gecko/dom/browser-element/BrowserElementParent.js

350 lines
12 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/Services.jsm");
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");
}
/**
* 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.
*
* BrowserElementParent injects script to listen for certain events in the
* child. We then listen to messages from the child script and take
* appropriate action here in the parent.
*/
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()) {
var prefs = Cc["@mozilla.org/preferences-service;1"].getService(Ci.nsIPrefBranch);
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();
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) {
debug("In-process browser frame shown " + frameLoader);
this._createBrowserElementParent(frameLoader);
},
_observeRemoteBrowserFrameShown: function(frameLoader) {
debug("Remote browser frame shown " + frameLoader);
this._createBrowserElementParent(frameLoader);
},
_createBrowserElementParent: function(frameLoader) {
let frameElement = frameLoader.QueryInterface(Ci.nsIFrameLoader).ownerElement;
this._bepMap.set(frameElement, new BrowserElementParent(frameLoader));
},
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-frame-shown':
this._observeInProcessBrowserFrameShown(subject);
break;
case 'content-document-global-created':
this._observeContentGlobalCreated(subject);
break;
}
},
};
function BrowserElementParent(frameLoader) {
debug("Creating new BrowserElementParent object for " + frameLoader);
this._domRequestCounter = 0;
this._pendingDOMRequests = {};
this._frameElement = frameLoader.QueryInterface(Ci.nsIFrameLoader).ownerElement;
if (!this._frameElement) {
debug("No frame element?");
return;
}
this._mm = frameLoader.messageManager;
// Messages we receive are handed to functions which take a (data) argument,
// where |data| is the message manager's data object.
let self = this;
function addMessageListener(msg, handler) {
self._mm.addMessageListener('browser-element-api:' + msg, handler.bind(self));
}
addMessageListener("hello", this._recvHello);
addMessageListener("contextmenu", this._fireCtxMenuEvent);
addMessageListener("locationchange", this._fireEventFromMsg);
addMessageListener("loadstart", this._fireEventFromMsg);
addMessageListener("loadend", this._fireEventFromMsg);
addMessageListener("titlechange", this._fireEventFromMsg);
addMessageListener("iconchange", this._fireEventFromMsg);
addMessageListener("close", this._fireEventFromMsg);
addMessageListener("securitychange", this._fireEventFromMsg);
addMessageListener("get-mozapp-manifest-url", this._sendMozAppManifestURL);
addMessageListener("keyevent", this._fireKeyEvent);
addMessageListener("showmodalprompt", this._handleShowModalPrompt);
addMessageListener('got-screenshot', this._gotDOMRequestResult);
addMessageListener('got-can-go-back', this._gotDOMRequestResult);
addMessageListener('got-can-go-forward', this._gotDOMRequestResult);
function defineMethod(name, fn) {
XPCNativeWrapper.unwrap(self._frameElement)[name] = fn.bind(self);
}
function defineDOMRequestMethod(domName, msgName) {
XPCNativeWrapper.unwrap(self._frameElement)[domName] = self._sendDOMRequest.bind(self, msgName);
}
// Define methods on the frame element.
defineMethod('setVisible', this._setVisible);
defineMethod('goBack', this._goBack);
defineMethod('goForward', this._goForward);
defineDOMRequestMethod('getScreenshot', 'get-screenshot');
defineDOMRequestMethod('getCanGoBack', 'get-can-go-back');
defineDOMRequestMethod('getCanGoForward', 'get-can-go-forward');
}
BrowserElementParent.prototype = {
get _window() {
return this._frameElement.ownerDocument.defaultView;
},
_sendAsyncMsg: function(msg, data) {
this._frameElement.QueryInterface(Ci.nsIFrameLoaderOwner)
.frameLoader
.messageManager
.sendAsyncMessage('browser-element-api:' + msg, data);
},
_recvHello: function(data) {
debug("recvHello");
},
_fireCtxMenuEvent: function(data) {
let evtName = data.name.substring('browser-element-api:'.length);
let detail = data.json;
debug('fireCtxMenuEventFromMsg: ' + evtName + ' ' + detail);
let evt = this._createEvent(evtName, detail);
if (detail.contextmenu) {
var self = this;
XPCNativeWrapper.unwrap(evt.detail).contextMenuItemSelected = function(id) {
self._sendAsyncMsg('fire-ctx-callback', {menuitem: id});
};
}
// The embedder may have default actions on context menu events, so
// we fire a context menu event even if the child didn't define a
// custom context menu
this._frameElement.dispatchEvent(evt);
},
/**
* Fire either a vanilla or a custom event, depending on the contents of
* |data|.
*/
_fireEventFromMsg: function(data) {
let name = data.name.substring('browser-element-api:'.length);
let detail = data.json;
debug('fireEventFromMsg: ' + name + ', ' + detail);
let evt = this._createEvent(name, detail,
/* cancelable = */ false);
this._frameElement.dispatchEvent(evt);
},
_handleShowModalPrompt: function(data) {
// Fire a showmodalprmopt event on the iframe. When this method is called,
// the child is spinning in a nested event loop waiting for an
// unblock-modal-prompt message.
//
// If the embedder calls preventDefault() on the showmodalprompt event,
// we'll block the child until event.detail.unblock() is called.
//
// Otherwise, if preventDefault() is not called, we'll send the
// unblock-modal-prompt message to the child as soon as the event is done
// dispatching.
let detail = data.json;
debug('handleShowPrompt ' + JSON.stringify(detail));
// Strip off the windowID property from the object we send along in the
// event.
let windowID = detail.windowID;
delete detail.windowID;
debug("Event will have detail: " + JSON.stringify(detail));
let evt = this._createEvent('showmodalprompt', detail,
/* cancelable = */ true);
let self = this;
let unblockMsgSent = false;
function sendUnblockMsg() {
if (unblockMsgSent) {
return;
}
unblockMsgSent = true;
// We don't need to sanitize evt.detail.returnValue (e.g. converting the
// return value of confirm() to a boolean); Gecko does that for us.
let data = { windowID: windowID,
returnValue: evt.detail.returnValue };
self._sendAsyncMsg('unblock-modal-prompt', data);
}
XPCNativeWrapper.unwrap(evt.detail).unblock = function() {
sendUnblockMsg();
};
this._frameElement.dispatchEvent(evt);
if (!evt.defaultPrevented) {
// Unblock the inner frame immediately. Otherwise we'll unblock upon
// evt.detail.unblock().
sendUnblockMsg();
}
},
_createEvent: function(evtName, detail, cancelable) {
// 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) {
return new this._window.CustomEvent('mozbrowser' + evtName,
{ bubbles: true,
cancelable: cancelable,
detail: detail });
}
return new this._window.Event('mozbrowser' + evtName,
{ bubbles: true,
cancelable: cancelable });
},
_sendMozAppManifestURL: function(data) {
return this._frameElement.getAttribute('mozapp');
},
/**
* Kick off a DOMRequest in the child process.
*
* We'll fire an event called |msgName| on the child process, passing along
* an object with a single field, id, containing the ID of this request.
*
* We expect the child to pass the ID back to us upon completion of the
* request; see _gotDOMRequestResult.
*/
_sendDOMRequest: function(msgName) {
let id = 'req_' + this._domRequestCounter++;
let req = Services.DOMRequest.createRequest(this._window);
this._pendingDOMRequests[id] = req;
this._sendAsyncMsg(msgName, {id: id});
return req;
},
/**
* Called when the child process finishes handling a DOMRequest. We expect
* data.json to have two fields:
*
* - id: the ID of the DOM request (see _sendDOMRequest), and
* - rv: the request's return value.
*
*/
_gotDOMRequestResult: function(data) {
let req = this._pendingDOMRequests[data.json.id];
delete this._pendingDOMRequests[data.json.id];
Services.DOMRequest.fireSuccess(req, data.json.rv);
},
_setVisible: function(visible) {
this._sendAsyncMsg('set-visible', {visible: visible});
},
_goBack: function() {
this._sendAsyncMsg('go-back');
},
_goForward: function() {
this._sendAsyncMsg('go-forward');
},
_fireKeyEvent: function(data) {
let evt = this._window.document.createEvent("KeyboardEvent");
evt.initKeyEvent(data.json.type, true, true, this._window,
false, false, false, false, // modifiers
data.json.keyCode,
data.json.charCode);
this._frameElement.dispatchEvent(evt);
},
};
var NSGetFactory = XPCOMUtils.generateNSGetFactory([BrowserElementParentFactory]);