header.php

<?php wp_nav_menu(array(
    'container' => 'div',
    'container_class' => 'collapse navbar-collapse',
    'menu_class' => 'nav navbar-nav',
)) ?>

output.html

<div class="nav navbar-nav">
    <ul>
        <li class="page_item page-item-2 current_page_item"><a href="http://localhost/~feng/rsdv2-wp/">sample page</a>
        </li>
    </ul>
</div>