src/cm/media/js/lib/yui/yui_3.10.3/docs/node-focusmanager/node-focusmanager-button.html
changeset 525 89ef5ed3c48b
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/cm/media/js/lib/yui/yui_3.10.3/docs/node-focusmanager/node-focusmanager-button.html	Tue Jul 16 14:29:46 2013 +0200
@@ -0,0 +1,843 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="utf-8">
+    <title>Example: Accessible Menu Button</title>
+    <link rel="stylesheet" href="http://fonts.googleapis.com/css?family=PT+Sans:400,700,400italic,700italic">
+    <link rel="stylesheet" href="../../build/cssgrids/cssgrids-min.css">
+    <link rel="stylesheet" href="../assets/css/main.css">
+    <link rel="stylesheet" href="../assets/vendor/prettify/prettify-min.css">
+    <link rel="shortcut icon" type="image/png" href="../assets/favicon.png">
+    <script src="../../build/yui/yui-min.js"></script>
+    
+</head>
+<body>
+<!--
+<a href="https://github.com/yui/yui3"><img style="position: absolute; top: 0; right: 0; border: 0;" src="https://s3.amazonaws.com/github/ribbons/forkme_right_darkblue_121621.png" alt="Fork me on GitHub"></a>
+-->
+<div id="doc">
+    <div id="hd">
+        <h1><img src="http://yuilibrary.com/img/yui-logo.png"></h1>
+    </div>
+    
+        <a href="#toc" class="jump">Jump to Table of Contents</a>
+    
+
+            <h1>Example: Accessible Menu Button</h1>
+    <div class="yui3-g">
+        <div class="yui3-u-3-4">
+            <div id="main">
+                <div class="content"><div class="intro">
+    <p>
+    This example illustrates how to use the Focus Manager Node Plugin,
+    Event's <a href="http://yuilibrary.com/yui/docs/api/classes/YUI.html#event_delegate">delegation support</a> and
+    <a href="http://yuilibrary.com/yui/docs/api/classes/YUI.html#event_mouseenter">mouseenter</a> event, along with
+    the <a href="../overlay/index.html">Overlay widget</a> and Node's support for the
+    <a href="http://www.w3.org/TR/wai-aria/">WAI-ARIA Roles and States</a> to
+    create an accessible menu button.
+    </p>
+</div>
+
+<div class="example">
+    <style scoped>
+        /*  The following two styles are necessary to override style rules in the
+            YUI CSS file. */
+
+        .example ul {
+            margin: 0;
+        }
+
+        .example a:hover {
+            text-decoration: none;
+        }
+
+
+        /*  Hide the button and list while it is being transformed into a menu button.  */
+        .yui3-js-enabled .yui3-menubutton-loading #menu-1,
+        .yui3-js-enabled .yui3-menubutton-loading #button-1 {
+            display: none;
+        }
+
+    </style>
+
+    <link rel="stylesheet" href="../assets/node-focusmanager/menubutton.css">
+
+<div class="yui3-menubutton-loading">
+    <a id="button-1" href="#menu-1"><span><span>Move To</span></span></a>
+    <div id="menu-1">
+        <ul>
+            <li><input type="button" name="button-1" value="Inbox"></li>
+            <li><input type="button" name="button-2" value="Archive"></li>
+            <li><input type="button" name="button-3" value="Trash"></li>
+        </ul>
+    </div>
+</div>
+<div id="out">(Accessible Menu Button results here)</div>
+
+<script>
+YUI().use("node-focusmanager", "node-event-simulate", "overlay", function(Y){
+    
+	var menuButton = Y.one("#button-1"),
+        out        = Y.one("#out"),
+		menu;
+		
+	var initMenu = function () {
+
+		menu = new Y.Overlay({
+			contentBox: "#menu-1",
+			visible: false,
+			tabIndex: null
+		});
+
+		menu.render();
+
+
+		Y.one("#menu-1").setStyle("display", "");
+
+		var boundingBox = menu.get("boundingBox"),
+			contentBox = menu.get("contentBox");
+
+		boundingBox.addClass("yui3-buttonmenu");
+		contentBox.addClass("yui3-buttonmenu-content");
+
+
+		// Append a decorator element to the bounding box to render the shadow.
+
+		boundingBox.append('<div class="yui3-menu-shadow"></div>');
+
+
+		//	Apply the ARIA roles, states and properties to the menu.
+
+		boundingBox.setAttrs({
+			role: "menu",
+			"aria-labelledby": menuLabelID
+		});
+
+		boundingBox.all("input").set("role", "menuitem");
+
+
+		//	For NVDA: Add the role of "presentation" to each LI 
+		//	element to prevent NVDA from announcing the 
+		//	"listitem" role.
+
+		boundingBox.all("div,ul,li").set("role", "presentation");
+
+
+		//	Use the FocusManager Node Plugin to manage the focusability
+		//	of each menuitem in the menu.
+
+		contentBox.plug(Y.Plugin.NodeFocusManager, { 
+
+				descendants: "input",
+				keys: { next: "down:40", // Down arrow
+						previous: "down:38" },	// Up arrow
+				focusClass: {
+					className: "yui3-menuitem-active",
+					fn: function (node) {
+						return node.get("parentNode");
+					}
+				},
+				circular: true
+
+			});
+
+
+		//	Subscribe to the change event for the "focused" attribute
+		//	to listen for when the menu initially gains focus, and 
+		//	when the menu has lost focus completely.
+
+		contentBox.focusManager.after("focusedChange", function (event) {
+
+			if (!event.newVal) {	// The menu has lost focus
+
+				//	Set the "activeDescendant" attribute to 0 when the 
+				//	menu is hidden so that the user can tab from the 
+				//	button to the first item in the menu the next time 
+				//	the menu is made visible.
+
+				this.set("activeDescendant", 0);
+
+			}
+
+		});
+
+
+		//	Hide the button's menu if the user presses the escape key
+		//	while focused either on the button or its menu.
+
+		Y.on("key", function () {
+
+			menu.hide();
+			menuButton.focus();				
+
+		}, [menuButton, boundingBox] ,"down:27");
+
+
+		if (Y.UA.ie === 6) {
+
+			//	Set the width and height of the menu's bounding box -  
+			//	this is necessary for IE 6 so that the CSS for the 
+			//	shadow element can simply set the shadow's width and 
+			//	height to 100% to ensure that dimensions of the shadow 
+			//	are always sync'd to the that of its parent menu.
+
+			menu.on("visibleChange", function (event) {
+
+				if (event.newVal) {
+
+					boundingBox.setStyles({ height: "", width: "" });
+
+					boundingBox.setStyles({ 
+						height: (boundingBox.get("offsetHeight") + "px"), 
+						width: (boundingBox.get("offsetWidth") + "px") });
+
+				}
+
+			});
+
+		}
+
+
+		menu.after("visibleChange", function (event) {
+
+			var bVisible = event.newVal;
+
+			//	Focus the first item when the menu is made visible
+			//	to allow users to navigate the menu via the keyboard
+
+			if (bVisible) {
+
+				//	Need to set focus via a timer for Webkit and Opera
+				Y.Lang.later(0, contentBox.focusManager, contentBox.focusManager.focus);
+
+			}
+
+			boundingBox.set("aria-hidden", (!bVisible));
+
+		});				
+
+
+		//	Hide the menu when one of menu items is clicked.
+
+		boundingBox.delegate("click", function (event) {
+
+			out.setHTML("You clicked " + this.one("input").get("value"));
+
+			contentBox.focusManager.blur();
+			menu.hide();
+
+		}, "li");
+
+
+		//	Focus each menuitem as the user moves the mouse over 
+		//	the menu.
+
+		boundingBox.delegate("mouseenter", function (event) {
+
+			var focusManager = contentBox.focusManager;
+
+			if (focusManager.get("focused")) {
+				focusManager.focus(this.one("input"));
+			}
+
+		}, "li");
+
+
+		//	Hide the menu if the user clicks outside of it or if the 
+		//	user doesn't click on the button
+
+		boundingBox.get("ownerDocument").on("mousedown", function (event) {
+
+			var oTarget = event.target;
+
+			if (!oTarget.compareTo(menuButton) && 
+				!menuButton.contains(oTarget) && 
+				!oTarget.compareTo(boundingBox) && 
+				!boundingBox.contains(oTarget)) {
+
+				menu.hide();
+
+			}
+
+		});
+
+	};
+
+
+	menuButton.addClass("yui3-menubutton");
+
+
+	//	Hide the list until it is transformed into a menu
+
+	Y.one("#menu-1").setStyle("display", "none");
+
+
+	//	Remove the "yui3-menubutton-loading" class from the parent container
+	//	now that the necessary YUI dependencies are loaded and the 
+	//	menu button has been skinned.
+
+	menuButton.ancestor(".yui3-menubutton-loading").removeClass("yui3-menubutton-loading");
+
+
+	//	Apply the ARIA roles, states and properties to the anchor.
+
+	menuButton.setAttrs({
+		role: "button",
+		"aria-haspopup": true
+	});
+
+
+	//	Remove the "href" attribute from the anchor element to  
+	//	prevent JAWS and NVDA from reading the value of the "href"
+	//	attribute when the anchor is focused.
+
+	if ((Y.UA.gecko || Y.UA.ie) && navigator.userAgent.indexOf("Windows") > -1) {
+
+		menuButton.removeAttribute("href");
+
+		//	Since the anchor's "href" attribute has been removed, the 
+		//	element will not fire the click event in Firefox when the 
+		//	user presses the enter key.  To fix this, dispatch the 
+		//	"click" event to the anchor when the user presses the 
+		//	enter key.
+
+		Y.on("key", function (event) {
+
+			menuButton.simulate("click");
+
+		}, menuButton, "down:13");
+
+	}
+
+
+	//	Set the "tabIndex" attribute of the anchor element to 0 to 
+	//	place it in the browser's default tab flow.  This is 
+	//	necessary since 1) anchor elements are not in the default 
+	//	tab flow in Opera and 2) removing the "href" attribute  
+	//	prevents the anchor from firing its "click" event 
+	//	in Firefox.
+
+	menuButton.set("tabIndex", 0);
+
+    //  Since there is some intermediary markup (<span>s) between the anchor element with the role 
+    //  of "button" applied and the text label for the anchor - we need to use the 
+    //  "aria-labelledby" attribute to ensure that screen readers announce the text label for the 
+    //  button.
+
+    var menuLabel = menuButton.one("span span"),
+        menuLabelID = Y.stamp(menuLabel);
+
+    menuLabel.set("id", menuLabelID);
+    menuButton.set("aria-labelledby", menuLabelID);
+
+	var showMenu = function (event) {
+
+		//	For performance: Defer the creation of the menu until 
+		//	the first time the button is clicked.
+
+		if (!menu) {
+			initMenu();
+		}
+
+
+		if (!menu.get("visible")) {
+
+	        menu.set("align", {
+	            node: menuButton,
+	            points: [Y.WidgetPositionAlign.TL, Y.WidgetPositionAlign.BL]
+	        });
+
+			menu.show();
+
+		}
+
+		//	Prevent the anchor element from being focused 
+		//	when the users mouses down on it.
+		event.preventDefault();
+
+	}; 
+
+
+	//	Bind both a "mousedown" and "click" event listener to 
+	//	ensure the button's menu can be invoked using both the 
+	//	mouse and the keyboard.
+
+	menuButton.on(["mousedown", "click"], showMenu);
+
+});
+</script>
+
+</div>
+
+<h2 id="setting-up-the-html">Setting Up the HTML</h2>
+
+<p>
+For a menu button, start with an <code>&lt;a&gt;</code> element whose
+<code>href</code> attribute is set to the id of an <code>&lt;div&gt;</code>
+that wraps a list of <code>&lt;input&gt;</code> elements.
+Therefore, without JavaScript and CSS, the menu button is simply an in-page
+link to a set of additional buttons.
+</p>
+
+<pre class="code prettyprint">&lt;div class=&quot;yui3-menubutton-loading&quot;&gt;
+    &lt;a id=&quot;button-1&quot; href=&quot;#menu-1&quot;&gt;&lt;span&gt;&lt;span&gt;Move To&lt;&#x2F;span&gt;&lt;&#x2F;span&gt;&lt;&#x2F;a&gt;
+    &lt;div id=&quot;menu-1&quot;&gt;
+        &lt;ul&gt;
+            &lt;li&gt;&lt;input type=&quot;button&quot; name=&quot;button-1&quot; value=&quot;Inbox&quot;&gt;&lt;&#x2F;li&gt;
+            &lt;li&gt;&lt;input type=&quot;button&quot; name=&quot;button-2&quot; value=&quot;Archive&quot;&gt;&lt;&#x2F;li&gt;
+            &lt;li&gt;&lt;input type=&quot;button&quot; name=&quot;button-3&quot; value=&quot;Trash&quot;&gt;&lt;&#x2F;li&gt;
+        &lt;&#x2F;ul&gt;
+    &lt;&#x2F;div&gt;
+&lt;&#x2F;div&gt;</pre>
+
+
+<h2 id="progressive-enhancement">Progressive Enhancement</h2>
+
+<p>
+To account for the scenario where the user has CSS enabled in their browser but JavaScript
+is disabled, the CSS used to style the menu button will be loaded via JavaScript
+using the YUI instance's <a href="../yui/index.html#loader">built-in Loader</a>.
+</p>
+
+<pre class="code prettyprint">YUI({
+    modules: {
+        &quot;menubuttoncss&quot;: {
+            type: &quot;css&quot;,
+            fullpath: &quot;..&#x2F;assets&#x2F;node-focusmanager&#x2F;menubutton.css&quot;
+        },
+        &quot;menubuttonjs&quot;: {
+            type: &quot;js&quot;,
+            fullpath: &quot;..&#x2F;assets&#x2F;node-focusmanager&#x2F;menubutton.js&quot;,
+            requires: [&quot;menubuttoncss&quot;, &quot;node-focusmanager&quot;, &quot;node-event-simulate&quot;, &quot;overlay&quot;]
+        }
+    }
+}).use(&quot;menubuttonjs&quot;);</pre>
+
+
+<p>
+To prevent the user from seeing a flash unstyled content when JavaScript is enabled,
+a style rule is created using YUI's <code>yui3-js-enabled</code> class name that will temporarily
+hide the markup while the JavaScript and CSS are in the process of loading.  For more on using the
+<code>yui3-js-enabled</code> class name, see the
+<a href="../widget/index.html#progressive">Hiding Progressively Enhanced Markup</a> section of the
+<a href="../widget/index.html">YUI Widget landing page</a>.
+</p>
+
+<pre class="code prettyprint">&#x2F;*  Hide the button and list while it is being transformed into a menu button.  *&#x2F;
+
+.yui3-js-enabled .yui3-menubutton-loading #menu-1,
+.yui3-js-enabled .yui3-menubutton-loading #button-1 {
+    display: none;
+}</pre>
+
+
+<h2 id="aria-support">ARIA Support</h2>
+
+<p>
+Through the use of CSS and JavaScript the HTML for the menu button can be
+transformed into something that looks and behaves like a desktop menu button,
+but users of screen readers won't perceive it as an atomic widget, but rather
+simply as a set of HTML elements.  However, through the application
+of the
+<a href="http://www.w3.org/TR/wai-aria/">WAI-ARIA Roles and States</a>, it is
+possible to improve the semantics of the markup such that users of screen
+readers perceive it as a menu button control.
+</p>
+
+<h2 id="keyboard-functionality">Keyboard Functionality</h2>
+
+<p>
+The keyboard functionality for the button's menu will be provided by the Focus
+Manager Node Plugin.  The Focus Manager's
+<a href="http://yuilibrary.com/yui/docs/api/classes/plugin.NodeFocusManager.html#attr_descendants"><code>descendants</code></a>
+attribute is set to a value of "input", so that only one menuitem in the
+button's menu  is in the browser's default tab flow.  This allows users
+navigating via the keyboard to use the tab key to quickly move into and out of
+the menu.  Once the menu has focus, the user can move focus among each menuitem
+using the up and down arrows keys, as defined by the value of the
+<a href="http://yuilibrary.com/yui/docs/api/classes/plugin.NodeFocusManager.html#attr_keys"><code>keys</code></a>
+attribute.  The
+<a href="http://yuilibrary.com/yui/docs/api/classes/plugin.NodeFocusManager.html#attr_focusClass"><code>focusClass</code></a>
+attribute is used to apply a class of <code>yui-menuitem-active</code> to
+the parent <code>&lt;li&gt;</code> of each
+<code>&lt;input&gt;</code> when it is focused, making it easy to style the
+menuitem's focused state in all browsers.
+
+<pre class="code prettyprint">YUI().use(&quot;*&quot;, function (Y) {
+
+    var menuButton = Y.one(&quot;#button-1&quot;),
+        menu;
+
+
+    var initMenu = function () {
+
+        menu = new Y.Overlay({
+            contentBox: &quot;#menu-1&quot;,
+            visible: false,
+            tabIndex: null
+        });
+
+        menu.render();
+
+
+        Y.one(&quot;#menu-1&quot;).setStyle(&quot;display&quot;, &quot;&quot;);
+
+        var boundingBox = menu.get(&quot;boundingBox&quot;),
+            contentBox = menu.get(&quot;contentBox&quot;);
+
+        boundingBox.addClass(&quot;yui3-buttonmenu&quot;);
+        contentBox.addClass(&quot;yui3-buttonmenu-content&quot;);
+
+
+        &#x2F;&#x2F; Append a decorator element to the bounding box to render the shadow.
+
+        boundingBox.append(&#x27;&lt;div class=&quot;yui3-menu-shadow&quot;&gt;&lt;&#x2F;div&gt;&#x27;);
+
+
+        &#x2F;&#x2F;  Apply the ARIA roles, states and properties to the menu.
+
+        boundingBox.setAttrs({
+            role: &quot;menu&quot;,
+            &quot;aria-labelledby&quot;: menuLabelID
+        });
+
+        boundingBox.all(&quot;input&quot;).set(&quot;role&quot;, &quot;menuitem&quot;);
+
+
+        &#x2F;&#x2F;  For NVDA: Add the role of &quot;presentation&quot; to each LI
+        &#x2F;&#x2F;  element to prevent NVDA from announcing the
+        &#x2F;&#x2F;  &quot;listitem&quot; role.
+
+        boundingBox.all(&quot;div,ul,li&quot;).set(&quot;role&quot;, &quot;presentation&quot;);
+
+
+        &#x2F;&#x2F;  Use the FocusManager Node Plugin to manage the focusability
+        &#x2F;&#x2F;  of each menuitem in the menu.
+
+        contentBox.plug(Y.Plugin.NodeFocusManager, {
+
+                descendants: &quot;input&quot;,
+                keys: { next: &quot;down:40&quot;, &#x2F;&#x2F; Down arrow
+                        previous: &quot;down:38&quot; },  &#x2F;&#x2F; Up arrow
+                focusClass: {
+                    className: &quot;yui3-menuitem-active&quot;,
+                    fn: function (node) {
+                        return node.get(&quot;parentNode&quot;);
+                    }
+                },
+                circular: true
+
+            });
+
+
+        &#x2F;&#x2F;  Subscribe to the change event for the &quot;focused&quot; attribute
+        &#x2F;&#x2F;  to listen for when the menu initially gains focus, and
+        &#x2F;&#x2F;  when the menu has lost focus completely.
+
+        contentBox.focusManager.after(&quot;focusedChange&quot;, function (event) {
+
+            if (!event.newVal) {    &#x2F;&#x2F; The menu has lost focus
+
+                &#x2F;&#x2F;  Set the &quot;activeDescendant&quot; attribute to 0 when the
+                &#x2F;&#x2F;  menu is hidden so that the user can tab from the
+                &#x2F;&#x2F;  button to the first item in the menu the next time
+                &#x2F;&#x2F;  the menu is made visible.
+
+                this.set(&quot;activeDescendant&quot;, 0);
+
+            }
+
+        });
+
+
+        &#x2F;&#x2F;  Hide the button&#x27;s menu if the user presses the escape key
+        &#x2F;&#x2F;  while focused either on the button or its menu.
+
+        Y.on(&quot;key&quot;, function () {
+
+            menu.hide();
+            menuButton.focus();
+
+        }, [menuButton, boundingBox] ,&quot;down:27&quot;);
+
+
+        if (Y.UA.ie === 6) {
+
+            &#x2F;&#x2F;  Set the width and height of the menu&#x27;s bounding box -
+            &#x2F;&#x2F;  this is necessary for IE 6 so that the CSS for the
+            &#x2F;&#x2F;  shadow element can simply set the shadow&#x27;s width and
+            &#x2F;&#x2F;  height to 100% to ensure that dimensions of the shadow
+            &#x2F;&#x2F;  are always sync&#x27;d to the that of its parent menu.
+
+            menu.on(&quot;visibleChange&quot;, function (event) {
+
+                if (event.newVal) {
+
+                    boundingBox.setStyles({ height: &quot;&quot;, width: &quot;&quot; });
+
+                    boundingBox.setStyles({
+                        height: (boundingBox.get(&quot;offsetHeight&quot;) + &quot;px&quot;),
+                        width: (boundingBox.get(&quot;offsetWidth&quot;) + &quot;px&quot;) });
+
+                }
+
+            });
+
+        }
+
+
+        menu.after(&quot;visibleChange&quot;, function (event) {
+
+            var bVisible = event.newVal;
+
+            &#x2F;&#x2F;  Focus the first item when the menu is made visible
+            &#x2F;&#x2F;  to allow users to navigate the menu via the keyboard
+
+            if (bVisible) {
+
+                &#x2F;&#x2F;  Need to set focus via a timer for Webkit and Opera
+                Y.Lang.later(0, contentBox.focusManager, contentBox.focusManager.focus);
+
+            }
+
+            boundingBox.set(&quot;aria-hidden&quot;, (!bVisible));
+
+        });
+
+
+        &#x2F;&#x2F;  Hide the menu when one of menu items is clicked.
+
+        boundingBox.delegate(&quot;click&quot;, function (event) {
+
+            alert(&quot;You clicked &quot; + this.one(&quot;input&quot;).get(&quot;value&quot;));
+
+            contentBox.focusManager.blur();
+            menu.hide();
+
+        }, &quot;li&quot;);
+
+
+        &#x2F;&#x2F;  Focus each menuitem as the user moves the mouse over
+        &#x2F;&#x2F;  the menu.
+
+        boundingBox.delegate(&quot;mouseenter&quot;, function (event) {
+
+            var focusManager = contentBox.focusManager;
+
+            if (focusManager.get(&quot;focused&quot;)) {
+                focusManager.focus(this.one(&quot;input&quot;));
+            }
+
+        }, &quot;li&quot;);
+
+
+        &#x2F;&#x2F;  Hide the menu if the user clicks outside of it or if the
+        &#x2F;&#x2F;  user doesn&#x27;t click on the button
+
+        boundingBox.get(&quot;ownerDocument&quot;).on(&quot;mousedown&quot;, function (event) {
+
+            var oTarget = event.target;
+
+            if (!oTarget.compareTo(menuButton) &amp;&amp;
+                !menuButton.contains(oTarget) &amp;&amp;
+                !oTarget.compareTo(boundingBox) &amp;&amp;
+                !boundingBox.contains(oTarget)) {
+
+                menu.hide();
+
+            }
+
+        });
+
+    };
+
+
+    menuButton.addClass(&quot;yui3-menubutton&quot;);
+
+
+    &#x2F;&#x2F;  Hide the list until it is transformed into a menu
+
+    Y.one(&quot;#menu-1&quot;).setStyle(&quot;display&quot;, &quot;none&quot;);
+
+
+    &#x2F;&#x2F;  Remove the &quot;yui3-menubutton-loading&quot; class from the parent container
+    &#x2F;&#x2F;  now that the necessary YUI dependencies are loaded and the
+    &#x2F;&#x2F;  menu button has been skinned.
+
+    menuButton.ancestor(&quot;.yui3-menubutton-loading&quot;).removeClass(&quot;yui3-menubutton-loading&quot;);
+
+
+    &#x2F;&#x2F;  Apply the ARIA roles, states and properties to the anchor.
+
+    menuButton.setAttrs({
+        role: &quot;button&quot;,
+        &quot;aria-haspopup&quot;: true
+    });
+
+
+    &#x2F;&#x2F;  Remove the &quot;href&quot; attribute from the anchor element to
+    &#x2F;&#x2F;  prevent JAWS and NVDA from reading the value of the &quot;href&quot;
+    &#x2F;&#x2F;  attribute when the anchor is focused.
+
+    if ((Y.UA.gecko || Y.UA.ie) &amp;&amp; navigator.userAgent.indexOf(&quot;Windows&quot;) &gt; -1) {
+
+        menuButton.removeAttribute(&quot;href&quot;);
+
+        &#x2F;&#x2F;  Since the anchor&#x27;s &quot;href&quot; attribute has been removed, the
+        &#x2F;&#x2F;  element will not fire the click event in Firefox when the
+        &#x2F;&#x2F;  user presses the enter key.  To fix this, dispatch the
+        &#x2F;&#x2F;  &quot;click&quot; event to the anchor when the user presses the
+        &#x2F;&#x2F;  enter key.
+
+        Y.on(&quot;key&quot;, function (event) {
+
+            menuButton.simulate(&quot;click&quot;);
+
+        }, menuButton, &quot;down:13&quot;);
+
+    }
+
+
+    &#x2F;&#x2F;  Set the &quot;tabIndex&quot; attribute of the anchor element to 0 to
+    &#x2F;&#x2F;  place it in the browser&#x27;s default tab flow.  This is
+    &#x2F;&#x2F;  necessary since 1) anchor elements are not in the default
+    &#x2F;&#x2F;  tab flow in Opera and 2) removing the &quot;href&quot; attribute
+    &#x2F;&#x2F;  prevents the anchor from firing its &quot;click&quot; event
+    &#x2F;&#x2F;  in Firefox.
+
+    menuButton.set(&quot;tabIndex&quot;, 0);
+
+    &#x2F;&#x2F;  Since there is some intermediary markup (&lt;span&gt;s) between the anchor element with the role
+    &#x2F;&#x2F;  of &quot;button&quot; applied and the text label for the anchor - we need to use the
+    &#x2F;&#x2F;  &quot;aria-labelledby&quot; attribute to ensure that screen readers announce the text label for the
+    &#x2F;&#x2F;  button.
+
+    var menuLabel = menuButton.one(&quot;span span&quot;),
+        menuLabelID = Y.stamp(menuLabel);
+
+    menuLabel.set(&quot;id&quot;, menuLabelID);
+    menuButton.set(&quot;aria-labelledby&quot;, menuLabelID);
+
+    var showMenu = function (event) {
+
+        &#x2F;&#x2F;  For performance: Defer the creation of the menu until
+        &#x2F;&#x2F;  the first time the button is clicked.
+
+        if (!menu) {
+            initMenu();
+        }
+
+
+        if (!menu.get(&quot;visible&quot;)) {
+
+            menu.set(&quot;align&quot;, {
+                node: menuButton,
+                points: [Y.WidgetPositionAlign.TL, Y.WidgetPositionAlign.BL]
+            });
+
+            menu.show();
+
+        }
+
+        &#x2F;&#x2F;  Prevent the anchor element from being focused
+        &#x2F;&#x2F;  when the users mouses down on it.
+        event.preventDefault();
+
+    };
+
+
+    &#x2F;&#x2F;  Bind both a &quot;mousedown&quot; and &quot;click&quot; event listener to
+    &#x2F;&#x2F;  ensure the button&#x27;s menu can be invoked using both the
+    &#x2F;&#x2F;  mouse and the keyboard.
+
+    menuButton.on(&quot;mousedown&quot;, showMenu);
+    menuButton.on(&quot;click&quot;, showMenu);
+
+});</pre>
+
+</div>
+            </div>
+        </div>
+
+        <div class="yui3-u-1-4">
+            <div class="sidebar">
+                
+                    <div id="toc" class="sidebox">
+                        <div class="hd">
+                            <h2 class="no-toc">Table of Contents</h2>
+                        </div>
+
+                        <div class="bd">
+                            <ul class="toc">
+<li>
+<a href="#setting-up-the-html">Setting Up the HTML</a>
+</li>
+<li>
+<a href="#progressive-enhancement">Progressive Enhancement</a>
+</li>
+<li>
+<a href="#aria-support">ARIA Support</a>
+</li>
+<li>
+<a href="#keyboard-functionality">Keyboard Functionality</a>
+</li>
+</ul>
+                        </div>
+                    </div>
+                
+
+                
+                    <div class="sidebox">
+                        <div class="hd">
+                            <h2 class="no-toc">Examples</h2>
+                        </div>
+
+                        <div class="bd">
+                            <ul class="examples">
+                                
+                                    
+                                        <li data-description="Creating an accessible toolbar using the Focus Manager Node Plugin and Node&#x27;s support for the WAI-ARIA Roles and States.">
+                                            <a href="node-focusmanager-toolbar.html">Accessible Toolbar</a>
+                                        </li>
+                                    
+                                
+                                    
+                                        <li data-description="Creating an accessible menu button using the Focus Manager Node Plugin, Event&#x27;s delegation support and mouseenter event, along with the Overlay widget and Node&#x27;s support for the WAI-ARIA Roles and States.">
+                                            <a href="node-focusmanager-button.html">Accessible Menu Button</a>
+                                        </li>
+                                    
+                                
+                            </ul>
+                        </div>
+                    </div>
+                
+
+                
+            </div>
+        </div>
+    </div>
+</div>
+
+<script src="../assets/vendor/prettify/prettify-min.js"></script>
+<script>prettyPrint();</script>
+
+<script>
+YUI.Env.Tests = {
+    examples: [],
+    project: '../assets',
+    assets: '../assets/node-focusmanager',
+    name: 'node-focusmanager-button',
+    title: 'Accessible Menu Button',
+    newWindow: '',
+    auto:  false 
+};
+YUI.Env.Tests.examples.push('node-focusmanager-toolbar');
+YUI.Env.Tests.examples.push('node-focusmanager-button');
+
+</script>
+<script src="../assets/yui/test-runner.js"></script>
+
+
+
+</body>
+</html>