How to do it...

1. Open the alExtensibleAppProject folder in Visual Studio Code.
2. In Explorer, select Copy Transaction Dialog.al, and in the Editor, add the following new function:

local procedure SetFromRecordVariant(var FromRecordVariant: Variant)
var
    FromTransactionEntry: Record "Transaction Entry";
    FromPostedTransactionEntry: Record "Posted Transaction Entry";
begin
    case FromType of
        FromType::Transaction:
            begin
                FromTransactionEntry.Get(FromTransactionEntryNo);
                FromRecordVariant := FromTransactionEntry;
            end;
        FromType::"Posted Transaction":
            begin
                FromPostedTransactionEntry.Get(FromTransactionEntryNo);
                FromRecordVariant := FromPostedTransactionEntry;
            end;
    end;
end;

3. Update the GetCopyTransactionParameters() function with the following:
   1. Call the new SetFromRecordVariant() function.
   2. Replace the FromSourceType and FromSourceNo parameters with FromRecordVariant.

Your function should look like this:

procedure GetCopyTransactionParameters(var FromRecordVariant: Variant; var ClearNewTransactionNo: Boolean; var GetNewUnitCost: Boolean)
begin
    SetFromRecordVariant(FromRecordVariant);
    ClearNewTransactionNo := ResetNewTransactionNo;
    GetNewUnitCost := GetUpdatedUnitCost;
end;

4. In Explorer, select Copy Transaction.al and in the Editor, delete the following four functions:
   • CopyTransaction()
   • DoCopyTransaction()
   • CopyFromTransaction()
   • CopyFromPostedTransaction()

Yeah, I know you have an empty codeunit right now. We'll create a new and improved version of it!

5. Add the CopyTransaction() function:

procedure CopyTransaction()
var
    CopyTransactionDialog: Page "Copy Transaction Dialog";
    ClearNewTransactionNo: Boolean;
    GetNewUnitCost: Boolean;
    FromRecordVariant: Variant;
begin
    if CopyTransactionDialog.RunModal() = Action::OK then begin
        CopyTransactionDialog.GetCopyTransactionParameters(FromRecordVariant, ClearNewTransactionNo, GetNewUnitCost);
        DoCopyTransaction(FromRecordVariant, ClearNewTransactionNo, GetNewUnitCost);
    end;
end;

6. Add the DoCopyTransaction() function:

local procedure DoCopyTransaction(var FromRecordVariant: Variant; var ClearNewTransactionNo: Boolean; var GetNewUnitCost: Boolean)
var
    FromRecordRef: RecordRef;
    DataTypeMgmt: Codeunit "Data Type Management";
begin
    DataTypeMgmt.GetRecordRef(FromRecordVariant, FromRecordRef);
    CopyFromSourceRecord(FromRecordRef, ClearNewTransactionNo, GetNewUnitCost);
end;

7. Add the CopyFromSourceRecord() function:

local procedure CopyFromSourceRecord(var FromRecordRef: RecordRef; var ClearNewTransactionNo: Boolean; var GetNewUnitCost: Boolean)
var
    FromTransactionEntry: Record "Transaction Entry";
    FromPostedTransactionEntry: Record "Posted Transaction Entry";
    NewTransaction: Record "Transaction Entry";
begin
    NewTransaction.Init();
    case FromRecordRef.Number() of
        Database::"Transaction Entry":
            begin
                FromRecordRef.SetTable(FromTransactionEntry);
                NewTransaction.TransferFields(FromTransactionEntry, false);
            end;
        Database::"Posted Transaction Entry":
            begin
                FromRecordRef.SetTable(FromPostedTransactionEntry);
                NewTransaction.TransferFields(FromPostedTransactionEntry, false);
            end;
    end;
    if ClearNewTransactionNo then
        NewTransaction."Transaction No." := '';
    if GetNewUnitCost then
        NewTransaction.GetLastDirectUnitCost();
    NewTransaction.Status := NewTransaction.Status::New;
    NewTransaction.Insert(true);
end;

You're done!

You can now deploy your application if you want to try it out. The CopyTransaction() function should work just as it did previously in step 5, only now, we have a single set of code to maintain.