The Tor Browser / file comparison
comparison: addon-sdk/source/lib/sdk/event/chrome.js
addon-sdk/source/lib/sdk/event/chrome.js
- branch
- TOR_BUG_9701
- changeset 15
- b8a032363ba2
equal
deleted
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| -1:000000000000 | 0:a2975512d60a |
|---|---|
| 1 /* This Source Code Form is subject to the terms of the Mozilla Public | |
| 2 * License, v. 2.0. If a copy of the MPL was not distributed with this | |
| 3 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ | |
| 4 | |
| 5 "use strict"; | |
| 6 | |
| 7 module.metadata = { | |
| 8 "stability": "unstable" | |
| 9 }; | |
| 10 | |
| 11 const { Cc, Ci, Cr } = require("chrome"); | |
| 12 const { emit, on, off } = require("./core"); | |
| 13 const { addObserver } = Cc['@mozilla.org/observer-service;1']. | |
| 14 getService(Ci.nsIObserverService); | |
| 15 | |
| 16 // Simple class that can be used to instantiate event channel that | |
| 17 // implements `nsIObserver` interface. It's will is used by `observe` | |
| 18 // function as observer + event target. It basically proxies observer | |
| 19 // notifications as to it's registered listeners. | |
| 20 function ObserverChannel() {} | |
| 21 Object.freeze(Object.defineProperties(ObserverChannel.prototype, { | |
| 22 QueryInterface: { | |
| 23 value: function(iid) { | |
| 24 if (!iid.equals(Ci.nsIObserver) && | |
| 25 !iid.equals(Ci.nsISupportsWeakReference) && | |
| 26 !iid.equals(Ci.nsISupports)) | |
| 27 throw Cr.NS_ERROR_NO_INTERFACE; | |
| 28 return this; | |
| 29 } | |
| 30 }, | |
| 31 observe: { | |
| 32 value: function(subject, topic, data) { | |
| 33 emit(this, "data", { | |
| 34 type: topic, | |
| 35 target: subject, | |
| 36 data: data | |
| 37 }); | |
| 38 } | |
| 39 } | |
| 40 })); | |
| 41 | |
| 42 function observe(topic) { | |
| 43 let observerChannel = new ObserverChannel(); | |
| 44 | |
| 45 // Note: `nsIObserverService` will not hold a weak reference to a | |
| 46 // observerChannel (since third argument is `true`). There for if it | |
| 47 // will be GC-ed with all it's event listeners once no other references | |
| 48 // will be held. | |
| 49 addObserver(observerChannel, topic, true); | |
| 50 | |
| 51 return observerChannel; | |
| 52 } | |
| 53 | |
| 54 exports.observe = observe; |
