Walker_Nav_Menu: Items not nested correctly

I want to add “anchor” tag adjacent to every “list item” that has children.

this is my Walker_Nav_Menu class:

class Menu_Walker extends Walker_Nav_Menu {

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

    $ident = str_repeat( "\t", $depth );

    if ( $args->walker->has_children ) {

        $classes="menu-item-has-children menu-item menu-item-" . $item->ID;

        // actual link
        $output .= "$ident<li class=\"$classes\"><a href=\"$item->url\">$item->title</a></li>\n";

        // added tag after
        $output .= "<a class=\"added\" href=\"#\">txt</a>";

    } else {

        $classes="menu-item menu-item-" . $item->ID;

        // actual link
        $output .= "$ident<li class=\"$classes\"><a href=\"$item->url\">$item->title</a></li>\n";
    }
}

This is the structure of the menu in WordPress:

But the output is not nested correctly as you can see in image below:

Please help me fix this problem

You have this problem, because of your code 😉

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

    $ident = str_repeat( "\t", $depth );

    if ( $args->walker->has_children ) {

        $classes="menu-item-has-children menu-item menu-item-" . $item->ID;

        // actual link
        // you SHOULDN'T close the li tag in here
        $output .= "$ident<li class=\"$classes\"><a href=\"$item->url\">$item->title</a></li>\n";

        // added tag after
        $output .= "<a class=\"added\" href=\"#\">txt</a>";

    } else {

        $classes="menu-item menu-item-" . $item->ID;

        // actual link
        // you SHOULDN'T close the li tag in here
        $output .= "$ident<li class=\"$classes\"><a href=\"$item->url\">$item->title</a></li>\n";
    }
}

In your start_el you close the li tag, so children can’t be printed inside of it…