| /* |
| * Copyright 2012 Research In Motion Limited. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| var utils = require('./utils'), |
| exception = require('./exception'), |
| _listeners = {}; |
| |
| function _on(eventType, listener, scope, once) { |
| if (!eventType) { |
| throw "eventType must be truthy"; |
| } |
| _listeners[eventType] = _listeners[eventType] || []; |
| _listeners[eventType].push({ |
| func: listener, |
| scope: scope, |
| once: !!once |
| }); |
| } |
| |
| function _trigger(listener, args, sync) { |
| try { |
| if (sync) { |
| listener.func.apply(listener.scope, args); |
| } |
| else { |
| setTimeout(function () { |
| listener.func.apply(listener.scope, args); |
| }, 1); |
| } |
| } |
| catch (e) { |
| exception.handle(e); |
| } |
| } |
| |
| module.exports = { |
| on: function (eventType, listener, scope) { |
| _on(eventType, listener, scope, false); |
| }, |
| |
| once: function (eventType, listener, scope) { |
| _on(eventType, listener, scope, true); |
| }, |
| |
| trigger: function (eventType, args, sync) { |
| args = args || []; |
| sync = sync || false; |
| |
| var listeners = _listeners[eventType]; |
| |
| if (listeners) { |
| listeners.forEach(function (listener) { |
| _trigger(listener, args, sync); |
| }); |
| |
| _listeners[eventType] = listeners.filter(function (listener) { |
| return !listener.once; |
| }); |
| } |
| }, |
| |
| eventHasSubscriber: function (eventType) { |
| return !!_listeners[eventType]; |
| }, |
| |
| getEventSubscribers: function (eventType) { |
| return utils.copy(_listeners[eventType]) || []; |
| }, |
| |
| clear: function (eventType) { |
| if (eventType) { |
| delete _listeners[eventType]; |
| } |
| } |
| }; |