code: public void fireChangeEvent() {
  
          String result = "";
          if (m_textbox.getText() != null) {
              if (!m_textbox.getText().equals(m_default)) {
                  result = m_textbox.getText();
              }
          }
  
          ValueChangeEvent.fire(this, result);
  
      }
docs: Represents a value change event.<p>