/** * Adds event facades, preventable default behavior, and bubbling. * events. * @module event-custom * @submodule event-custom-complex */ var FACADE, FACADE_KEYS, YObject = Y.Object, key, EMPTY = {}, CEProto = Y.CustomEvent.prototype, ETProto = Y.EventTarget.prototype, mixFacadeProps = function(facade, payload) { var p; for (p in payload) { if (!(FACADE_KEYS.hasOwnProperty(p))) { facade[p] = payload[p]; } } }; /** * Wraps and protects a custom event for use when emitFacade is set to true. * Requires the event-custom-complex module * @class EventFacade * @param e {Event} the custom event * @param currentTarget {HTMLElement} the element the listener was attached to */ Y.EventFacade = function(e, currentTarget) { if (!e) { e = EMPTY; } this._event = e; /** * The arguments passed to fire * @property details * @type Array */ this.details = e.details; /** * The event type, this can be overridden by the fire() payload * @property type * @type string */ this.type = e.type; /** * The real event type * @property _type * @type string * @private */ this._type = e.type; ////////////////////////////////////////////////////// /** * Node reference for the targeted eventtarget * @property target * @type Node */ this.target = e.target; /** * Node reference for the element that the listener was attached to. * @property currentTarget * @type Node */ this.currentTarget = currentTarget; /** * Node reference to the relatedTarget * @property relatedTarget * @type Node */ this.relatedTarget = e.relatedTarget; }; Y.mix(Y.EventFacade.prototype, { /** * Stops the propagation to the next bubble target * @method stopPropagation */ stopPropagation: function() { this._event.stopPropagation(); this.stopped = 1; }, /** * Stops the propagation to the next bubble target and * prevents any additional listeners from being exectued * on the current target. * @method stopImmediatePropagation */ stopImmediatePropagation: function() { this._event.stopImmediatePropagation(); this.stopped = 2; }, /** * Prevents the event's default behavior * @method preventDefault */ preventDefault: function() { this._event.preventDefault(); this.prevented = 1; }, /** * Stops the event propagation and prevents the default * event behavior. * @method halt * @param immediate {boolean} if true additional listeners * on the current target will not be executed */ halt: function(immediate) { this._event.halt(immediate); this.prevented = 1; this.stopped = (immediate) ? 2 : 1; } }); CEProto.fireComplex = function(args) { var es, ef, q, queue, ce, ret = true, events, subs, ons, afters, afterQueue, postponed, prevented, preventedFn, defaultFn, self = this, host = self.host || self, next, oldbubble, stack = self.stack, yuievt = host._yuievt, hasPotentialSubscribers; if (stack) { // queue this event if the current item in the queue bubbles if (self.queuable && self.type !== stack.next.type) { self.log('queue ' + self.type); if (!stack.queue) { stack.queue = []; } stack.queue.push([self, args]); return true; } } hasPotentialSubscribers = self.hasSubs() || yuievt.hasTargets || self.broadcast; self.target = self.target || host; self.currentTarget = host; self.details = args.concat(); if (hasPotentialSubscribers) { es = stack || { id: self.id, // id of the first event in the stack next: self, silent: self.silent, stopped: 0, prevented: 0, bubbling: null, type: self.type, // defaultFnQueue: new Y.Queue(), defaultTargetOnly: self.defaultTargetOnly }; subs = self.getSubs(); ons = subs[0]; afters = subs[1]; self.stopped = (self.type !== es.type) ? 0 : es.stopped; self.prevented = (self.type !== es.type) ? 0 : es.prevented; if (self.stoppedFn) { // PERF TODO: Can we replace with callback, like preventedFn. Look into history events = new Y.EventTarget({ fireOnce: true, context: host }); self.events = events; events.on('stopped', self.stoppedFn); } // self.log("Firing " + self + ", " + "args: " + args); self.log("Firing " + self.type); self._facade = null; // kill facade to eliminate stale properties ef = self._createFacade(args); if (ons) { self._procSubs(ons, args, ef); } // bubble if this is hosted in an event target and propagation has not been stopped if (self.bubbles && host.bubble && !self.stopped) { oldbubble = es.bubbling; es.bubbling = self.type; if (es.type !== self.type) { es.stopped = 0; es.prevented = 0; } ret = host.bubble(self, args, null, es); self.stopped = Math.max(self.stopped, es.stopped); self.prevented = Math.max(self.prevented, es.prevented); es.bubbling = oldbubble; } prevented = self.prevented; if (prevented) { preventedFn = self.preventedFn; if (preventedFn) { preventedFn.apply(host, args); } } else { defaultFn = self.defaultFn; if (defaultFn && ((!self.defaultTargetOnly && !es.defaultTargetOnly) || host === ef.target)) { defaultFn.apply(host, args); } } // broadcast listeners are fired as discreet events on the // YUI instance and potentially the YUI global. if (self.broadcast) { self._broadcast(args); } if (afters && !self.prevented && self.stopped < 2) { // Queue the after afterQueue = es.afterQueue; if (es.id === self.id || self.type !== yuievt.bubbling) { self._procSubs(afters, args, ef); if (afterQueue) { while ((next = afterQueue.last())) { next(); } } } else { postponed = afters; if (es.execDefaultCnt) { postponed = Y.merge(postponed); Y.each(postponed, function(s) { s.postponed = true; }); } if (!afterQueue) { es.afterQueue = new Y.Queue(); } es.afterQueue.add(function() { self._procSubs(postponed, args, ef); }); } } self.target = null; if (es.id === self.id) { queue = es.queue; if (queue) { while (queue.length) { q = queue.pop(); ce = q[0]; // set up stack to allow the next item to be processed es.next = ce; ce._fire(q[1]); } } self.stack = null; } ret = !(self.stopped); if (self.type !== yuievt.bubbling) { es.stopped = 0; es.prevented = 0; self.stopped = 0; self.prevented = 0; } } else { defaultFn = self.defaultFn; if(defaultFn) { ef = self._createFacade(args); if ((!self.defaultTargetOnly) || (host === ef.target)) { defaultFn.apply(host, args); } } } // Kill the cached facade to free up memory. // Otherwise we have the facade from the last fire, sitting around forever. self._facade = null; return ret; }; /** * @method _hasPotentialSubscribers * @for CustomEvent * @private * @return {boolean} Whether the event has potential subscribers or not */ CEProto._hasPotentialSubscribers = function() { return this.hasSubs() || this.host._yuievt.hasTargets || this.broadcast; }; /** * Internal utility method to create a new facade instance and * insert it into the fire argument list, accounting for any payload * merging which needs to happen. * * This used to be called `_getFacade`, but the name seemed inappropriate * when it was used without a need for the return value. * * @method _createFacade * @private * @param fireArgs {Array} The arguments passed to "fire", which need to be * shifted (and potentially merged) when the facade is added. * @return {EventFacade} The event facade created. */ // TODO: Remove (private) _getFacade alias, once synthetic.js is updated. CEProto._createFacade = CEProto._getFacade = function(fireArgs) { var userArgs = this.details, firstArg = userArgs && userArgs[0], firstArgIsObj = (firstArg && (typeof firstArg === "object")), ef = this._facade; if (!ef) { ef = new Y.EventFacade(this, this.currentTarget); } if (firstArgIsObj) { // protect the event facade properties mixFacadeProps(ef, firstArg); // Allow the event type to be faked http://yuilibrary.com/projects/yui3/ticket/2528376 if (firstArg.type) { ef.type = firstArg.type; } if (fireArgs) { fireArgs[0] = ef; } } else { if (fireArgs) { fireArgs.unshift(ef); } } // update the details field with the arguments ef.details = this.details; // use the original target when the event bubbled to this target ef.target = this.originalTarget || this.target; ef.currentTarget = this.currentTarget; ef.stopped = 0; ef.prevented = 0; this._facade = ef; return this._facade; }; /** * Utility method to manipulate the args array passed in, to add the event facade, * if it's not already the first arg. * * @method _addFacadeToArgs * @private * @param {Array} The arguments to manipulate */ CEProto._addFacadeToArgs = function(args) { var e = args[0]; // Trying not to use instanceof, just to avoid potential cross Y edge case issues. if (!(e && e.halt && e.stopImmediatePropagation && e.stopPropagation && e._event)) { this._createFacade(args); } }; /** * Stop propagation to bubble targets * @for CustomEvent * @method stopPropagation */ CEProto.stopPropagation = function() { this.stopped = 1; if (this.stack) { this.stack.stopped = 1; } if (this.events) { this.events.fire('stopped', this); } }; /** * Stops propagation to bubble targets, and prevents any remaining * subscribers on the current target from executing. * @method stopImmediatePropagation */ CEProto.stopImmediatePropagation = function() { this.stopped = 2; if (this.stack) { this.stack.stopped = 2; } if (this.events) { this.events.fire('stopped', this); } }; /** * Prevents the execution of this event's defaultFn * @method preventDefault */ CEProto.preventDefault = function() { if (this.preventable) { this.prevented = 1; if (this.stack) { this.stack.prevented = 1; } } }; /** * Stops the event propagation and prevents the default * event behavior. * @method halt * @param immediate {boolean} if true additional listeners * on the current target will not be executed */ CEProto.halt = function(immediate) { if (immediate) { this.stopImmediatePropagation(); } else { this.stopPropagation(); } this.preventDefault(); }; /** * Registers another EventTarget as a bubble target. Bubble order * is determined by the order registered. Multiple targets can * be specified. * * Events can only bubble if emitFacade is true. * * Included in the event-custom-complex submodule. * * @method addTarget * @chainable * @param o {EventTarget} the target to add * @for EventTarget */ ETProto.addTarget = function(o) { var etState = this._yuievt; if (!etState.targets) { etState.targets = {}; } etState.targets[Y.stamp(o)] = o; etState.hasTargets = true; return this; }; /** * Returns an array of bubble targets for this object. * @method getTargets * @return EventTarget[] */ ETProto.getTargets = function() { var targets = this._yuievt.targets; return targets ? YObject.values(targets) : []; }; /** * Removes a bubble target * @method removeTarget * @chainable * @param o {EventTarget} the target to remove * @for EventTarget */ ETProto.removeTarget = function(o) { var targets = this._yuievt.targets; if (targets) { delete targets[Y.stamp(o, true)]; if (YObject.size(targets) === 0) { this._yuievt.hasTargets = false; } } return this; }; /** * Propagate an event. Requires the event-custom-complex module. * @method bubble * @param evt {CustomEvent} the custom event to propagate * @return {boolean} the aggregated return value from Event.Custom.fire * @for EventTarget */ ETProto.bubble = function(evt, args, target, es) { var targs = this._yuievt.targets, ret = true, t, ce, i, bc, ce2, type = evt && evt.type, originalTarget = target || (evt && evt.target) || this, oldbubble; if (!evt || ((!evt.stopped) && targs)) { for (i in targs) { if (targs.hasOwnProperty(i)) { t = targs[i]; ce = t._yuievt.events[type]; if (t._hasSiblings) { ce2 = t.getSibling(type, ce); } if (ce2 && !ce) { ce = t.publish(type); } oldbubble = t._yuievt.bubbling; t._yuievt.bubbling = type; // if this event was not published on the bubble target, // continue propagating the event. if (!ce) { if (t._yuievt.hasTargets) { t.bubble(evt, args, originalTarget, es); } } else { if (ce2) { ce.sibling = ce2; } // set the original target to that the target payload on the facade is correct. ce.target = originalTarget; ce.originalTarget = originalTarget; ce.currentTarget = t; bc = ce.broadcast; ce.broadcast = false; // default publish may not have emitFacade true -- that // shouldn't be what the implementer meant to do ce.emitFacade = true; ce.stack = es; // TODO: See what's getting in the way of changing this to use // the more performant ce._fire(args || evt.details || []). // Something in Widget Parent/Child tests is not happy if we // change it - maybe evt.details related? ret = ret && ce.fire.apply(ce, args || evt.details || []); ce.broadcast = bc; ce.originalTarget = null; // stopPropagation() was called if (ce.stopped) { break; } } t._yuievt.bubbling = oldbubble; } } } return ret; }; /** * @method _hasPotentialSubscribers * @for EventTarget * @private * @param {String} fullType The fully prefixed type name * @return {boolean} Whether the event has potential subscribers or not */ ETProto._hasPotentialSubscribers = function(fullType) { var etState = this._yuievt, e = etState.events[fullType]; if (e) { return e.hasSubs() || etState.hasTargets || e.broadcast; } else { return false; } }; FACADE = new Y.EventFacade(); FACADE_KEYS = {}; // Flatten whitelist for (key in FACADE) { FACADE_KEYS[key] = true; }