private void GetCollection(BUYCollectionSort collectionSort)
        {
            if (collectionTask != null)
            {
                collectionTask.Cancel();
            }

            UIApplication.SharedApplication.NetworkActivityIndicatorVisible = true;
            collectionTask = client.GetProductsPage(1, collection.CollectionId, collectionSort, (products, page, reachedEnd, error) => {
                UIApplication.SharedApplication.NetworkActivityIndicatorVisible = false;

                if (error == null && products != null)
                {
                    this.products = products;
                    TableView.ReloadData();
                }
                else
                {
                    Console.WriteLine("Error fetching products: {0}", error);
                }
            });
        }
        private void GetCollection(BUYCollectionSort collectionSort)
        {
            if (collectionTask != null) {
                collectionTask.Cancel ();
            }

            UIApplication.SharedApplication.NetworkActivityIndicatorVisible = true;
            collectionTask = client.GetProductsPage (1, collection.CollectionId, collectionSort, (products, page, reachedEnd, error) => {
                UIApplication.SharedApplication.NetworkActivityIndicatorVisible = false;

                if (error == null && products != null) {
                    this.products = products;
                    TableView.ReloadData ();
                } else {
                    Console.WriteLine ("Error fetching products: {0}", error);
                }
            });
        }