public function metaboxSave($value, int $post_id)
    {
        $this->setValue($value);

        if (! $this->getOption('multiple', false)) {
            // Store single value.
            $this->saveSingleValue($this->getRawValue(), $post_id);
        } else {
            // Store multiple values.
            $this->saveMultipleValue($this->getRawValue(), $post_id);
        }
    }