How to Update customized fields from SubContract Line to Bills and Adjustment Line while creating AP Bills from SubContract

Hi @ramya15 

Please find the ways to deriving Values of Custom Fields 

Ways:
1. Override methods that are used to create child record
2. Use events
3. Use the PXDefault attribute 

Example:

Use of Methods

[PXOverride]
public virtual ARTran CreateTranFromShipLine(...)
{
    ARTran tran = baseMethod(newdoc, ordertype, operation, orderline, ref shipline);
 
    SOLine line = PXSelect<SOLine,
        Where<SOLine.orderType, Equal<Required<SOLine.orderType>>,
        And<SOLine.orderNbr, Equal<Required<SOLine.orderNbr>>,
        And<SOLine.lineNbr, Equal<Required<SOLine.lineNbr>>>>>>
        .Select(Base, orderline.OrderType, orderline.OrderNbr, orderline.LineNbr);
 
    var value = Base.Caches[typeof(SOLine)].GetValue<SOLineExt.isDeductible>(line);
    Base.Caches[typeof(ARTran)].SetValue<ARTranExt.isDeductible>(tran, value);
    return tran;
}

Use of Events

public virtual void ARTran_IsDeductible_FieldDefaulting(...)
{
    ARTran tran = (ARTran)e.Row;
 
    SOLine line = PXSelect<SOLine,
        Where<SOLine.orderType, Equal<Required<SOLine.orderType>>,
        And<SOLine.orderNbr, Equal<Required<SOLine.orderNbr>>,
        And<SOLine.lineNbr, Equal<Required<SOLine.lineNbr>>>>>>
            .Select(Base, tran.SOOrderType, tran.SOOrderNbr, tran.SOOrderLineNbr);
            
    e.NewValue = Base.Caches[typeof(SOLine)].GetValue<SOLineExt.isDeductible>(line);
}

Use of PXDefaultAttribute

public sealed class ARTranExtAttributes : PXCacheExtension<ARTran>
{
    #region IsDeductible
    public abstract class isDeductible : IBqlField { }
    [PXDBBool]
    [PXDefault(typeof(Search<SOLineExt.isDeductible,
            Where<SOLine.orderType, Equal<ARTran.sOOrderType>,
            And<SOLine.orderNbr, Equal<ARTran.sOOrderNbr>,
            And<SOLine.lineNbr, Equal<ARTran.sOOrderLineNbr>>>>>),
    PersistingCheck = PXPersistingCheck.Nothing)]
    [PXUIField(DisplayName = "Deductible", Visible = true)]
    public bool? IsDeductible
    {
        get;
        set;
    }
 

Hope this help you.

Thanks @Naveen B and @jinin 

Both logics are working. Thank you so much.