Eigenes Widget inkl. Walkeranpassung

/* Register Navigation */
function register_my_menus() {
	register_nav_menus(
		array(
			'cat_nav' => __( 'Katzen-Navigation'),
		)
	);
}
add_action ('init', 'register_my_menus');

/* Widget: Dein eigenes Widget */
class Toni_Menu_Widget extends WP_Widget {
    function Toni_Menu_Widget() {
        $widget_ops = array('classname' => 'widget_wp_own_nav', 'description' => 'Dieses Widget zeigt die tolle Katzen-Navigation an..' );
        $this->WP_Widget('wp_own_nav', 'Rassekatzen » Katzen Menü', $widget_ops);
    }

    function widget($args, $instance) {
        extract($args, EXTR_SKIP);
		global $post;

        echo $before_widget;

		if($instance['title']) {?><p class="h1"><?php echo $instance['title'] ?></p><?php }

		wp_nav_menu(
			array(
				'menu' => 'cat_navigtion', /* menu name */
				'menu_class' => 'blognavigation',
				'theme_location' => 'cat_nav', /* where in the theme it's assigned */
				'container' => 'false', /* container class */
				'depth' => '1', /* suppress lower levels for now */
				'walker' => new description_walker()
			)
		);

        echo $after_widget;
    }

    function update($new_instance, $old_instance) {
        $instance = $old_instance;
        $instance['title'] = strip_tags($new_instance['title']);

        return $instance;
    }

    function form($instance) {
        $instance = wp_parse_args( (array) $instance, array( 'title' => '') );
        $title = $instance['title'];
    }
}
register_widget('Toni_Menu_Widget');

/* Walker */
class description_walker extends Walker_Nav_Menu {
	function start_el(&$output, $item, $depth, $args) {
		global $wp_query;
		$indent = ( $depth ) ? str_repeat( "\t", $depth ) : '';

		$class_names = $value = '';

		$classes = empty( $item->classes ) ? array() : (array) $item->classes;

		$class_names .= join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item ) );
		$class_names = ' class="'. esc_attr( $class_names ) . '"';

		if(apply_filters( 'the_title', $item->title, $item->ID ) != "divider") {
			$output .= $indent . '<li id="menu-item-'. $item->ID . '"' . $value . $class_names .'>';
		}

		$attributes  = ! empty( $item->attr_title ) ? ' title="'  . esc_attr( $item->attr_title ) .'"' : '';
		$attributes .= ! empty( $item->target )     ? ' target="' . esc_attr( $item->target     ) .'"' : '';
		$attributes .= ! empty( $item->xfn )        ? ' rel="'    . esc_attr( $item->xfn        ) .'"' : '';
		$attributes .= ! empty( $item->url )        ? ' href="'   . esc_attr( $item->url        ) .'"' : '';

		$item_output = $args->before;
		$item_output .= '<a'. $attributes .'>';

		/* Hier das ACF Field einbauen */
		if(get_field('name_des_fields', 'category_'.$item->ID') {
			$item_output .= get_field('name_des_fields', 'category_'.$item->ID');
		}

		$item_output .= $args->link_before .apply_filters( 'the_title', $item->title, $item->ID );
		$item_output .= $args->link_after;
		$item_output .= '</a>';
		$item_output .= $args->after;
		$output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
	}

	function start_lvl(&$output, $depth) {
		$indent = str_repeat("\t", $depth);
		$output .= "\n$indent<ul>\n";
	}

	function display_element( $element, &$children_elements, $max_depth, $depth=0, $args, &$output ) {
		$id_field = $this->db_fields['id'];
		if ( is_object( $args[0] ) ) {
			$args[0]->has_children = ! empty( $children_elements[$element->$id_field] );
		}

		return parent::display_element( $element, $children_elements, $max_depth, $depth, $args, $output );
	}
}