I was trying to do the same thing a while ago. Couldn’t figure out how to do it natively in ACF so I just made a normal PHP array, sorted it, then looped through it.
Full credit to the following (my solution is basically these stuck together):
http://stackoverflow.com/questions/5498718/how-to-sort-associative-array-using-sub-field-of-contained-associative-arrays-in
https://www.advancedcustomfields.com/resources/repeater/
<?php
// check if the repeater field has rows of data
if( have_rows('person_repeater') ):
$personArray = get_field('person_repeater');
function callback( $a, $b ) {
if ( $a['person_group'] > $b['person_group'] ) {
return 1;
} else if ( $a['person_group'] < $b['person_group'] ) {
return -1;
}
return 0;
}
uasort( $personArray, 'callback' );
foreach ($personArray as $person) {
?>
Group name: <?php echo $person['person_group']; ?>, Person Name: <?php echo $person['person_name']; ?><br>
<?php
}
else :
// no rows found
endif;
?>
