This method activates a menu item by deactivating the current item, scrolling the new item into view, and, if necessary,making it the active item, and triggering a focus event.

var instance = new jQuery.wijmo.wijmenu();
var value; // Type: any

// Parameters
var event; // Type:  event
var item; // Type:  any

value = instance.activate(event, item);

function activate( 
   event : event,
   item : any
) : any;

//Actives a menu item with "sub-item" class.
$(".selector").wijmenu("activate", null, $(".sub-item"));