public override void Refresh()
 {
     if (Categories != null && Products != null)
     {
         maxCuAndFpu.Reset();
         var loader = new CategoriesAndProductsLoader(this, AddMru);
         loader.LoadAsync();
         loader.Loaded += delegate { OnRefreshed(); };
     }
 }
 public override void Load()
 {
     if (Categories == null && Products == null)
     {
         var loader = new CategoriesAndProductsLoader(this, AddMru);
         loader.LoadAsync();
         loader.Loaded += delegate { OnLoaded(); };
     }
 }