docs: public void setSelectedCategories(Collection<CmsCategory> categories) {
  
          for (Entry<CmsCategory, CheckBox> entry : m_checkboxes.entrySet()) {
              entry.getValue().setValue(Boolean.valueOf(categories.contains(entry.getKey())));
              CmsCategory parentCat = (CmsCategory)getParent(entry.getKey());
              if (parentCat != null) {
                  setCollapsed(parentCat, false);
              }
          }
      }