Recently I have to add Aria to Flexy menu. I have attached the code.

//flexy.js
(function($){

	jQuery.fn.flexymenu = function(options){
		var settings = {
			 speed: 300,
			 type: "horizontal",
			 align: "left",
			 indicator: false,
			 hideClickOut: true,
			 submenuTrigger: "hover",
			 showDelay: 0,
			 hideDelay: 0,
			 mobileShowDelay: 0,
			 mobileHideDelay: 0,
			 scrollable: false,
			 scrollableMaxHeight: 400
		}
		$.extend( settings, options );
		
		var bigScreen = false;
		var menu = $(this);
		var lastScreenWidth = windowWidth();
		$(".flexy-menu").wrap("
");
		var menuWrapper = $(".flexy-menu-wrapper");
		
		if(settings.type == "vertical"){
			$(menu).addClass("vertical");
			if(settings.align == "right"){
				$(menu).addClass("right");
			}
		}
		
		if(settings.indicator){
			$(menu).find("li").each(function(){
				if($(this).children("ul").length > 0){
					$(this).append("+");
				}
			});
		}
		
		$(menu).prepend("
MENU
");
		
		screenSize();
		
		$(window).resize(function() {
			if(lastScreenWidth <= 768 && windowWidth() > 768){
				unbindEvents();
				hideCollapse();
				bindHover();
				if(settings.type == "horizontal" && settings.align == "right" && bigScreen == false){
					rightAlignMenu();
					bigScreen = true;
				}
			}
			if(lastScreenWidth > 768 && windowWidth() <= 768){
				unbindEvents();
				showCollapse();
				bindClick();
				if(bigScreen == true){
					rightAlignMenu();
					bigScreen = false;
				}
			}
			lastScreenWidth = windowWidth();
		});
		
		function screenSize(){
			if(windowWidth() <= 768){
				showCollapse();
				bindClick();
				if(bigScreen == true){
					rightAlignMenu();
					bigScreen = false;
				}
			}
			else{
				hideCollapse();
				bindHover();
				if(settings.type == "horizontal" && settings.align == "right" && bigScreen == false){
					rightAlignMenu();
					bigScreen = true;
				}
			}
		}
		
		function bindHover(){
			if (navigator.userAgent.match(/Mobi/i) || window.navigator.msMaxTouchPoints > 0 || settings.submenuTrigger == "click"){						
				$(menu).find("a").on("click touchstart", function(e){
					e.stopPropagation(); 
					e.preventDefault();
					$(this).parent("li").siblings("li").find("ul").stop(true, true).fadeOut(settings.speed);
					if($(this).siblings("ul").css("display") == "none"){
						$(this).siblings("ul").stop(true, true).delay(settings.showDelay).fadeIn(settings.speed);
						return false;
					}
					else{
						$(this).siblings("ul").stop(true, true).delay(settings.hideDelay).fadeOut(settings.speed);
						$(this).siblings("ul").find("ul").stop(true, true).fadeOut(settings.speed);
					}
					window.location.href = $(this).attr("href");
				});
				
				$(menu).find("li").bind("mouseleave", function(){
					$(this).children("ul").stop(true, true).fadeOut(settings.speed);
				});
				
				if(settings.hideClickOut == true){
					$(document).bind("click.menu touchstart.menu", function(ev){
						if($(ev.target).closest(menu).length == 0){
							$(menu).find("ul").fadeOut(settings.speed);
						}
					});
				}
			}
			else{
				$(menu).find("li").bind("mouseenter", function(){
                    //$('.flexy-menu > li').find('ul').hide();//this line is my custom code for tab fixes when hover is done
					$(this).children("ul").stop(true, true).delay(settings.showDelay).fadeIn(settings.speed);
				}).bind("mouseleave", function(){
					$(this).children("ul").stop(true, true).delay(settings.hideDelay).fadeOut(settings.speed);
				});
			}
		}
		
		function bindClick(){
			$(menu).find("li:not(.showhide)").each(function(){
				if($(this).children("ul").length > 0){
					$(this).children("a").on("click", function(){
						if($(this).siblings("ul").css("display") == "none"){
							$(this).siblings("ul").delay(settings.mobileShowDelay).slideDown(settings.speed);
							$(this).parent("li").siblings("li").find("ul").delay(settings.mobileHideDelay).slideUp(settings.speed);
							return false;
						}
						else{
							$(this).siblings("ul").delay(settings.mobileHideDelay).slideUp(settings.speed);
						}
					});
				}
			});
		}
		
		function showCollapse(){
			$(menu).children("li:not(.showhide)").hide(0);
			$(menu).children("li.showhide").show(0).bind("click", function(){
				if($(menu).children("li").is(":hidden")){
					$(menu).children("li").slideDown(settings.speed);
					scrollable(true);
				}
				else{
					$(menu).children("li:not(.showhide)").slideUp(settings.speed);
					$(menu).children("li.showhide").show(0);
					$(menu).find("ul").hide(settings.speed);
					scrollable(false);
				}
			});
		}
		
		function hideCollapse(){
			$(menu).children("li").show(0);
			$(menu).children("li.showhide").hide(0);
			scrollable(false);
		}	
		
		function rightAlignMenu() {
			$(menu).children("li").addClass("right");
			var menuItems = $(menu).children("li");
			$(menu).children("li:not(.showhide)").detach();
			for(var i = menuItems.length; i >= 1; i--){
				$(menu).append(menuItems[i]);
			}		
		}
		
		function unbindEvents(){
			$(menu).find("li, a").unbind();
			$(document).unbind("click.menu touchstart.menu");
			$(menu).find("ul").hide(0);
		}
		
		function windowWidth(){
			return document.documentElement.clientWidth || document.body.clientWidth || window.innerWidth;
		}
		
		function scrollable(flag){
			if(settings.scrollable){
				if(flag){
					$(menuWrapper).css("max-height", settings.scrollableMaxHeight).addClass("scrollable")
				}
				else{
					$(menuWrapper).css("max-height", "auto").removeClass("scrollable")
				}
			}
		}

        //Fixes Aria Stuff
        $('.flexy-menu > li').keydown(function(event){
            if ( event.which == 13 ) {
                if($(this).find('ul').length>0) {
                    var menu_dat=$(this).find('ul');
                    $(menu_dat).show();
                }
            }
        });

        var top_level_links = $('.flexy-menu').find('> li > ul li:last-child a');
        $(top_level_links).blur(function(){
            $('.flexy-menu > li').find('ul').hide();
        });
		
	}
	
}(jQuery));

/*Flexi css*/
@import url(../fontawesome/css/font-awesome.css);
@import url("http://fonts.googleapis.com/css?family=Source+Sans+Pro");
/*******************************************************************************
              Default configuration
*******************************************************************************/
.flexy-menu {
  width: 100%;
  margin: 0;
  padding: 0;
  position: relative;
  float: left;
  list-style: none;
  background: #eee; }

.flexy-menu li {
  display: inline-block;
  margin: 0;
  padding: 0;
  float: left;
  line-height: 20px;
  position: relative; }

.flexy-menu > li > a {
  padding: 20px 22px;
  color: #e3001b;
  text-decoration: none;
  display: block;
  text-transform: none;
  -webkit-transition: color 0.2s linear, background 0.2s linear;
  -moz-transition: color 0.2s linear, background 0.2s linear;
  -o-transition: color 0.2s linear, background 0.2s linear;
  transition: color 0.2s linear, background 0.2s linear; }

.flexy-menu li:hover > a,
.flexy-menu li.active > a {
  background: #555;
  color: #fff; }

/*----------------------------
  Right alignment (item)
----------------------------*/
.flexy-menu li.right {
  float: right; }

.flexy-menu .active {
  background: #b0af9e; }
.flexy-menu a.active {
  color: white; }

/*-----------------------------
  Drop down configuration
-----------------------------*/
.flexy-menu ul,
.flexy-menu ul li ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: none;
  position: absolute;
  z-index: 99999;
  width: 300px;
  background: #eee;
  box-shadow: 0 1px 1px rgba(0, 0, 0, 0.3); }

.flexy-menu ul {
  top: 60px;
  left: 0; }

.flexy-menu ul li ul {
  top: 0;
  left: 100%; }

.flexy-menu ul li {
  clear: both;
  width: 100%;
  border: none; }

.flexy-menu ul li a {
  padding: 10px 20px;
  width: 100%;
  color: #e3001b;
  text-decoration: none;
  display: inline-block;
  float: left;
  clear: both;
  box-sizing: border-box;
  -moz-box-sizing: border-box;
  -webkit-box-sizing: border-box;
  -webkit-transition: color 0.2s linear, background 0.2s linear;
  -moz-transition: color 0.2s linear, background 0.2s linear;
  -o-transition: color 0.2s linear, background 0.2s linear;
  transition: color 0.2s linear, background 0.2s linear; }

/*-----------------------------
  Drop down indicators
-----------------------------*/
.flexy-menu > li .indicator {
  position: absolute;
  color: #e3001b;
  top: 20px;
  right: 8px;
  font-size: 17px; }

.flexy-menu ul > li .indicator {
  top: 10px;
  right: 8px; }

/*------------------
  Preset sizes
------------------*/
.thin > li > a {
  padding: 10px 22px; }

.thin ul {
  top: 40px; }

.thin > li .indicator {
  top: 10px; }

.thick > li > a {
  padding: 40px 22px; }

.thick ul {
  top: 100px; }

.thick > li .indicator {
  top: 40px; }

/*-------------------------
  Icons configuration
-------------------------*/
.flexy-menu i {
  line-height: 20px !important;
  margin-right: 6px;
  font-size: 18px;
  float: left; }

/*------------------------------------
  Collapsible menu configuration
------------------------------------*/
.flexy-menu > li.showhide {
  display: none;
  width: 100%;
  height: 50px;
  cursor: pointer;
  color: #dedede;
  border-bottom: solid 1px rgba(0, 0, 0, 0.1);
  background: #333333; }

.flexy-menu > li.showhide span.title {
  margin: 16px 0 0 25px;
  float: left; }

.flexy-menu > li.showhide span.icon {
  margin: 17px 20px;
  float: right; }

.flexy-menu > li.showhide .icon em {
  margin-bottom: 3px;
  display: block;
  width: 20px;
  height: 2px;
  background: #ccc; }

/*-----------------
  Light Theme
-----------------*/
.light {
  background: #fff;
  border: solid 1px #dfdfdf; }

.light a {
  color: #555 !important; }

.light li:hover > a, .light li.active a {
  background: #555;
  color: #fff !important; }

.light ul, .light ul li ul {
  background: #fff; }

.light > li.showhide {
  background: #fff;
  color: #555 !important; }

.light > li.showhide .icon em {
  background: #555; }

.light li .indicator {
  color: #555; }

.light li:hover > .indicator {
  color: #fff; }

/*------------
  Colors
------------*/
.blue li:hover > a, .blue li.active > a {
  background: #02B8FA;
  color: #fff !important; }

.green li:hover > a, .green li.active > a {
  background: #b0af9e;
  color: #fff !important; }

.red li:hover > a, .red li.active > a {
  background: #cf0404;
  color: #fff !important; }

.orange li:hover > a, .orange li.active > a {
  background: #ff670f;
  color: #fff !important; }

.yellow li:hover > a, .yellow li.active > a {
  background: #febf01;
  color: #444 !important; }

.yellow li .indicator {
  color: #dedede; }

.yellow li:hover > .indicator {
  color: #444; }

.yellow.light li .indicator {
  color: #555; }

.purple li:hover > a, .purple li.active > a {
  background: #A737FA;
  color: #fff !important; }

.pink li:hover > a, .pink li.active > a {
  background: #f82b4c;
  color: #fff !important; }

/*******************************************************************************
              Vertical configuration
*******************************************************************************/
.flexy-menu.vertical {
  width: 200px; }

.flexy-menu.vertical li {
  width: 100%; }

.flexy-menu.vertical li a {
  display: inline-block !important;
  width: 100%;
  padding: 18px 20px 16px;
  box-sizing: border-box;
  -moz-box-sizing: border-box;
  -webkit-box-sizing: border-box; }

.flexy-menu.vertical ul li {
  width: 100%; }

/*--------------------------------
  Drop down on vertical menu
--------------------------------*/
.flexy-menu.vertical ul,
.flexy-menu.vertical ul li ul {
  width: 150px; }

.flexy-menu.vertical ul {
  top: 0;
  left: 100%; }

.flexy-menu.vertical ul li ul {
  top: 0px; }

/*---------------------------------
  Vertical menu on right side 
---------------------------------*/
.flexy-menu.vertical.right {
  float: right !important; }

.flexy-menu.vertical.right ul {
  left: -150px !important; }

/*------------------------------
  Indicator on vertical menu 
------------------------------*/
.flexy-menu.vertical > li .indicator {
  top: 17px;
  right: 15px;
  font-size: 17px; }

.flexy-menu.vertical ul > li .indicator {
  top: 18px;
  right: 15px; }

/*****************************************************************************
              Responsive design
*****************************************************************************/
@media (max-width: 767px) {
  .flexy-menu-wrapper.scrollable {
    overflow-y: auto;
    -webkit-overflow-scrolling: touch; }

  .flexy-menu.vertical {
    width: 100%; }

  .flexy-menu li {
    display: block;
    width: 100%; }

  .flexy-menu > li > a {
    padding-top: 15px;
    padding-bottom: 15px;
    padding-left: 25px; }

  .flexy-menu a {
    width: 100%;
    box-sizing: border-box;
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box; }

  .flexy-menu ul,
  .flexy-menu ul li ul,
  .flexy-menu.vertical ul,
  .flexy-menu.vertical ul li ul {
    width: 100%;
    left: 0;
    border-left: none;
    position: static;
    box-sizing: border-box;
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box; }

  .flexy-menu ul li {
    border-left: none;
    border-right: none; }

  .flexy-menu ul li a,
  .flexy-menu.vertical ul li a {
    padding-top: 10px;
    padding-bottom: 10px; }

  .flexy-menu ul > li > a {
    padding-left: 40px !important; }

  .flexy-menu > li .indicator {
    top: 15px;
    right: 25px;
    font-size: 17px; }

  .flexy-menu ul > li .indicator {
    right: 24px; }

  .flexy-menu.vertical ul > li .indicator {
    top: 10px;
    right: 15px; }

  .flexy-menu > li > ul > li > a {
    padding-left: 40px !important; }

  .flexy-menu > li > ul > li > ul > li > a {
    padding-left: 60px !important; }

  .flexy-menu > li > ul > li > ul > li > ul > li > a {
    padding-left: 80px !important; } }