关于动态"TDBLookupComboBox"

procedure TForm1.Button4Click(Sender: TObject);
var
  TempADOQuery:TADOquery;
  blnCheck:boolean;
begin
  TempADOQuery:=FieldRecord('tab','field1','field2'); ///////  得到lookup要用到的查询
  blnCheck:=FieldToLkup(TempADOQuery);           ////// 将字段添加到TdbLookupComboBox
end;
function TForm1.FieldRecord(ATabName,AFCode,AFContent:string):TADOQuery;
var
  rstADOQuery:TADOQuery;
  i,intFieldCount:integer;
begin//
  rstADOQuery:=TADOQuery.Create(form1);
  rstADOQuery.Connection := ADOConnection1;
  rstADOQuery.Close;
  rstADOQuery.SQL.Clear;
  rstADOQuery.SQL.Add('SELECT '
                      + AFCode + ' AS CODE, '
                      + AFContent+ ' AS CONTENT '
                      + ' FROM '+ ATabName);
  rstADOQuery.Open;
  result:=rstADOQuery;
end;function TForm1.FieldToLkup(AADOQuery:TADOQuery):boolean;
var
  TPoint:structPoint;
  lkup:TDBLookupComboBox;
  intFieldCount,i:integer;
begin//
  result:=false;
  lkup:=TDBLookupComboBox.Create(form1);
  lkup.Parent:=form1;
  lkup.Left:=200;
  lkup.Top:= 100;
  //lkup.Text:='';   //问题2,在这里,如何不让他初始的字符为TDBLookupComboBox
  lkup.Visible:=true;
  lkup.ListSource:=AADOQuery.DataSource;
  lkup.ListField:='CONTENT';
  lkup.KeyField:='CODE';
  AADOQuery.Next;
  result:=true;
end;问题1:已经给新创建的lkup的KeyFiled赋值了,为什么它还是灰的,不让选
问题2:如何不让他初始的字符为"TDBLookupComboBox"