Not sure if this has been solved elsewhere but this is how I got rid of the Invalid argument supplied for foreach php warning
<div id=”xx” class=”
<?php $values = get_field(‘xxacf_field’);
if (count($values))
{ foreach ((array) $values as $value )
{if ($k) echo $value; }} ?>
“>
note: if you to have a space before and after your array values add
echo ” “; echo $value; echo ” “;
In this case I was using checkboxes to add style classes to wp pages.
The only way I could get a space between the class names was to add a separate echo to either side of the values
