lookup field of a standard form

Custom/Change-standard  lookup field of a standard form using register override method

/// <summary>

/// Extension of SalesTable form.

/// </summary>

[ExtensionOf(formStr(SalesTable))]

final class LSSalesTableFormV1_Extension

{

     /// <summary>

    /// init method.

    /// </summary>

    public void init()

    {

        next init();

        // CR 4526 - start.

        LSParameters    lsParameters;

        boolean         ret;

        FormRun         formRun;

        FormDataSource  salesTable_ds;

        SalesTable      salesTableLoc;

        lsParameters  = LSParameters::find();

        ret           = lsParameters.SalesCumulativeDiscount ? true : false;

        formRun = this;

        salesTable_ds = formRun.dataSource(formDataSourceStr(SalesTable, SalesTable));

        if(LSParameters::find().ExternalItemNumberinSOLine == NoYes::Yes)

        {

            FormStringControl SalesLine_ItemId = this.design().controlName(formControlStr(SalesTable, SalesLine_ItemId));

            SalesLine_ItemId.registerOverrideMethod(methodStr(FormDataObject, lookup), formMethodStr(SalesTable, LSSalesLine_ItemId));

        }

    }

    public void LSSalesLine_ItemId(FormStringControl _formControl)

    {

        Query                   query = new Query();

        QueryBuildDataSource    qbds,qbds2;

        QueryBuildRange         qbr;

        SysTableLookup          sysTableLookup;

 

        qbds = query.addDataSource(tableNum(LSInventTableExternalItem));

        //qbds.addRange(fieldNum(InventTable, ItemType)).value("Item");

        //qbds2 = qbds.addDataSource(tableNum(CustVendExternalItem));

        //qbds2.relations(false);

        //qbds2.joinMode(JoinMode::OuterJoin);

        //qbds2.addLink(fieldNum(CustVendExternalItem, ItemID), fieldNum(InventTable, ItemID));

 

        sysTableLookup = SysTableLookup::newParameters(tableNum(LSInventTableExternalItem), _formControl);

        sysTableLookup.addLookupfield(fieldNum(LSInventTableExternalItem, ItemId));

        sysTableLookup.addLookupfield(fieldNum(LSInventTableExternalItem, NameAlias));

        sysTableLookup.addLookupfield(fieldNum(LSInventTableExternalItem, ItemType));

        //sysTableLookup.addLookupfield(fieldNum(LSInventTableExternalItem, ExternalItemId));

        

        sysTableLookup.parmQuery(query);

        sysTableLookup.performFormLookup();

 

    }

}

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