protected function visibilityClasses()
    {
        if (!$this->get_field('widget_header_visibility') || !is_array($this->get_field('widget_header_visibility')) || empty($this->get_field('widget_header_visibility'))) {
            return false;
        }

        $options = array(
            'xs' => 'hidden-xs',
            'sm' => 'hidden-sm',
            'md' => 'hidden-md',
            'lg' => 'hidden-lg'
        );

        $options = apply_filters('Municipio/Widget/Source/NavigationWidget/visibilityClasses', $options);

        $classes = array();

        foreach ($this->get_field('widget_header_visibility') as $device) {
            if (isset($options[$device])) {
                $classes[] = $options[$device];
            }
        }

        if (!empty($classes)) {
            $this->data['widgetWrapperClass'] = array_merge($this->data['widgetWrapperClass'], $classes);

            return true;
        }

        return false;
    }