Customising Custom Menus

Hi Guys,

I’m trying to customise the HTML code for the custom menus outputted in wordpress.

I have created a customised menu named ‘Courses List’

I’ve found some code online:
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 ) . ‘”‘;

$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 ) .'”‘ : ”;

$prepend = ‘‘;
$append = ‘‘;
$description = ! empty( $item->description ) ? ‘<span>’.esc_attr( $item->description ).'</span>’ : ”;

if($depth != 0)
{
$description = $append = $prepend = “”;
}

$item_output = $args->before;
$item_output .= ‘<a’. $attributes .’>’;
$item_output .= $args->link_before .$prepend.apply_filters( ‘the_title’, $item->title, $item->ID ).$append;
$item_output .= $description.$args->link_after;
$item_output .= ”;
$item_output .= $args->after;

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

Which apparently replaces the Walker for the menu.

I’ve also got code:
wp_nav_menu( array(
‘container’ =>false,
‘menu_class’ => ‘nav’,
‘menu’ => ‘Courses List’,
‘echo’ => true,
‘before’ => ”,
‘after’ => ”,
‘link_before’ => ”,
‘link_after’ => ”,
‘depth’ => 0,
‘walker’ => new description_walker())
);

Which works, however it outputs at the top of every page.

Now i could manually place this in the theme however would like to do it as a widget.

I’m assuming i have to use:
add_fliter(‘wp_nav_menu’, UNSURE);

How can i get this to work?? really help me.