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/* 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
"use strict";
/**
* Handles adding an observer for the creation of content document globals,
* event sent immediately after a web content document window has been set up,
* but before any script code has been executed.
*/
function ContentObserver(targetActor) {
this._contentWindow = targetActor.window;
this._onContentGlobalCreated = this._onContentGlobalCreated.bind(this);
this._onInnerWindowDestroyed = this._onInnerWindowDestroyed.bind(this);
this.startListening();
}
module.exports.ContentObserver = ContentObserver;
ContentObserver.prototype = {
/**
* Starts listening for the required observer messages.
*/
startListening() {
Services.obs.addObserver(
this._onContentGlobalCreated,
"content-document-global-created"
);
Services.obs.addObserver(
this._onInnerWindowDestroyed,
"inner-window-destroyed"
);
},
/**
* Stops listening for the required observer messages.
*/
stopListening() {
Services.obs.removeObserver(
this._onContentGlobalCreated,
"content-document-global-created"
);
Services.obs.removeObserver(
this._onInnerWindowDestroyed,
"inner-window-destroyed"
);
},
/**
* Fired immediately after a web content document window has been set up.
*/
_onContentGlobalCreated(subject) {
if (subject == this._contentWindow) {
EventEmitter.emit(this, "global-created", subject);
}
},
/**
* Fired when an inner window is removed from the backward/forward cache.
*/
_onInnerWindowDestroyed(subject) {
const id = subject.QueryInterface(Ci.nsISupportsPRUint64).data;
EventEmitter.emit(this, "global-destroyed", id);
},
};
// Utility functions.
ContentObserver.GetInnerWindowID = function (window) {
return window.windowGlobalChild.innerWindowId;
};