public ActionResult ActivityCreate(string activityname, string address, string city, DateTime datetime)
        {
            ViewData["ActivityName"] = activityname;
            ViewData["Address"]      = address;
            ViewData["City"]         = city;
            ViewData["DateTime"]     = datetime;

            Activity activity = new Activity(activityname, address, city, datetime);

            activityLogic.pushToDB(activity);

            return(RedirectToAction("Index", "Home"));
        }