private void btnOrder_Click(Object sender, EventArgs e)
        {
            if (item_list_view_adapter == null)
            {
                item_list_view_adapter = new ItemListViewAdapter(Activity, Resource.Layout.item_list_element, Resource.Id.DescItem, new JavaList <ItemSingle>());
            }

            EditText amount    = (EditText)dialog.FindViewById(Resource.Id.Amount);
            EditText itemName  = (EditText)dialog.FindViewById(Resource.Id.itemName);
            EditText basePrice = (EditText)dialog.FindViewById(Resource.Id.BasePrice);
            EditText discount  = (EditText)dialog.FindViewById(Resource.Id.Discount);
            TextView endprice  = (TextView)dialog.FindViewById(Resource.Id.Endprice);

            if (!amount.Text.Equals(""))
            {
                String      id           = itemName.Text;
                ItemAdapter temp_adapter = (ItemAdapter)actv_Item.Adapter;
                ItemSingle  item         = (ItemSingle)temp_adapter.getItem(id);
                item.quantity = amount.Text;
                item.endprice = endprice.Text;
                item_list_view_adapter.Add(item);
                items_list.Adapter = item_list_view_adapter;
                item_list_view_adapter.NotifyDataSetChanged();
                actv_Item.Text = "";
                dialog.Dismiss();
            }
            else
            {
                Activity.RunOnUiThread(() =>
                {
                    Toast.MakeText(Activity, "Please enter the Amount!", ToastLength.Short).Show();
                });
            }
        }
        private void Item_Order_Popup(String itemID, LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
        {
            View itemOrderPopup = inflater.Inflate(Resource.Layout.Item_Order_Popup, null);

            dialog = new Dialog(container.Context);
            dialog.SetContentView(itemOrderPopup);
            dialog.SetTitle("Order selected Item");
            String     itemDesc  = null;
            ItemSingle item      = item_list_adapter.getItem(itemID);
            EditText   itemName  = (EditText)dialog.FindViewById(Resource.Id.itemName);
            EditText   amount    = (EditText)dialog.FindViewById(Resource.Id.Amount);
            EditText   basePrice = (EditText)dialog.FindViewById(Resource.Id.BasePrice);
            EditText   discount  = (EditText)dialog.FindViewById(Resource.Id.Discount);
            TextView   endprice  = (TextView)dialog.FindViewById(Resource.Id.Endprice);
            Button     btnOrder  = (Button)dialog.FindViewById(Resource.Id.btnOrder);
            Button     btnCancel = (Button)dialog.FindViewById(Resource.Id.btnCancelOrder);

            itemDesc       = item.description;
            itemName.Text  = item.no;
            amount.Text    = "";
            amount.Hint    = "Amount...";
            basePrice.Text = item.unitprice;
            discount.Text  = "";
            discount.Hint  = "Discount...";
            endprice.Text  = "0.00";
            dialog.Show();
            amount.AfterTextChanged += delegate {
                ThreadPool.QueueUserWorkItem(o =>
                {
                    amount_TextChanged(this, null);
                });
            };
            btnOrder.Click += delegate {
                btnOrder_Click(this, null);
            };
        }