docs: def _init_ui(self):
          """Initial the first UI page.
          - load html from '/' endpoint
          - if <title> is defined, use as windows title
          """
          (content, mimetype) = make_response(self._url_map_to_function('/'))
          try:
              beautifulsoup = BeautifulSoup(content)
              self.window.set_title(beautifulsoup.find('title').string)
          except:
              pass
  
          if self.debug is True:
              print self.app_dir
  
          # Use load_string instead of load_uri because it shows warning.
          self.webkit_web_view.load_string(
              content,
              mime_type=mimetype,
              encoding='utf-8',
              base_uri='/',
          )