code: function () {
              var t = this,
                  prefix = t.o.prefix;
  
              var $btnPane = t.$btnPane = $('<div/>', {
                  class: prefix + 'button-pane'
              });
  
              $.each(t.o.btns, function (i, btnGrp) {
                  if (!$.isArray(btnGrp)) {
                      btnGrp = [btnGrp];
                  }
  
                  var $btnGroup = $('<div/>', {
                      class: prefix + 'button-group ' + ((btnGrp.indexOf('fullscreen') >= 0) ? prefix + 'right' : '')
                  });
                  $.each(btnGrp, function (i, btn) {
                      try { // Prevent buildBtn error
                          if (t.isSupportedBtn(btn)) { // It's a supported button
                              $btnGroup.append(t.buildBtn(btn));
                          }
                      } catch (c) {
                      }
                  });
  
                  if ($btnGroup.html().trim().length > 0) {
                      $btnPane.append($btnGroup);
                  }
              });
  
              t.$box.prepend($btnPane);
          }
docs: Build button pane, use o.btns option