var onMenuBarReady = function() {
    // Animation object
    var oAnim;
    
    // Utility function used to setup animation for submenus
    function setupMenuAnimation(p_oMenu) {
        if(!p_oMenu.animationSetup) {
            var aItems = p_oMenu.getItemGroups();
            if(aItems && aItems[0]) {
                var i = aItems[0].length - 1;
                var oSubmenu;
                do {
                    oSubmenu = p_oMenu.getItem(i).cfg.getProperty("submenu");
                    if(oSubmenu) {
                        oSubmenu.beforeShowEvent.subscribe(onMenuBeforeShow, oSubmenu, true);
                        oSubmenu.showEvent.subscribe(onMenuShow, oSubmenu, true);
                    }
                } while(i--);
            }
            p_oMenu.animationSetup = true;
        }
    }
    
    // "beforeshow" event handler for each submenu of the menu bar
    function onMenuBeforeShow(p_sType, p_sArgs, p_oMenu) {
        if(oAnim && oAnim.isAnimated()) {
            oAnim.stop();
            oAnim = null;
        }
        YAHOO.util.Dom.setStyle(this.element, "overflow", "hidden");
        YAHOO.util.Dom.setStyle(this.body, "marginTop", ("-" + this.body.offsetHeight + "px"));
    }
    
    // "show" event handler for each submenu of the menu bar
    function onMenuShow(p_sType, p_sArgs, p_oMenu) {
        oAnim = new YAHOO.util.Anim(this.body, { marginTop: { to: 0 } }, .5);
        oAnim.animate();
        var me = this;
    
        function onTween() {
            me.cfg.refireEvent("iframe");
        }
        function onAnimationComplete() {
            YAHOO.util.Dom.setStyle(me.body, "marginTop", ("0px"));
            YAHOO.util.Dom.setStyle(me.element, "overflow", "visible");
            setupMenuAnimation(me);
        }
    
        /*
        Refire the event handler for the "iframe" 
        configuration property with each tween so that the  
        size and position of the iframe shim remain in sync 
        with the menu.
        */
        if(this.cfg.getProperty("iframe") == true) {
            oAnim.onTween.subscribe(onTween);
        }
        oAnim.onComplete.subscribe(onAnimationComplete);
    }
    
    // "render" event handler for the menu bar
    function onMenuRender(p_sType, p_sArgs, p_oMenu) {
        setupMenuAnimation(p_oMenu);
    }
    
    // Instantiate and render the menu bar
    var oMenuBar = new YAHOO.widget.MenuBar("menu", { autosubmenudisplay:true, hidedelay:750, lazyload:true });
    
    // Subscribe to the "render" event
    oMenuBar.renderEvent.subscribe(onMenuRender, oMenuBar, true);
    oMenuBar.cfg.setProperty("showDelay", 0); 
    oMenuBar.render();
};

// Initialize and render the menu bar when it is available in the DOM
YAHOO.util.Event.onContentReady("menu", onMenuBarReady);