Add div's into wordpress navigation - php

Question

I am building a custom wordpress theme using underscores and want to add two div's inside the navigation. I know I have to use a custom Walker, but I don't know exactly how and all i can find is how to customize the list items themselves. But all I need is to div's on top of the generated list.
This is what i get now:
<div class="menu-all-pages-container">
<ul id="primary-menu" class="menu">
<li>Menu item 1</li>
<li>Menu item 1</li>
...etc
</ul>
</div>
What I want to have:
<div class="menu-all-pages-container">
<div id="mydiv"></div>
<div class="button"></div>
<ul id="primary-menu" class="menu">
<li>Menu item 1</li>
<li>Menu item 1</li>
...etc
</ul>
</div>
As I said, I think I need a custom Walker and customize the start_el() function? But I am lost after that..
Thanks in advance :)

Answer 1

You can use wp_nav_menu_items filter. try this:
add_filter('wp_nav_menu','add_custom_nav_elements', 10, 1);
function add_custom_nav_elements( $nav ) {
$elements = '<div id="mydiv"></div><div class="button"></div>';
return $elements . $nav;
}
If you looking for add elemets only for primary menu, try this:
add_filter('wp_nav_menu','add_custom_nav_elements', 10, 2);
function add_custom_nav_elements( $nav, $args ) {
$elements = '<div id="mydiv"></div><div class="button"></div>';
if( $args->theme_location == 'primary' )
$nav = $elements . $nav;
return $nav;
}
And add this in where you want to add menu:
<div class="menu-all-pages-container">
<?php wp_nav_menu(array('theme_location' => 'primary')); ?>
</div>