Method prepareOptions

/**
 * Prepare options for this button.
 *
 * @param   array  $options  The options about this button.
 *
 * @return  void
 *
 * @since  4.0.0
 */
protected function prepareOptions(array &$options)
{
    $options['text'] = $options['text'] ?: 'JTOOLBAR_HELP';
    $options['icon'] = $options['icon'] ?? 'icon-question';
    $options['button_class'] = $options['button_class'] ?? 'btn btn-info';
    $options['onclick'] = $options['onclick'] ?? $this->_getCommand();
    parent::prepareOptions($options);
}