Files
tubestation/addon-sdk/source/lib/sdk/keyboard/observer.js
2013-08-20 18:24:12 -07:00

58 lines
2.0 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";
module.metadata = {
"stability": "unstable"
};
const { Trait } = require("../deprecated/light-traits");
const { EventEmitterTrait: EventEmitter } = require("../deprecated/events");
const { DOMEventAssembler } = require("../deprecated/events/assembler");
const { browserWindowIterator } = require('../deprecated/window-utils');
const { isBrowser } = require('../window/utils');
const { observer: windowObserver } = require("../windows/observer");
// Event emitter objects used to register listeners and emit events on them
// when they occur.
const observer = Trait.compose(DOMEventAssembler, EventEmitter).create({
/**
* Method is implemented by `EventEmitter` and is used just for emitting
* events on registered listeners.
*/
_emit: Trait.required,
/**
* Events that are supported and emitted by the module.
*/
supportedEventsTypes: [ "keydown", "keyup", "keypress" ],
/**
* Function handles all the supported events on all the windows that are
* observed. Method is used to proxy events to the listeners registered on
* this event emitter.
* @param {Event} event
* Keyboard event being emitted.
*/
handleEvent: function handleEvent(event) {
this._emit(event.type, event, event.target.ownerDocument.defaultView);
}
});
// Adding each opened window to a list of observed windows.
windowObserver.on("open", function onOpen(window) {
if (isBrowser(window))
observer.observe(window);
});
// Removing each closed window form the list of observed windows.
windowObserver.on("close", function onClose(window) {
if (isBrowser(window))
observer.ignore(window);
});
// Making observer aware of already opened windows.
for each (let window in browserWindowIterator())
observer.observe(window);
exports.observer = observer;