listener = {
QueryInterface: ChromeUtils.generateQI([
Ci.nsIWebProgressListener, Ci.nsIWebProgressListener2,
Ci.nsISupportsWeakReference]),
};
this._listener.onStateChange = (wbp, request, stateFlags, status) => {
if (!request) {
return;
}
if (stateFlags & Ci.nsIWebProgressListener.STATE_STOP) {
this._webProgress.removeProgressListener(this._listener);
this._listener = null;
this._webProgress = null;
// Get the window reference via the document.
this._frame = this._browser.document.ownerGlobal;
this._deferred.resolve(this._frame);
}
};
this._webProgress.addProgressListener(this._listener, Ci.nsIWebProgress.NOTIFY_STATE_DOCUMENT);
let docShell = this._browser.docShell;
let systemPrincipal = Services.scriptSecurityManager.getSystemPrincipal();
docShell.createAboutBlankContentViewer(systemPrincipal);
docShell.useGlobalHistory = false;
let loadURIOptions = {
triggeringPrincipal: systemPrincipal,
};
this._browser.loadURI(XUL_PAGE, loadURIOptions);
},
};