Lookup Method in AX

public void lookup(FormControl _formControl, str _filterStr)

{

   Query                   query = new Query();

   SysTableLookup          sysTableLookup;

   QueryBuildDataSource    queryBuildDataSource;

   QueryBuildRange     qbr;

   ;

   sysTableLookup = SysTableLookup::newParameters(tablenum(UB_Map),_formControl);

   sysTableLookup.addLookupfield(fieldnum(UB_Map,Cities), true);

 //  sysTableLookup.addLookupfield(fieldnum(SalesLine, ItemName));

  // sysTableLookup.addLookupfield(fieldnum(SalesLine, ItemType));

  

 queryBuildDataSource = query.addDataSource(tablenum(UB_Map));

  qbr =  queryBuildDataSource.addRange(fieldnum(UB_Map, States));

   qbr.value(queryValue(UB_Task_Table1.State));

 //  queryBuildDataSource.addRange(fieldnum(AddressCityTable_BR, CountryId)).value(queryValue(zipCode.CountryRegionId));

   sysTableLookup.parmQuery(query);

   sysTableLookup.performFormLookup();

}