/**
* Augments the Event Utility with support for the mouseenter and mouseleave
* events: A mouseenter event fires the first time the mouse enters an
* element; a mouseleave event first the first time the mouse leaves an
* element.
*
* @module event-mouseenter
* @title Event Utility mouseenter and mouseout Module
* @namespace YAHOO.util
* @requires event
*/
(function () {
var Event = YAHOO.util.Event,
Lang = YAHOO.lang,
addListener = Event.addListener,
removeListener = Event.removeListener,
getListeners = Event.getListeners,
delegates = [],
specialTypes = {
mouseenter: "mouseover",
mouseleave: "mouseout"
},
remove = function(el, type, fn) {
var index = Event._getCacheIndex(delegates, el, type, fn),
cacheItem,
returnVal;
if (index >= 0) {
cacheItem = delegates[index];
}
if (el && cacheItem) {
// removeListener will translate the value of type
returnVal = removeListener.call(Event, cacheItem[0], type, cacheItem[3]);
if (returnVal) {
delete delegates[index][2];
delete delegates[index][3];
delegates.splice(index, 1);
}
}
return returnVal;
};
Lang.augmentObject(Event._specialTypes, specialTypes);
Lang.augmentObject(Event, {
/**
* Creates a delegate function used to call mouseover and mouseleave
* event listeners specified via the
* <code>YAHOO.util.Event.addListener</code>
* or <code>YAHOO.util.Event.on</code> method.
*
* @method _createMouseDelegate
*
* @param {Function} fn The method (event listener) to call
* @param {Object} obj An arbitrary object that will be
* passed as a parameter to the listener
* @param {Boolean|object} overrideContext If true, the value of the
* obj parameter becomes the execution context
* of the listener. If an object, this object
* becomes the execution context.
* @return {Function} Function that will call the event listener
* specified by either the <code>YAHOO.util.Event.addListener</code>
* or <code>YAHOO.util.Event.on</code> method.
* @private
* @static
* @for Event
*/
_createMouseDelegate: function (fn, obj, overrideContext) {
return function (event, container) {
var el = this,
relatedTarget = Event.getRelatedTarget(event),
context,
args;
if (el != relatedTarget && !YAHOO.util.Dom.isAncestor(el, relatedTarget)) {
context = el;
if (overrideContext) {
if (overrideContext === true) {
context = obj;
} else {
context = overrideContext;
}
}
// The default args passed back to a mouseenter or
// mouseleave listener are: the event, and any object
// the user passed when subscribing
args = [event, obj];
// Add the element and delegation container as arguments
// when delegating mouseenter and mouseleave
if (container) {
args.splice(1, 0, el, container);
}
return fn.apply(context, args);
}
};
},
addListener: function (el, type, fn, obj, overrideContext) {
var fnDelegate,
returnVal;
if (specialTypes[type]) {
fnDelegate = Event._createMouseDelegate(fn, obj, overrideContext);
fnDelegate.mouseDelegate = true;
delegates.push([el, type, fn, fnDelegate]);
// addListener will translate the value of type
returnVal = addListener.call(Event, el, type, fnDelegate);
}
else {
returnVal = addListener.apply(Event, arguments);
}
return returnVal;
},
removeListener: function (el, type, fn) {
var returnVal;
if (specialTypes[type]) {
returnVal = remove.apply(Event, arguments);
}
else {
returnVal = removeListener.apply(Event, arguments);
}
return returnVal;
},
getListeners: function (el, type) {
// If the user specified the type as mouseover or mouseout,
// need to filter out those used by mouseenter and mouseleave.
// If the user specified the type as mouseenter or mouseleave,
// need to filter out the true mouseover and mouseout listeners.
var listeners = [],
elListeners,
bMouseOverOrOut = (type === "mouseover" || type === "mouseout"),
bMouseDelegate,
i,
l;
if (type && (bMouseOverOrOut || specialTypes[type])) {
elListeners = getListeners.call(Event, el, this._getType(type));
if (elListeners) {
for (i=elListeners.length-1; i>-1; i--) {
l = elListeners[i];
bMouseDelegate = l.fn.mouseDelegate;
if ((specialTypes[type] && bMouseDelegate) || (bMouseOverOrOut && !bMouseDelegate)) {
listeners.push(l);
}
}
}
}
else {
listeners = getListeners.apply(Event, arguments);
}
return (listeners && listeners.length) ? listeners : null;
}
}, true);
Event.on = Event.addListener;
}());