Muli Table Lookup ax 2012

public void lookup()
{
 
    Query                   query;
    QueryBuildDataSource    queryBuildDataSourceTable;
    QueryBuildDataSource    queryBuildDataSourceTableDescriptions;
    QueryBuildRange         queryBuildRange;
    //you need to define the multitable, but initalize it AFTER you have defined the query
    //SysTableLookup          sysTableLookup  = SysTableLookup::newParameters(tableNum(UnitOfMeasure), ctrl);
    SysMultiTableLookup sysTableLookup;
    query = new Query();
     super();
    queryBuildDataSourceTable = query.addDataSource(tableNum(VendTable));
    //join the translation table so we can get a description of the UOM
    queryBuildDataSourceTableDescriptions = queryBuildDataSourceTable.addDataSource(tableNum(DirPartyTable));
    queryBuildDataSourceTableDescriptions.joinMode(JoinMode::InnerJoin);
    queryBuildDataSourceTableDescriptions.relations(false);
    queryBuildDataSourceTableDescriptions.addLink(fieldNum(VendTable, Party),fieldNum(DirPartyTable, RecId));

    //filter by the unit class being passed
    queryBuildRange = queryBuildDataSourceTable.addRange(fieldNum(VendTable, Party));
    ///queryBuildRange.value(queryValue(unitClass));
    //define multiple table lookup query
    sysTableLookup  = SysMultiTableLookup::newParameters(this, query);
    //add which fields will be displayed to the user (symbol + desc.)
    sysTableLookup.addLookupfield(fieldNum(VendTable, AccountNum),1 );
    sysTableLookup.addLookupfield(fieldNum(DirPartyTable, Name),2,true);
    //do not use for multi table
    //sysTableLookup.parmQuery(query);
    sysTableLookup.performFormLookup();
}


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public void lookup()
{
    Query                   query = new Query();
    QueryBuildDataSource    qbds;
    QueryBuildDataSource    qbdsJoin;
    SysTableLookup          sysTableLookup = sysTableLookup::newParameters(         tableNum(VendTable), this);
    ;

    qbds= query.addDataSource( tableNum(VendTable));
    qbdsJoin= qbds.addDataSource( tableNum(DirPartyTable));
    qbdsJoin.relations( false);
    qbdsJoin.fields().dynamic(NoYes::Yes);
    qbdsJoin.addLink( fieldNum(VendTable, Party), fieldNum(DirPartyTable, RecId));
    qbdsJoin.joinMode(JoinMode::InnerJoin);

    sysTableLookup.parmQuery(query);
    sysTableLookup.addLookupfield( fieldNum(VendTable, AccountNum), true);
    sysTableLookup.addLookupfield( fieldNum(VendTable, VendGroup), true);
    sysTableLookup.addLookupfield( fieldNum(VendTable, Party));
    sysTableLookup.performFormLookup();
}