Insert value checkbox in x++

Insert value checkbox in x++ :

public boolean modified()

{

    boolean     ret;

    Amount     _DPPFaktur, _PPNFaktur, _PPhFaktur;

    container   _Cont;

    ret = super();

    if (GG_FPJVoucher_Voucher.text() != "")

    {

        _Cont   = element.getVoucherInfo(GG_FPJVoucher_Voucher.text());

        GG_FPJVoucher_CustAccount.text(conpeek(_Cont, 1));

        GG_FPJVoucher_VoucherDate.dateValue(conpeek(_Cont, 2));

        GG_FPJVoucher_JournalId.text(conpeek(_Cont, 3));

        GG_FPJVoucher_CurrencyCode.text(conpeek(_Cont, 4));

        GG_FPJVoucher_TotalVoucherAmount.realValue(conpeek(_Cont, 5));

        GG_FPJVoucher_FPJExchRate.realValue(conpeek(_Cont, 6));

        GG_FPJVoucher_PPhExchRate.realValue(conpeek(_Cont, 7));

        GG_FPJVoucher_FPJVoucherType.selection(conpeek(_Cont, 8));

        GGSalesID.text(conpeek(_Cont, 9));

        PPNPercent.realValue(conpeek(_Cont, 10));

        PPhPercent.realValue(conpeek(_Cont, 11));

        Berikat.value(conpeek(_Cont, 12));

        [_DPPFaktur, _PPNFaktur, _PPhFaktur]    = element.calculateAmountFaktur(GG_FPJVoucher_Voucher.text(), conpeek(_Cont, 9));

        element.calculateDPP_VAT_PPh();

        OthFaktur.allowEdit(Element.GetOthFaktur(GG_FPJVoucher_Voucher.text()));

       

        // added by adit

        if(GG_Fpjvoucher::FindVoucher(GG_FPJVoucher_Voucher.text()).UangMuka == noyes::Yes)

        {

       Advance.value(noyes::Yes);

        }       

       

        // ended by adit

    }

    return ret;

}