Error: A dialog cannot be requested

Hello all,

The below is a follow up question re the below post.

With ​@andriitkachenko help I have almost completed a derived class on “EPApprovalAutomation”. Now I am going to call it in “APInvoiceEntry” graph extension. It works as expected if in the Approval Maps screen (EP205015) the “Reason for Approval” and/or “Reason for Rejection” is set to “Is Not Prompted”. As soon as I set their value to either “Is Required” or “Is Optional” that requires the engine to display the “Enter Reason” dialog, I get this error that “Error: A dialog cannot be requested”.

I tested the “Reassign” that also displays dialog too but this works fine (Acumatica base code added the Approve/Reject actions through the workflow extensions but Reassign action is added in the EPApprovalAutomation class though)

I thought maybe the derived class initialization override causes issue and spent quite bit of time on it but couldn’t find anything wrong with the Derived class. So I commented the full class as it doesn’t exist at all. Then, I just simply copied and pasted the “Approval” view class in my “APInvoiceEntry” graph extension to see if this is what causes problem. Surprisingly with the below code which is identical to Acumatica base code but just placed in a graph extension (just for sake of testing but of course when issue is addressed I will call the custom derived class), I get the exact same error. This is the simple identical code that causes the issue when I click on Approve or Reject with Reason Settings is set to “Is Required” or “Is Optional”:

using PX.Data;
using PX.Objects.AP;
using PX.Objects.EP;
using EPMessages = PX.Objects.EP.Messages;

namespace HCL.ApprovalWorkflow
{
    public class HCLAPInvoiceEntryApprovalWorkflow : PXGraphExtension<APInvoiceEntry>
    {
        public static bool IsActive() => true;

        [PXViewName(EPMessages.Approval)]
        public EPApprovalAutomationWithoutHoldDefaulting<APInvoice, APInvoice.approved, APInvoice.rejected, APInvoice.hold, APSetupApproval> Approval;
    }
}

Any idea what is happening?