Vaadin + Springboot + Thread= problem

I Create one click button, and in this click I do this:

private void buscarCaixas() {
        BuscarCaixasPeriodo buscarCaixasPeriodo = new BuscarCaixasPeriodo();
        progresso.setVisible(true);
        progresso.setIndeterminate(true);
        buscarCaixasPeriodo.start();
    }

and this is my code from BuscarCaixasPeriodo:

public class BuscarCaixasPeriodo extends Thread 
    {                      
            public void run()                       
            {              
                UI.getCurrent().access(new Runnable() {
                    @Override
                    public void run() {
                        try{
                            caixasContainer =new BeanItemContainer<CaixaVO>(CaixaVO.class, caixas);        
                            caixasList.setContainerDataSource(caixasContainer);
                            try{
                                caixasContainer.addAll(financeiroService.getCaixasByPeriodo(dtInicial.getValue(), dtFinal.getValue()));
                                caixasList.setPageLength(caixasContainer.size());
                                atualizarDashboard.setEnabled(true);
                                caixasList.setEnabled(true);
                                caixasList.setShowSelectAllButton(new ShowButton() {

                                    @Override
                                    public boolean isShow(String filter, int page) {
                                        return true;
                                    }
                                });
                                caixasList.focus();
                            }catch(Exception e){
                                Notification.show(e.getMessage(), Type.ERROR_MESSAGE);
                            }
                        }catch(Exception e){
                            Utils.showNotification(e.getMessage(), Type.ERROR_MESSAGE, UI.getCurrent().getPage());
                        }
                        progresso.setVisible(false);
                        progresso.setIndeterminate(false);
                    }
                });
            }
    }

So when I click in button, my progress change to indeterminate, and execute my method, but he don`t back to my front until i click in another place (example in one combobox, ou anothr tab) If I wait for 5minutes, the server dont callback to my front.

anyone know why??  

tks

Do you have push enabled? I.e., is your UI annotated with @Push?

No,

Works.. tks (Only put @Push in my ui)