Add field lookup to extended form

class EZDNRParametersFormEventHandler
{
    [FormDataSourceEventHandler(formDataSourceStr(DNRParameters, RORParameters), FormDataSourceEventType::Initialized)]
    public static void RORParameters_OnInitialized(FormDataSource _sender, FormDataSourceEventArgs _e)
    {
        _sender.object(fieldNum(RORParameters, EZExcessHoursCategoryId)).registerOverrideMethod(
            methodStr(FormDataObject, lookup),
            methodStr(EZDNRParametersFormEventHandler, excessHoursCategoryIdLookup),
            new EZDNRParametersFormEventHandler());
    }

    public void excessHoursCategoryIdLookup(FormStringControl _control)
    {
        QueryBuildDataSource    queryBuildDataSource;
        QueryBuildRange         queryBuildRange;
    
        SysTableLookup sysTableLookup = SysTableLookup::newParameters(tableNum(ProjCategory), _control);
        sysTableLookup.addLookupfield(fieldNum(ProjCategory, CategoryId), true);
        sysTableLookup.addLookupfield(fieldNum(ProjCategory, Name));
    
        Query query = new Query();
        query.addDataSource(tableNum(ProjCategory))
            .addRange(fieldNum(ProjCategory, CategoryType))
            .value(queryValue(ProjCategoryType::Hour));
        sysTableLookup.parmQuery(query);
    
        sysTableLookup.performFormLookup();
    }

}