/**
 * Implemenation of hook_reaction
 */
class mymodule_form_context_reaction extends context_reaction {
 function options_form($context) {
     return array('test' => array('#type' => 'value', '#value' => TRUE));
   }
  function options_form_submit($values) {
    return array('test' => 1);
  }
  /**
   * Output a list of active contexts.
   */
  function execute() {
  
  $contexts = context_active_contexts();
   if(empty($contexts)){
     drupal_set_message('contexts is empty');
    }
    
   
   
  }   
   
}