/**
     * page_wiki constructor
     *
     * @param $wiki. Current wiki
     * @param $subwiki. Current subwiki.
     * @param $cm. Current course_module.
     */
    function __construct($wiki, $subwiki, $cm) {
        global $PAGE, $CFG;
        $this->subwiki = $subwiki;
        $this->modcontext = context_module::instance($PAGE->cm->id);

        // initialise wiki renderer
        $this->wikioutput = $PAGE->get_renderer('mod_wiki');
        $PAGE->set_cacheable(true);
        $PAGE->set_cm($cm);
        $PAGE->set_activity_record($wiki);
        // the search box
        $PAGE->set_button(wiki_search_form($cm));
    }

 /**
  * page_wiki constructor
  *
  * @param $wiki. Current wiki
  * @param $subwiki. Current subwiki.
  * @param $cm. Current course_module.
  */
 function __construct($wiki, $subwiki, $cm)
 {
     global $PAGE, $CFG;
     $this->subwiki = $subwiki;
     $this->cm = $cm;
     $this->modcontext = context_module::instance($this->cm->id);
     // initialise wiki renderer
     $this->wikioutput = $PAGE->get_renderer('mod_wiki');
     $PAGE->set_cacheable(true);
     $PAGE->set_cm($cm);
     $PAGE->set_activity_record($wiki);
     // the search box
     if (!empty($subwiki->id)) {
         $search = optional_param('searchstring', null, PARAM_TEXT);
         $PAGE->set_button(wiki_search_form($cm, $search, $subwiki));
     }
 }