docs: protected boolean checkvalue(String colorvalue) {
  
          boolean valid = validateColorValue(colorvalue);
          if (valid) {
              if (colorvalue.length() == 4) {
                  char[] chr = colorvalue.toCharArray();
                  for (int i = 1; i < 4; i++) {
                      String foo = String.valueOf(chr[i]);
                      colorvalue = colorvalue.replaceFirst(foo, foo + foo);
                  }
              }
              m_textboxColorValue.setValue(colorvalue, true);
              m_colorField.getElement().getStyle().setBackgroundColor(colorvalue);
              m_colorValue = colorvalue;
          }
          return valid;
      }