PXSubordinateSelector Using the Where - acumatica

Question

I need information on how to use the PXSubordinateSelector attribute with the Where type that you can allegedly set on the attribute. Does anybody know how to use this attribute?
Specifically, I need to filter the selector by a custom field in the EPCompanyTree table if possible. Not sure what tables this selector attribute usese. It seems to be tucked into the Acumatica black box. Something like this:
[PXSubordinateSelector(typeof(Where<EPCompanyTree.customField, Equal<{somevalue}>>))]
I've tried setting the Where to an arbitrary filter on the EPCompanyTree.sortorder field but, I'm getting an "is not bound" error when clicking on the lookup.
TIA!

Answer 1

The reason for this error is the defined Search in the GetCommand method of the PXSubordinateSelectorAttribute. Below is the disassembled code of that method:
private static Type GetCommand(Type where)
{
Type whereType = typeof(Where<CREmployee.userID, Equal<Current<AccessInfo.userID>>, Or<EPCompanyTreeMember.workGroupID, Owned<Current<AccessInfo.userID>>>>);
if (where != null)
{
whereType = BqlCommand.Compose(new Type[]
{
typeof(Where2<, >),
typeof(Where<CREmployee.userID, Equal<Current<AccessInfo.userID>>, Or<EPCompanyTreeMember.workGroupID, Owned<Current<AccessInfo.userID>>>>),
typeof(And<>),
where
});
}
return BqlCommand.Compose(new Type[]
{
typeof(Search5<, , , >),
typeof(CREmployee.bAccountID),
typeof(LeftJoin<EPCompanyTreeMember, On<EPCompanyTreeMember.userID, Equal<CREmployee.userID>>>),
whereType,
typeof(Aggregate<GroupBy<CREmployee.acctCD>>)
});
}
As you can see from code the Search is being organized on CREmployee with left joined EPCompanyTreeMember, meanwhile, your code is trying to add a condition on EPCompanyTree field which is not participating in the Search.