Custom walker for wp_nav_menu

Hi there,
I’m new to the WP forums and not sure if this is the right place for this post, my apologies if it is.

Description of problem:
I’m trying to output a set of menu items in my footer. Not all, just the ones that belong to a specific parent category. I use the wp_nav_menu() function as shown below:

$args = array(
	'echo'  	 => false,
	'depth'		 => 0,
	'container'  => false,
	'items_wrap' => '',
	'before' 	 => '',
	'walker'	 => new BV_Custom_Nav_Footer
);
echo wp_nav_menu($args);

Problem is that this function outputs its own html. So I’m trying to make my own walker class.

Basically I want the follow HTML markup:

<a href="to1">Link 1</a>
<a href="to2">Link 2</a>
<a href="to3">Link 3</a>

So no wrapper around it, no divs, ul or li. Just the tags with the menu links.

At the moment I have this code in my functions.php file

class BV_Custom_Nav_Footer extends Walker_Nav_Menu {

	function start_lvl( &$output, $depth = 0, $args = array() ) {

	}

	function end_lvl( &$output, $depth = 0, $args = array() ) {

	}

	function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {
		$indent = ( $depth ) ? str_repeat( "\t", $depth ) : '';

		$class_names = '';

		$classes = empty( $item->classes ) ? array() : (array) $item->classes;
		$classes[] = 'menu-item-' . $item->ID;

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

		$id = apply_filters( 'nav_menu_item_id', 'menu-item-'. $item->ID, $item, $args );
		$id = $id ? ' id="' . esc_attr( $id ) . '"' : '';

		$output = "";

		$atts = array();
		$atts['title']  = ! empty( $item->attr_title ) ? $item->attr_title : '';
		$atts['target'] = ! empty( $item->target )     ? $item->target     : '';
		$atts['rel']    = ! empty( $item->xfn )        ? $item->xfn        : '';
		$atts['href']   = ! empty( $item->url )        ? $item->url        : '';

		$atts = apply_filters( 'nav_menu_link_attributes', $atts, $item, $args );

		$attributes = '';
		foreach ( $atts as $attr => $value ) {
			if ( ! empty( $value ) ) {
				$value = ( 'href' === $attr ) ? esc_url( $value ) : esc_attr( $value );
				$attributes .= ' ' . $attr . '="' . $value . '"';
			}
		}

                $item_output = $args->before;
		$item_output .= '<a'. $attributes .'>';
		/** This filter is documented in wp-includes/post-template.php */
		$item_output .= $args->link_before . apply_filters( 'the_title', $item->title, $item->ID ) . $args->link_after;
		$item_output .= '</a>';
                $item_output .= $args->after;

		$output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
	}

	function end_el( &$output, $item, $depth = 0, $args = array() ) {

	}
}

This gives me a PHP Notice: Trying to get property of non-object for lines 49, 52 and 54 which are:

line 49:
$item_output = $args->before;

line 52:
$item_output .= $args->link_before . apply_filters( 'the_title', $item->title, $item->ID ) . $args->link_after;

line 54:
$item_output .= $args->after;

I’m trying to understand how the Walker_Nav_Menu class works but it’s tricky… so I guess any help is appreciated.

——- UPDATE ——–

This is really odd but the $args that are given in the wp_nav_menu is an array, not an object. The walker wouldn’t know what to do with an array… right?

Anyway, converting it to an object at the top of the start_el function made all the errors go away…

$args = (object) $args;