Magento 2 – How to Move Cart to Navigation Section

Add the following line into yourtheme/layout/default.xml

<move element="top.search" destination="navigation.sections" after="catalog.topnav" />

Copy sections.phtml from module-theme/view/frontend/templates/html/sections.phtml to yourtheme/templates/html/sections.phtml

Now open this file and put the following line of code after class="section-items" DIV

 <?php echo $block->getChildHtml('topSearch'); ?>

This is working for me.

You will need to do a bit of restyling with CSS and possibly make HTML changes to the cart template but here is how you can move the cart to the end of the navigation in Magento RWD theme.

In your theme's layout file add the following:

<default>
    <reference name="header">
        <action method="unsetChild">
            <name>minicart_head</name>
        </action>
    </reference>
    <reference name="catalog.topnav">
        <action method="insert">
            <name>minicart_head</name>
        </action>
    </reference>
</default>

This will move the block from the header block into the navigation block. You then need to copy the template "page/html/topmenu.phtml" into your theme and output the "minicart_head" child block within an li.

<?php $_menu = $this->getHtml('level-top') ?>

<?php if($_menu): ?>
    <nav id="nav">
        <ol class="nav-primary">
            <?php echo $_menu ?>
            <li class="header-minicart">
                <?php echo $this->getChildHtml('minicart_head'); ?>
            </li>
        </ol>
    </nav>
<?php endif ?>

See below screenshot of it working in RWD. As mentioned you will need to make some CSS changes.