docs: public void init(CmsUpdateUI ui, boolean hasPrev, boolean hasNext) {
  
          m_ui = ui;
  
          if (hasPrev) {
              m_back = getBackButton();
              m_back.addClickListener(new ClickListener() {
  
                  private static final long serialVersionUID = 1L;
  
                  public void buttonClick(ClickEvent event) {
  
                      ui.displayDialog(getPreviousDialog());
                  }
  
              });
              addButton(m_back, true);
          }
  
          if (hasNext) {
              m_ok = getOkButton();
              m_ok.addClickListener(new ClickListener() {
  
                  private static final long serialVersionUID = 1L;
  
                  public void buttonClick(ClickEvent event) {
  
                      if (submitDialog()) {
                          ui.displayDialog(getNextDialog());
                      }
                  }
  
              });
              addButton(m_ok, true);
          }
      }