Hello there,
Thank you for this. I was searching something similar.
As I work with a child theme, the code had to be modified and also needed some corrections. Here is a code working for a child theme :
add_filter('acf/prepare_field/name=slug_field', 'populate_flag_field', 20);
function populate_flag_field($field) {
$choices = array();
$dir = get_stylesheet_directory() . '/flags';
$files = scandir($dir);
if ($files) {
foreach ($files as $file) {
if (is_dir($dir . '/' . $file)) {
continue;
}
$file_info = pathinfo($file);
if ($file_info['extension'] != 'png') {
continue;
}
$label = $file_info['filename'];
$choices[$file] = $label;
}
}
$field['choices'] = $choices;
return $field;
}
add_filter('acf/format_value/name=slug_field', 'format_flag_field', 20, 3);
function format_flag_field($value, $post_id, $field) {
if ($value) {
$value = '<img src="' . get_stylesheet_directory_uri() . '/flags/' . $value . '" />';
}
return $value;
}
