Add ShareThis social icons to WordPress

content.php

<div class="addthis_sharing_toolbox"></div>

setup.php

<?php
/**
 * Proactively resolve domain name asynchronously
 *
 * - ShareThis
 *
 * @link http://dev.chromium.org/developers/design-documents/dns-prefetching Chromium prefetch behavior
 * @link https://developer.mozilla.org/en-US/docs/Controlling_DNS_prefetching Firefox prefetch behavior
 * @return void
 */
function prefix_dns_prefetch_sharethis() {

    // ShareThis
    $share_url = ( is_ssl() ? '//ws' : '//w' ) . '.sharethis.com';
    echo '<link rel="dns-prefetch" href="' . $share_url . '">' . "\n";

}
add_action( 'wp_head', 'prefix_dns_prefetch_sharethis' );





/**
 * Add ShareThis Markup to Footer
 *
 * Leverages async method
 *
 * @link http://support.sharethis.com/customer/portal/articles/475260-examples#sthash.pRR1p8fZ.dpbs
 * @return void
 */
function prefix_sharethis_markup() {

    $share_url = ( is_ssl() ? '//ws' : '//w' ) . '.sharethis.com/button/buttons.js';
    $pub_id    = 'XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX';

    echo "<script type='text/javascript'>" . "\n";
    echo "    var switchTo5x=true;" . "\n";
    echo "    (function() {" . "\n";
    echo "        var stscr = document.createElement('script'); stscr.type = 'text/javascript'; stscr.async = true;" . "\n";
    echo "        stscr.src = '{$share_url}';" . "\n";
    echo "        var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(stscr, s);" . "\n";
    echo "        stscr.onload = stCB;" . "\n";
    echo "        stscr.onreadystatechange = function() { if(stscr.readyState=='loaded') { stCB(); } };" . "\n";
    echo "    })();" . "\n";
    echo "    function stCB(){" . "\n";
    echo "        stLight.options({ publisher:'{$pub_id}', doNotHash: true, doNotCopy: true, hashAddressBar: false });" . "\n";
    echo "    }" . "\n";
    echo "</script>" . "\n";

}
add_action( 'wp_footer', 'prefix_sharethis_markup' );