comt: comparison src/cm/media/js/lib/yui/yui_3.0.0b1/build/node-focusmanager/node-focusmanager-debug.js

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src/cm/media/js/lib/yui/yui_3.0.0b1/build/node-focusmanager/node-focusmanager-debug.js

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+:40c8f766c9b8
+/*
+Copyright (c) 2009, Yahoo! Inc. All rights reserved.
+Code licensed under the BSD License:
+http://developer.yahoo.net/yui/license.txt
+version: 3.0.0b1
+build: 1163
+*/
+YUI.add('node-focusmanager', function(Y) {
+/**
+* <p>The Focus Manager Node Plugin makes it easy to manage focus among
+* a Node's descendants.  Primarily intended to help with widget development,
+* the Focus Manager Node Plugin can be used to improve the keyboard
+* accessibility of widgets.</p>
+*
+* <p>
+* When designing widgets that manage a set of descendant controls (i.e. buttons
+* in a toolbar, tabs in a tablist, menuitems in a menu, etc.) it is important to
+* limit the number of descendants in the browser's default tab flow.  The fewer
+* number of descendants in the default tab flow, the easier it is for keyboard
+* users to navigate between widgets by pressing the tab key.  When a widget has
+* focus it should provide a set of shortcut keys (typically the arrow keys)
+* to move focus among its descendants.
+* </p>
+*
+* <p>
+* To this end, the Focus Manager Node Plugin makes it easy to define a Node's
+* focusable descendants, define which descendant should be in the default tab
+* flow, and define the keys that move focus among each descendant.
+* Additionally, as the CSS
+* <a href="http://www.w3.org/TR/CSS21/selector.html#x38"><code>:focus</code></a>
+* pseudo class is not supported on all elements in all
+* <a href="http://developer.yahoo.com/yui/articles/gbs/">A-Grade browsers</a>,
+* the Focus Manager Node Plugin provides an easy, cross-browser means of
+* styling focus.
+* </p>
+*
+* @module node-focusmanager
+*/
+	//	Frequently used strings
+var ACTIVE_DESCENDANT = "activeDescendant",
+	ID = "id",
+	DISABLED = "disabled",
+	TAB_INDEX = "tabIndex",
+	FOCUSED = "focused",
+	FOCUS_CLASS = "focusClass",
+	CIRCULAR = "circular",
+	UI = "UI",
+	KEY = "key",
+	ACTIVE_DESCENDANT_CHANGE = ACTIVE_DESCENDANT + "Change",
+	HOST = "host",
+	//	Collection of keys that, when pressed, cause the browser viewport
+	//	to scroll.
+	scrollKeys = {
+		37: true,
+		38: true,
+		39: true,
+		40: true
+	},
+	clickableElements = {
+		"a": true,
+		"button": true,
+		"input": true,
+		"object": true
+	},
+	//	Library shortcuts
+	Lang = Y.Lang,
+	UA = Y.UA,
+	/**
+	* The NodeFocusManager class is a plugin for a Node instance.  The class is used
+	* via the <a href="Node.html#method_plug"><code>plug</code></a> method of Node
+	* and should not be instantiated directly.
+	* @namespace plugin
+	* @class NodeFocusManager
+	*/
+	NodeFocusManager = function () {
+		NodeFocusManager.superclass.constructor.apply(this, arguments);
+	};
+NodeFocusManager.ATTRS = {
+	/**
+	* Boolean indicating that one of the descendants is focused.
+	*
+	* @attribute focused
+	* @readOnly
+	* @default false
+	* @type boolean
+	*/
+	focused: {
+		value: false,
+		readOnly: true
+	},
+	/**
+	* String representing the CSS selector used to define the descendant Nodes
+	* whose focus should be managed.
+	*
+	* @attribute descendants
+	* @type Y.NodeList
+	*/
+	descendants: {
+		getter: function (value) {
+			return this.get(HOST).queryAll(value);
+		}
+	},
+	/**
+	* <p>Node, or index of the Node, representing the descendant that is either
+	* focused or is focusable (<code>tabIndex</code> attribute is set to 0).
+	* The value cannot represent a disabled descendant Node.  Use a value of -1
+	* to remove all descendant Nodes from the default tab flow.
+	* If no value is specified, the active descendant will be inferred using
+	* the following criteria:</p>
+	* <ol>
+	* <li>Examining the <code>tabIndex</code> attribute of each descendant and
+	* using the first descendant whose <code>tabIndex</code> attribute is set
+	* to 0</li>
+	* <li>If no default can be inferred then the value is set to either 0 or
+	* the index of the first enabled descendant.</li>
+	* </ol>
+	*
+	* @attribute activeDescendant
+	* @type Number
+	*/
+	activeDescendant: {
+		setter: function (value) {
+			var isNumber = Lang.isNumber,
+				INVALID_VALUE = Y.Attribute.INVALID_VALUE,
+				descendantsMap = this._descendantsMap,
+				descendants = this._descendants,
+				nodeIndex,
+				returnValue,
+				oNode;
+			if (isNumber(value)) {
+				nodeIndex = value;
+				returnValue = nodeIndex;
+			}
+			else if ((value instanceof Y.Node) && descendantsMap) {
+				nodeIndex = descendantsMap[value.get(ID)];
+				if (isNumber(nodeIndex)) {
+					returnValue = nodeIndex;
+				}
+				else {
+					//	The user passed a reference to a Node that wasn't one
+					//	of the descendants.
+					returnValue = INVALID_VALUE;
+				}
+			}
+			else {
+				returnValue = INVALID_VALUE;
+			}
+			if (descendants) {
+				oNode = descendants.item(nodeIndex);
+				if (oNode && oNode.get("disabled")) {
+					//	Setting the "activeDescendant" attribute to the index
+					//	of a disabled descendant is invalid.
+					returnValue = INVALID_VALUE;
+				}
+			}
+			return returnValue;
+		}
+	},
+	/**
+	* Object literal representing the keys to be used to navigate between the
+	* next/previous descendant.  The format for the attribute's value is
+	* <code>{ next: "down:40", previous: "down:38" }</code>.  The value for the
+	* "next" and "previous" properties are used to attach
+	* <a href="event/#keylistener"><code>key</code></a> event listeners. See
+	* the <a href="event/#keylistener">Using the key Event</a> section of
+	* the Event documentation for more information on "key" event listeners.
+	*
+	* @attribute keys
+	* @type Object
+	*/
+	keys: {
+		value: {
+			next: null,
+			previous: null
+		}
+	},
+	/**
+	* String representing the name of class applied to the focused active
+	* descendant Node.  Can also be an object literal used to define both the
+	* class name, and the Node to which the class should be applied.  If using
+	* an object literal, the format is:
+	* <code>{ className: "focus", fn: myFunction }</code>.  The function
+	* referenced by the <code>fn</code> property in the object literal will be
+	* passed a reference to the currently focused active descendant Node.
+	*
+	* @attribute focusClass
+	* @type String|Object
+	*/
+	focusClass: { },
+	/**
+	* Boolean indicating if focus should be set to the first/last descendant
+	* when the end or beginning of the descendants has been reached.
+	*
+	* @attribute circular
+	* @type Boolean
+	*/
+	circular: {
+		value: true
+	}
+};
+Y.extend(NodeFocusManager, Y.Plugin.Base, {
+	//	Protected properties
+	//	Boolean indicating if the NodeFocusManager is active.
+	_stopped: true,
+	//	NodeList representing the descendants selected via the
+	//	"descendants" attribute.
+	_descendants: null,
+	//	Object literal mapping the IDs of each descendant to its index in the
+	//	"_descendants" NodeList.
+	_descendantsMap: null,
+	//	Reference to the Node instance to which the focused class (defined
+	//	by the "focusClass" attribute) is currently applied.
+	_focusedNode: null,
+	//	Number representing the index of the last descendant Node.
+	_lastNodeIndex: 0,
+	//	Array of handles for event handlers used for a NodeFocusManager instance.
+	_eventHandlers: null,
+	//	Protected methods
+	/**
+	* @method _initDescendants
+	* @description Sets the <code>tabIndex</code> attribute of all of the
+	* descendants to -1, except the active descendant, whose
+	* <code>tabIndex</code> attribute is set to 0.
+	* @protected
+	*/
+	_initDescendants: function () {
+		var descendants = this.get("descendants"),
+			descendantsMap = {},
+			nFirstEnabled = -1,
+			nDescendants,
+			nActiveDescendant = this.get(ACTIVE_DESCENDANT),
+			oNode,
+			sID,
+			i = 0;
+		if (Lang.isUndefined(nActiveDescendant)) {
+			nActiveDescendant = -1;
+		}
+		if (descendants) {
+			nDescendants = descendants.size();
+			if (nDescendants > 1) {
+				for (i = 0; i < nDescendants; i++) {
+					oNode = descendants.item(i);
+					if (nFirstEnabled === -1 && !oNode.get(DISABLED)) {
+						nFirstEnabled = i;
+					}
+					//	If the user didn't specify a value for the
+					//	"activeDescendant" attribute try to infer it from
+					//	the markup.
+					if (nActiveDescendant < 0 &&
+							oNode.getAttribute(TAB_INDEX) === "0") {
+						nActiveDescendant = i;
+					}
+					oNode.set(TAB_INDEX, -1);
+					sID = oNode.get(ID);
+					if (!sID) {
+						sID = Y.guid();
+						oNode.set(ID, sID);
+					}
+					descendantsMap[sID] = i;
+				}
+				//	If the user didn't specify a value for the
+				//	"activeDescendant" attribute and no default value could be
+				//	determined from the markup, then default to 0.
+				if (nActiveDescendant < 0) {
+					nActiveDescendant = 0;
+				}
+				oNode = descendants.item(nActiveDescendant);
+				//	Check to make sure the active descendant isn't disabled,
+				//	and fall back to the first enabled descendant if it is.
+				if (!oNode || oNode.get(DISABLED)) {
+					oNode = descendants.item(nFirstEnabled);
+					nActiveDescendant = nFirstEnabled;
+				}
+				this._lastNodeIndex = nDescendants - 1;
+				this._descendants = descendants;
+				this._descendantsMap = descendantsMap;
+				this.set(ACTIVE_DESCENDANT, nActiveDescendant);
+				//	Need to set the "tabIndex" attribute here, since the
+				//	"activeDescendantChange" event handler used to manage
+				//	the setting of the "tabIndex" attribute isn't wired up yet.
+				oNode.set(TAB_INDEX, 0);
+			}
+		}
+	},
+	/**
+	* @method _isDescendant
+	* @description Determines if the specified Node instance is a descendant
+	* managed by the Focus Manager.
+	* @param node {Node} Node instance to be checked.
+	* @return {Boolean} Boolean indicating if the specified Node instance is a
+	* descendant managed by the Focus Manager.
+	* @protected
+	*/
+	_isDescendant: function (node) {
+		return (node.get(ID) in this._descendantsMap);
+	},
+	/**
+	* @method _removeFocusClass
+	* @description Removes the class name representing focus (as specified by
+	* the "focusClass" attribute) from the Node instance to which it is
+	* currently applied.
+	* @protected
+	*/
+	_removeFocusClass: function () {
+		var oFocusedNode = this._focusedNode,
+			focusClass = this.get(FOCUS_CLASS),
+			sClassName;
+		if (focusClass) {
+			sClassName = Lang.isString(focusClass) ?
+				focusClass : focusClass.className;
+		}
+		if (oFocusedNode && sClassName) {
+			oFocusedNode.removeClass(sClassName);
+		}
+	},
+	/**
+	* @method _detachKeyHandler
+	* @description Detaches the "key" event handlers used to support the "keys"
+	* attribute.
+	* @protected
+	*/
+	_detachKeyHandler: function () {
+		var prevKeyHandler = this._prevKeyHandler,
+			nextKeyHandler = this._nextKeyHandler;
+		if (prevKeyHandler) {
+			prevKeyHandler.detach();
+		}
+		if (nextKeyHandler) {
+			nextKeyHandler.detach();
+		}
+	},
+	/**
+	* @method _preventScroll
+	* @description Prevents the viewport from scolling when the user presses
+	* the up, down, left, or right key.
+	* @protected
+	*/
+	_preventScroll: function (event) {
+		if (scrollKeys[event.keyCode]) {
+			event.preventDefault();
+		}
+	},
+	/**
+	* @method _preventScroll
+	* @description Fires the click event if the enter key is pressed while
+	* focused on an HTML element that is not natively clickable.
+	* @protected
+	*/
+	_fireClick: function (event) {
+		var oTarget = event.target,
+			sNodeName = oTarget.get("nodeName").toLowerCase();
+		if (event.keyCode === 13 && (!clickableElements[sNodeName] ||
+				(sNodeName === "a" && !oTarget.getAttribute("href")))) {
+			Y.log(("Firing click event for node:" + oTarget.get("id")), "info", "nodeFocusManager");
+			oTarget.simulate("click");
+		}
+	},
+	/**
+	* @method _attachKeyHandler
+	* @description Attaches the "key" event handlers used to support the "keys"
+	* attribute.
+	* @protected
+	*/
+	_attachKeyHandler: function () {
+		this._detachKeyHandler();
+		var sNextKey = this.get("keys.next"),
+			sPrevKey = this.get("keys.previous"),
+			oNode = this.get(HOST),
+			aHandlers = this._eventHandlers;
+		if (sPrevKey) {
+			this._prevKeyHandler =
+				Y.on(KEY, Y.bind(this._focusPrevious, this), oNode, sPrevKey);
+		}
+		if (sNextKey) {
+			this._nextKeyHandler =
+				Y.on(KEY, Y.bind(this._focusNext, this), oNode, sNextKey);
+		}
+		//	In Opera it is necessary to call the "preventDefault" method in
+		//	response to the user pressing the arrow keys in order to prevent
+		//	the viewport from scrolling when the user is moving focus among
+		//	the focusable descendants.
+		if (UA.opera) {
+			aHandlers.push(oNode.on("keypress", this._preventScroll, this));
+		}
+		//	For all browsers except Opera: HTML elements that are not natively
+		//	focusable but made focusable via the tabIndex attribute don't
+		//	fire a click event when the user presses the enter key.  It is
+		//	possible to work around this problem by simplying dispatching a
+		//	click event in response to the user pressing the enter key.
+		if (!UA.opera) {
+			aHandlers.push(oNode.on("keypress", this._fireClick, this));
+		}
+	},
+	/**
+	* @method _detachEventHandlers
+	* @description Detaches all event handlers used by the Focus Manager.
+	* @protected
+	*/
+	_detachEventHandlers: function () {
+		this._detachKeyHandler();
+		var aHandlers = this._eventHandlers;
+		if (aHandlers) {
+			Y.Array.each(aHandlers, function (handle) {
+				handle.detach();
+			});
+			this._eventHandlers = null;
+		}
+	},
+	/**
+	* @method _detachEventHandlers
+	* @description Attaches all event handlers used by the Focus Manager.
+	* @protected
+	*/
+	_attachEventHandlers: function () {
+		var descendants = this._descendants,
+			aHandlers,
+			oDocument,
+			handle;
+		if (descendants && descendants.size() > 1) {
+			aHandlers = this._eventHandlers || [];
+			oDocument = this.get(HOST).get("ownerDocument");
+			if (aHandlers.length === 0) {
+		        Y.log("Attaching base set of event handlers.", "info", "nodeFocusManager");
+				aHandlers.push(oDocument.on("focus", this._onDocFocus, this));
+				aHandlers.push(oDocument.on("mousedown",
+					this._onDocMouseDown, this));
+				aHandlers.push(
+						this.after("keysChange", this._attachKeyHandler));
+				aHandlers.push(
+						this.after("descendantsChange", this._initDescendants));
+				aHandlers.push(
+						this.after(ACTIVE_DESCENDANT_CHANGE,
+								this._afterActiveDescendantChange));
+				//	For performance: defer attaching all key-related event
+				//	handlers until the first time one of the specified
+				//	descendants receives focus.
+				handle = this.after("focusedChange", Y.bind(function (event) {
+					if (event.newVal) {
+				        Y.log("Attaching key event handlers.", "info", "nodeFocusManager");
+						this._attachKeyHandler();
+						//	Detach this "focusedChange" handler so that the
+						//	key-related handlers only get attached once.
+						handle.detach();
+					}
+				}, this));
+				aHandlers.push(handle);
+			}
+			this._eventHandlers = aHandlers;
+		}
+	},
+	//	Protected event handlers
+	/**
+	* @method _onDocMouseDown
+	* @description "mousedown" event handler for the owner document of the
+	* Focus Manager's Node.
+	* @protected
+	* @param event {Object} Object representing the DOM event.
+	*/
+	_onDocMouseDown: function (event) {
+		var oHost = this.get(HOST),
+			oTarget = event.target,
+			bChildNode = oHost.contains(oTarget),
+			node,
+			getFocusable = function (node) {
+				var returnVal = false;
+				if (!node.compareTo(oHost)) {
+					returnVal = Lang.isNumber(node.get(TAB_INDEX)) ? node :
+									getFocusable(node.get("parentNode"));
+				}
+				return returnVal;
+			};
+		if (bChildNode) {
+			//	Check to make sure that the target isn't a child node of one
+			//	of the focusable descendants.
+			node = getFocusable(oTarget);
+			if (node) {
+				oTarget = node;
+			}
+			else if (!node && this.get(FOCUSED)) {
+				//	The target was a non-focusable descendant of the root
+				//	node, so the "focused" attribute should be set to false.
+	 			this._set(FOCUSED, false);
+	 			this._onDocFocus(event);
+			}
+		}
+		if (bChildNode && this._isDescendant(oTarget)) {
+			//	Fix general problem in Webkit: mousing down on a button or an
+			//	anchor element doesn't focus it.
+			//	For all browsers: makes sure that the descendant that
+			//	was the target of the mousedown event is now considered the
+			//	active descendant.
+			this.focus(oTarget);
+		}
+		else if (UA.webkit && this.get(FOCUSED) &&
+			(!bChildNode || (bChildNode && !this._isDescendant(oTarget)))) {
+			//	Fix for Webkit:
+			//	Document doesn't receive focus in Webkit when the user mouses
+			//	down on it, so the "focused" attribute won't get set to the
+			//	correct value.
+			this._set(FOCUSED, false);
+			this._onDocFocus(event);
+		}
+	},
+	/**
+	* @method _onDocFocus
+	* @description "focus" event handler for the owner document of the
+	* Focus Manager's Node.
+	* @protected
+	* @param event {Object} Object representing the DOM event.
+	*/
+	_onDocFocus: function (event) {
+		var oTarget = this._focusTarget || event.target,
+			bFocused = this.get(FOCUSED),
+			focusClass = this.get(FOCUS_CLASS),
+			oFocusedNode = this._focusedNode,
+			bInCollection;
+		if (this._focusTarget) {
+			this._focusTarget = null;
+		}
+		if (this.get(HOST).contains(oTarget)) {
+			//	The target is a descendant of the root Node.
+			bInCollection = this._isDescendant(oTarget);
+			if (!bFocused && bInCollection) {
+				//	The user has focused a focusable descendant.
+				bFocused = true;
+			}
+			else if (bFocused && !bInCollection) {
+				//	The user has focused a child of the root Node that is
+				//	not one of the descendants managed by this Focus Manager
+				//	so clear the currently focused descendant.
+				bFocused = false;
+			}
+		}
+		else {
+			// The target is some other node in the document.
+			bFocused = false;
+		}
+		if (focusClass) {
+			if (oFocusedNode && (oFocusedNode !== oTarget || !bFocused)) {
+				this._removeFocusClass();
+			}
+			if (bInCollection && bFocused) {
+				if (focusClass.fn) {
+					oTarget = focusClass.fn(oTarget);
+					oTarget.addClass(focusClass.className);
+				}
+				else {
+					oTarget.addClass(focusClass);
+				}
+				this._focusedNode = oTarget;
+			}
+		}
+		this._set(FOCUSED, bFocused);
+	},
+	/**
+	* @method _focusNext
+	* @description Keydown event handler that moves focus to the next
+	* enabled descendant.
+	* @protected
+	* @param event {Object} Object representing the DOM event.
+	* @param activeDescendant {Number} Number representing the index of the
+	* next descendant to be focused
+	*/
+	_focusNext: function (event, activeDescendant) {
+		var nActiveDescendant = activeDescendant || this.get(ACTIVE_DESCENDANT),
+			oNode;
+		if (this._isDescendant(event.target) &&
+			(nActiveDescendant <= this._lastNodeIndex)) {
+			nActiveDescendant = nActiveDescendant + 1;
+			if (nActiveDescendant === (this._lastNodeIndex + 1) &&
+				this.get(CIRCULAR)) {
+				nActiveDescendant = 0;
+			}
+			oNode = this._descendants.item(nActiveDescendant);
+			if (oNode.get(DISABLED)) {
+				this._focusNext(event, nActiveDescendant);
+			}
+			else {
+				this.focus(nActiveDescendant);
+			}
+		}
+		this._preventScroll(event);
+	},
+	/**
+	* @method _focusPrevious
+	* @description Keydown event handler that moves focus to the previous
+	* enabled descendant.
+	* @protected
+	* @param event {Object} Object representing the DOM event.
+	* @param activeDescendant {Number} Number representing the index of the
+	* next descendant to be focused.
+	*/
+	_focusPrevious: function (event, activeDescendant) {
+		var nActiveDescendant = activeDescendant || this.get(ACTIVE_DESCENDANT),
+			oNode;
+		if (this._isDescendant(event.target) && nActiveDescendant >= 0) {
+			nActiveDescendant = nActiveDescendant - 1;
+			if (nActiveDescendant === -1 && this.get(CIRCULAR)) {
+				nActiveDescendant = this._lastNodeIndex;
+			}
+			oNode = this._descendants.item(nActiveDescendant);
+			if (oNode.get(DISABLED)) {
+				this._focusPrevious(event, nActiveDescendant);
+			}
+			else {
+				this.focus(nActiveDescendant);
+			}
+		}
+		this._preventScroll(event);
+	},
+	/**
+	* @method _afterActiveDescendantChange
+	* @description afterChange event handler for the
+	* "activeDescendant" attribute.
+	* @protected
+	* @param event {Object} Object representing the change event.
+	*/
+	_afterActiveDescendantChange: function (event) {
+		var oNode = this._descendants.item(event.prevVal);
+		if (oNode) {
+			oNode.set(TAB_INDEX, -1);
+		}
+		oNode = this._descendants.item(event.newVal);
+		if (oNode) {
+			oNode.set(TAB_INDEX, 0);
+		}
+	},
+	//	Public methods
+initializer: function (config) {
+		this.start();
+},
+	destructor: function () {
+		this.stop();
+		this.get(HOST).focusManager = null;
+},
+	/**
+	* @method focus
+	* @description Focuses the active descendant and sets the
+	* <code>focused</code> attribute to true.
+	* @param index {Number} Optional. Number representing the index of the
+	* descendant to be set as the active descendant.
+	* @param index {Node} Optional. Node instance representing the
+	* descendant to be set as the active descendant.
+	*/
+	focus: function (index) {
+		if (Lang.isUndefined(index)) {
+			index = this.get(ACTIVE_DESCENDANT);
+		}
+		this.set(ACTIVE_DESCENDANT, index, { src: UI });
+		var oNode = this._descendants.item(this.get(ACTIVE_DESCENDANT));
+		if (oNode) {
+			oNode.focus();
+			//	In Opera focusing a <BUTTON> element programmatically
+			//	will result in the document-level focus event handler
+			//	"_onDocFocus" being called, resulting in the handler
+			//	incorrectly setting the "focused" Attribute to false.  To fix
+			//	this, set a flag ("_focusTarget") that the "_onDocFocus" method
+			//	can look for to properly handle this edge case.
+			if (UA.opera && oNode.get("nodeName").toLowerCase() === "button") {
+				this._focusTarget = oNode;
+			}
+		}
+	},
+	/**
+	* @method blur
+	* @description Blurs the current active descendant and sets the
+	* <code>focused</code> attribute to false.
+	*/
+	blur: function () {
+		var oNode;
+		if (this.get(FOCUSED)) {
+			oNode = this._descendants.item(this.get(ACTIVE_DESCENDANT));
+			if (oNode) {
+				oNode.blur();
+				//	For Opera and Webkit:  Blurring an element in either browser
+				//	doesn't result in another element (such as the document)
+				//	being focused.  Therefore, the "_onDocFocus" method
+				//	responsible for managing the application and removal of the
+				//	focus indicator class name is never called.
+				this._removeFocusClass();
+			}
+			this._set(FOCUSED, false, { src: UI });
+		}
+	},
+	/**
+	* @method start
+	* @description Enables the Focus Manager.
+	*/
+	start: function () {
+		if (this._stopped) {
+			this._initDescendants();
+			this._attachEventHandlers();
+			this._stopped = false;
+		}
+	},
+	/**
+	* @method stop
+	* @description Disables the Focus Manager by detaching all event handlers.
+	*/
+	stop: function () {
+		if (!this._stopped) {
+			this._detachEventHandlers();
+			this._descendants = null;
+			this._focusedNode = null;
+			this._lastNodeIndex = 0;
+			this._stopped = true;
+		}
+	},
+	/**
+	* @method refresh
+	* @description Refreshes the Focus Manager's descendants by re-executing the
+	* CSS selector query specified by the <code>descendants</code> attribute.
+	*/
+	refresh: function () {
+		this._initDescendants();
+	}
+});
+NodeFocusManager.NAME = "nodeFocusManager";
+NodeFocusManager.NS = "focusManager";
+Y.namespace("Plugin");
+Y.Plugin.NodeFocusManager = NodeFocusManager;
+}, '3.0.0b1' ,{requires:['node', 'plugin']});

comt