Scholar.Notifier = new function(){ var _observers = new Array(); var _disabled = false; _observers['columnTree'] = new Scholar.Hash(); _observers['itemTree'] = new Scholar.Hash(); this.registerColumnTree = registerColumnTree; this.registerItemTree = registerItemTree; this.unregisterColumnTree = unregisterColumnTree; this.unregisterItemTree = unregisterItemTree; this.trigger = trigger; this.disable = disable; this.enable = enable; this.isEnabled = isEnabled; function registerColumnTree(ref){ return _register('columnTree', ref); } function registerItemTree(ref){ return _register('itemTree', ref); } function unregisterColumnTree(hash){ _unregister('columnTree', hash); } function unregisterItemTree(hash){ _unregister('itemTree', hash); } /** * event - 'add', 'remove', 'modify' * type - 'collection', 'search', 'item' * ids - single id or array of ids **/ function trigger(event, type, ids){ if (_disabled){ return false; } switch (type){ case 'item': var treeType = 'itemTree'; break; case 'collection': case 'search': var treeType = 'columnTree'; break; default: throw('Invalid type ' + type + ' in Notifier.trigger()'); } Scholar.debug("Notifier.trigger('" + event + "', '" + type + "', " + (typeof ids=='object' ? '[' + ids.join() + ']' : ids) + ") called " + "[column trees: " + _observers['columnTree'].length + ", item trees: " + _observers['itemTree'].length + "]"); for (i in _observers[treeType].items){ Scholar.debug("Calling notify() on " + treeType + " with hash '" + i + "'", 4); _observers[treeType].get(i).notify(event, type, ids); } return true; } function disable(){ Scholar.debug('Disabling Notifier notifications'); _disabled = true; } function enable(){ Scholar.debug('Enabling Notifier notifications'); _disabled = false; } function isEnabled(){ return !_disabled; } function _register(type, ref){ var len = 2; var tries = 10; do { // Increase the hash length if we can't find a unique key if (!tries){ len++; tries = 10; } var hash = Scholar.randomString(len); tries--; } while (_observers[type].get(hash)); Scholar.debug('Registering ' + type + " in notifier with hash '" + hash + "'", 4); _observers[type].set(hash, ref); return hash; } function _unregister(type, hash){ Scholar.debug("Unregistering " + type + " in notifier with hash '" + hash + "'", 4); _observers[type].remove(hash); } }