gecko/dom/base/BrowserElementParent.js

166 lines
5.3 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;
Cu.import("resource://gre/modules/XPCOMUtils.jsm");
const NS_PREFBRANCH_PREFCHANGE_TOPIC_ID = "nsPref:changed";
const BROWSER_FRAMES_ENABLED_PREF = "dom.mozBrowserFramesEnabled";
function debug(msg) {
//dump("BrowserElementParent - " + msg + "\n");
}
/**
* The BrowserElementParent implements one half of <iframe mozbrowser>.
* (The other half is, unsurprisingly, BrowserElementChild.)
*
* We detect windows and docshells contained inside <iframe mozbrowser>s and
* inject script to listen for certain events in the child. We then listen to
* messages from the child script and take appropriate action here.
*/
function BrowserElementParent() {}
BrowserElementParent.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() {
debug("_init");
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()) {
var prefs = Cc["@mozilla.org/preferences-service;1"].getService(Ci.nsIPrefBranch);
prefs.addObserver(BROWSER_FRAMES_ENABLED_PREF, this, /* ownsWeak = */ true);
return;
}
this._initialized = true;
var os = Cc["@mozilla.org/observer-service;1"].getService(Ci.nsIObserverService);
os.addObserver(this, 'remote-browser-frame-shown', /* ownsWeak = */ true);
os.addObserver(this, 'in-process-browser-frame-shown', /* ownsWeak = */ true);
},
_browserFramesPrefEnabled: function() {
var prefs = Cc["@mozilla.org/preferences-service;1"].getService(Ci.nsIPrefBranch);
try {
return prefs.getBoolPref(BROWSER_FRAMES_ENABLED_PREF);
}
catch(e) {
return false;
}
},
_observeInProcessBrowserFrameShown: function(frameLoader, data) {
debug("In-process browser frame shown " + frameLoader);
this._setUpMessageManagerListeners(frameLoader, data);
},
_observeRemoteBrowserFrameShown: function(frameLoader, data) {
debug("Remote browser frame shown " + frameLoader);
this._setUpMessageManagerListeners(frameLoader, data);
},
_setUpMessageManagerListeners: function(frameLoader, data) {
let frameElement = frameLoader.QueryInterface(Ci.nsIFrameLoader).ownerElement;
if (!frameElement) {
debug("No frame element?");
return;
}
let mm = frameLoader.messageManager;
// Messages we receive are handled by functions with parameters
// (frameElement, data), where |data| is the message manager's data object.
let self = this;
function addMessageListener(msg, handler) {
mm.addMessageListener('browser-element-api:' + msg, handler.bind(self, frameElement));
}
addMessageListener("hello", this._recvHello);
addMessageListener("locationchange", this._fireEventFromMsg);
addMessageListener("loadstart", this._fireEventFromMsg);
addMessageListener("loadend", this._fireEventFromMsg);
addMessageListener("titlechange", this._fireEventFromMsg);
addMessageListener("iconchange", this._fireEventFromMsg);
addMessageListener("get-mozapp", this._sendAppState);
mm.loadFrameScript("chrome://global/content/BrowserElementChild.js",
/* allowDelayedLoad = */ true);
},
_recvHello: function(frameElement, data) {
debug("recvHello " + frameElement);
},
/**
* Fire either a vanilla or a custom event, depending on the contents of
* |data|.
*/
_fireEventFromMsg: function(frameElement, data) {
let name = data.name;
let detail = data.json;
debug('fireEventFromMsg: ' + name + ' ' + detail);
let evtName = name.substring('browser-element-api:'.length);
let win = frameElement.ownerDocument.defaultView;
let evt;
// This will have to change if we ever want to send a CustomEvent with null
// detail. For now, it's OK.
if (detail !== undefined && detail !== null) {
evt = new win.CustomEvent('mozbrowser' + evtName, {detail: detail});
}
else {
evt = new win.Event('mozbrowser' + evtName);
}
frameElement.dispatchEvent(evt);
},
_sendAppState: function(frameElement, data) {
return frameElement.hasAttribute('mozapp');
},
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, data);
break;
case 'in-process-browser-frame-shown':
this._observeInProcessBrowserFrameShown(subject, data);
break;
case 'content-document-global-created':
this._observeContentGlobalCreated(subject);
break;
}
},
};
var NSGetFactory = XPCOMUtils.generateNSGetFactory([BrowserElementParent]);