How to make Customer Class ID available in Business Events for AR302000 (Payments and Applications)

Hi everyone,

I’m trying to create a Business Event for the Payments and Applications screen (AR302000) in Acumatica, and I need to use Customer Class ID as a trigger/filter. Here’s my situation:

1. Current setup:

   • I extended the ARPayment DAC with a runtime-only field (PXFormula) to retrieve Customer.CustomerClassID:

    

   [PXString(10, IsUnicode = true)]
[PXUIField(DisplayName = "Customer Class ID", IsReadOnly = true)]
[PXFormula(typeof(Selector<ARPayment.customerID, Customer.customerClassID>))]
public string UsrCustomerClassID { get; set; }


   • The field shows up in DAC Browser under ARPaymentExt.

   • It works at runtime in the UI, and I can see the correct value when debugging.

2. Problem:

   • In Business Events, when I select the Table = Document (ARPayment), my field UsrCustomerClassID does not appear in the field list.

   • I understand this is because the field is calculated at runtime and does not exist in the database, so the BE engine cannot query it.

   • Attempts to use [PXDBScalar] failed with errors like:

      

     Unknown column 'ARPayment_ARPayment.CustomerID' in 'where clause'


     due to table aliasing issues in the BE SQL query.

Has anyone found a supported or easier way to make CustomerClassID accessible in Business Events for ARPayment (AR302000) without adding a DB column?

Is there a workaround to either expose calculated fields or join Customer table in the BE engine?

Thanks

Jacky