Change base function in Sales Prices

Hi expert.

In this screen, When I choice Customer in Price Type Dropdown then Price Code Field will be visible, opposite I choice All Pricees in Price Type Dropdown then Price Code Field will be invisible. 

Now I want change flow, Price Code Field always visible. I try code below, but not effect. I forecast my code conflict with base function this screen. Please show me some suggestion. Thank you so much.

 var row = (ARSalesPriceFilter)e.Row;
            InvokeBaseHandler?.Invoke(cache, e);
            if (row != null && row.PriceType != null && PriceTypes["All Prices"].Equals(row.PriceType.Trim()))
            {
                PXUIFieldAttribute.SetVisible<ARSalesPriceFilter.priceCode>(cache, null, true);
            }