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Diffstat (limited to 'tools/addon-sdk-1.7/packages/api-utils/lib/observer-service.js')
| -rw-r--r-- | tools/addon-sdk-1.7/packages/api-utils/lib/observer-service.js | 175 |
1 files changed, 0 insertions, 175 deletions
diff --git a/tools/addon-sdk-1.7/packages/api-utils/lib/observer-service.js b/tools/addon-sdk-1.7/packages/api-utils/lib/observer-service.js deleted file mode 100644 index 04222c7..0000000 --- a/tools/addon-sdk-1.7/packages/api-utils/lib/observer-service.js +++ /dev/null @@ -1,175 +0,0 @@ -/* 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"; - -const { Cc, Ci } = require("chrome"); -const { Unknown } = require("./xpcom"); -const { when: unload } = require("./unload"); -const memory = require("./memory"); - - -/** - * A service for adding, removing and notifying observers of notifications. - * Wraps the nsIObserverService interface. - * - * @version 0.2 - */ - -var service = Cc["@mozilla.org/observer-service;1"]. - getService(Ci.nsIObserverService); - -/** - * A cache of observers that have been added. - * - * We use this to remove observers when a caller calls |Observers.remove|. - */ -var cache = []; - -/** - * Topics specifically available to Jetpack-generated extensions. - * - * Using these predefined consts instead of the platform strings is good: - * - allows us to scope topics specifically for Jetpacks - * - addons aren't dependent on strings nor behavior of core platform topics - * - the core platform topics are not clearly named - * - */ -exports.topics = { - /** - * A topic indicating that the application is in a state usable - * by add-ons. - */ - get APPLICATION_READY() packaging.jetpackID + "_APPLICATION_READY" -}; - -/** - * Register the given callback as an observer of the given topic. - * - * @param topic {String} - * the topic to observe - * - * @param callback {Object} - * the callback; an Object that implements nsIObserver or a Function - * that gets called when the notification occurs - * - * @param target {Object} [optional] - * the object to use as |this| when calling a Function callback - * - * @returns the observer - */ -var add = exports.add = function add(topic, callback, target) { - var observer = Observer.new(topic, callback, target); - service.addObserver(observer, topic, true); - cache.push(observer); - - return observer; -}; - -/** - * Unregister the given callback as an observer of the given topic. - * - * @param topic {String} - * the topic being observed - * - * @param callback {Object} - * the callback doing the observing - * - * @param target {Object} [optional] - * the object being used as |this| when calling a Function callback - */ -var remove = exports.remove = function remove(topic, callback, target) { - // This seems fairly inefficient, but I'm not sure how much better - // we can make it. We could index by topic, but we can't index by callback - // or target, as far as I know, since the keys to JavaScript hashes - // (a.k.a. objects) can apparently only be primitive values. - let observers = cache.filter(function(v) { - return (v.topic == topic && - v.callback == callback && - v.target == target); - }); - - if (observers.length) { - service.removeObserver(observers[0], topic); - cache.splice(cache.indexOf(observers[0]), 1); - } -}; - -/** - * Notify observers about something. - * - * @param topic {String} - * the topic to notify observers about - * - * @param subject {Object} [optional] - * some information about the topic; can be any JS object or primitive - * - * @param data {String} [optional] [deprecated] - * some more information about the topic; deprecated as the subject - * is sufficient to pass all needed information to the JS observers - * that this module targets; if you have multiple values to pass to - * the observer, wrap them in an object and pass them via the subject - * parameter (i.e.: { foo: 1, bar: "some string", baz: myObject }) - */ -var notify = exports.notify = function notify(topic, subject, data) { - subject = (typeof subject == "undefined") ? null : Subject.new(subject); - data = (typeof data == "undefined") ? null : data; - service.notifyObservers(subject, topic, data); -}; - -const Observer = Unknown.extend({ - initialize: function initialize(topic, callback, target) { - memory.track(this); - this.topic = topic; - this.callback = callback; - this.target = target; - }, - interfaces: [ 'nsIObserver', 'nsISupportsWeakReference' ], - observe: function(subject, topic, data) { - // Extract the wrapped object for subjects that are one of our - // wrappers around a JS object. This way we support both wrapped - // subjects created using this module and those that are real - // XPCOM components. - if (subject && typeof subject == "object" && - ("wrappedJSObject" in subject) && - ("observersModuleSubjectWrapper" in subject.wrappedJSObject)) - subject = subject.wrappedJSObject.object; - - try { - if (typeof this.callback == "function") { - if (this.target) - this.callback.call(this.target, subject, data); - else - this.callback(subject, data); - } else // typeof this.callback == "object" (nsIObserver) - this.callback.observe(subject, topic, data); - } catch (e) { - console.exception(e); - } - } -}); - -const Subject = Unknown.extend({ - initialize: function initialize(object) { - // Double-wrap the object and set a property identifying the - // wrappedJSObject as one of our wrappers to distinguish between - // subjects that are one of our wrappers (which we should unwrap - // when notifying our observers) and those that are real JS XPCOM - // components (which we should pass through unaltered). - this.wrappedJSObject = { - observersModuleSubjectWrapper: true, - object: object - }; - }, - getHelperForLanguage: function() {}, - getInterfaces: function() {} -}); - -unload(function() { - // Make a copy of cache first, since cache will be changing as we - // iterate through it. - cache.slice().forEach(function({ topic, callback, target }) { - remove(topic, callback, target); - }); -}) |