code: public Button createCloseButton() {
  
          Button button = new Button(CmsVaadinUtils.getMessageText(org.opencms.ui.Messages.GUI_BUTTON_CLOSE_DIALOG_0));
          button.setWidth("150px");
          button.addClickListener(new ClickListener() {
  
              private static final long serialVersionUID = 1L;
  
              public void buttonClick(ClickEvent event) {
  
                  m_context.finish(Lists.newArrayList(m_context.getResources().get(0).getStructureId()));
              }
          });
          return button;
      }
docs: Creates a close button for child dialogs.<p>
  
  @return the close button