code: public function init()
      {
          $this->setName('buttons');
          if (!isset($this->options['render_summary'])) {
              $this->options['render_summary'] = false;
          }
          $this->setAttribute('class', 'text-right');
          
          $this->add(
              array(
              //'type' => 'Button',
              'type' => 'Core/Spinner-Submit',
              'name' => 'submit',
              'options' => array(
                  'label' => /*@translate*/ 'Save',
              ),
              'attributes' => array(
                  'id' => 'submit',
                  'type' => 'submit',
                  'value' => 'Save',
                  'class' => 'sf-submit btn btn-primary btn-xs'
              ),
              )
          );
          
          $this->add(
              array(
              'type' => 'Button',
              'name' => 'cancel',
              'options' => array(
                  'label' => /*@translate*/ 'Cancel',
              ),
              'attributes' => array(
                  'id' => 'cancel',
                  'type' => 'reset',
                  'value' => 'Cancel',
                  'class' => 'sf-cancel btn btn-default btn-xs'
              ),
              )
          );
      }
docs: Initialize the Buttons of a summary form element.