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['icon'] = $options['icon'] ?? 'icon-square';
    parent::prepareOptions($options);
    $options['doTask'] = $this->_getCommand($this->getUrl());
    $options['selector'] = $options['selector'] ?? 'modal-' . $this->getName();
}