code: protected function registerPlugin()
      {
          $view = $this->getView();
  
          MultiSelectAsset::register($view);
  
          $id = $this->options['id'];
  
          $options = $this->clientOptions !== false && !empty($this->clientOptions)
              ? Json::encode($this->clientOptions)
              : '';
  
          $js = "jQuery('#$id').multiselect($options);";
          $view->registerJs($js);
      }
docs: Registers MultiSelect Bootstrap plugin and the related events
  @throws InvalidParamException