code: public void enableCheckboxesForNotInstalledModules(boolean enable) {
  
          for (Map.Entry<String, CheckBox> entry : m_moduleCheckboxes.entrySet()) {
              String moduleName = entry.getKey();
              CheckBox checkbox = entry.getValue();
              if (!OpenCms.getModuleManager().hasModule(moduleName)) {
                  checkbox.setEnabled(enable);
                  if (!enable) {
                      checkbox.setValue(Boolean.FALSE);
                  }
              }
          }
      }
docs: Enables/disables checkboxes for listed modules which are not installed.<p>
  
  @param enable true if the checkboxes for modules which are not installed should be enabled, false if they should be disabled