gecko-dev/dom/browser-element/BrowserElementParent.js
Fabrice Desré affdca43f1 Bug 835548 - Refactor BrowserElementParent.js into a .js and .jsm, and speed up message registration. r=jlebar
--HG--
rename : dom/browser-element/BrowserElementParent.js => dom/browser-element/BrowserElementParent.jsm
2013-01-30 14:22:54 -08:00

120 lines
3.8 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";
let Cu = Components.utils;
let Ci = Components.interfaces;
let Cc = Components.classes;
let Cr = Components.results;
Cu.import("resource://gre/modules/Services.jsm");
Cu.import("resource://gre/modules/XPCOMUtils.jsm");
Cu.import("resource://gre/modules/BrowserElementParent.jsm");
const NS_PREFBRANCH_PREFCHANGE_TOPIC_ID = "nsPref:changed";
const BROWSER_FRAMES_ENABLED_PREF = "dom.mozBrowserFramesEnabled";
function debug(msg) {
//dump("BrowserElementParent.js - " + msg + "\n");
}
/**
* BrowserElementParent implements one half of <iframe mozbrowser>. (The other
* half is, unsurprisingly, BrowserElementChild.)
*
* BrowserElementParentFactory detects when we create a windows or docshell
* contained inside a <iframe mozbrowser> and creates a BrowserElementParent
* object for that window.
*
* It creates a BrowserElementParent that injects script to listen for
* certain event.
*/
function BrowserElementParentFactory() {
this._initialized = false;
}
BrowserElementParentFactory.prototype = {
classID: Components.ID("{ddeafdac-cb39-47c4-9cb8-c9027ee36d26}"),
QueryInterface: XPCOMUtils.generateQI([Ci.nsIObserver,
Ci.nsISupportsWeakReference]),
/**
* Called on app startup, and also when the browser frames enabled pref is
* changed.
*/
_init: function() {
if (this._initialized) {
return;
}
// If the pref is disabled, do nothing except wait for the pref to change.
// (This is important for tests, if nothing else.)
if (!this._browserFramesPrefEnabled()) {
Services.prefs.addObserver(BROWSER_FRAMES_ENABLED_PREF, this, /* ownsWeak = */ true);
return;
}
debug("_init");
this._initialized = true;
// Maps frame elements to BrowserElementParent objects. We never look up
// anything in this map; the purpose is to keep the BrowserElementParent
// alive for as long as its frame element lives.
this._bepMap = new WeakMap();
Services.obs.addObserver(this, 'remote-browser-frame-shown', /* ownsWeak = */ true);
Services.obs.addObserver(this, 'in-process-browser-or-app-frame-shown', /* ownsWeak = */ true);
},
_browserFramesPrefEnabled: function() {
try {
return Services.prefs.getBoolPref(BROWSER_FRAMES_ENABLED_PREF);
}
catch(e) {
return false;
}
},
_observeInProcessBrowserFrameShown: function(frameLoader) {
debug("In-process browser frame shown " + frameLoader);
this._createBrowserElementParent(frameLoader, /* hasRemoteFrame = */ false);
},
_observeRemoteBrowserFrameShown: function(frameLoader) {
debug("Remote browser frame shown " + frameLoader);
this._createBrowserElementParent(frameLoader, /* hasRemoteFrame = */ true);
},
_createBrowserElementParent: function(frameLoader, hasRemoteFrame) {
let frameElement = frameLoader.QueryInterface(Ci.nsIFrameLoader).ownerElement;
this._bepMap.set(frameElement, BrowserElementParentBuilder.create(frameLoader, hasRemoteFrame));
},
observe: function(subject, topic, data) {
switch(topic) {
case 'app-startup':
this._init();
break;
case NS_PREFBRANCH_PREFCHANGE_TOPIC_ID:
if (data == BROWSER_FRAMES_ENABLED_PREF) {
this._init();
}
break;
case 'remote-browser-frame-shown':
this._observeRemoteBrowserFrameShown(subject);
break;
case 'in-process-browser-or-app-frame-shown':
this._observeInProcessBrowserFrameShown(subject);
break;
case 'content-document-global-created':
this._observeContentGlobalCreated(subject);
break;
}
},
};
this.NSGetFactory = XPCOMUtils.generateNSGetFactory([BrowserElementParentFactory]);