procedure TfrmOrcamento.btnSalvarClick(Sender: TObject);
var
    i : integer; 
    vValor : Double;
begin    
    for i := 0 to Pred(listaOrcamento.Count) do
        begin
              vValor:=vValor+
              TfrmTipoOrc(listaOrcamento.ListItems[i].Components[0]).edValor.Value;
        end;
end;