@hube2, thanks for your quick reply, I now see what’s going on. Two things:
Firstly, the issue has obviously always been there, but only PHP 7.4 shows a notice.
Secondly, maybe to help others:
I have set up a field as yes/no toggle with ‘no’ as default value. Now when I create a new post and ‘no’ is already the right value for this field, then it won’t be created in the database on saving the post—as long as you don’t set it to ‘yes’, update the post, and set it back to ‘no’ again.
So my solution here is to check if the field exists at all, and if not, assume it is ‘no’:
$field_object = get_field_object( 'p_props_' . $grp . '_' . $v );
if ( !$field_object ) :
// Field doesn’t exist --> false
// ...
else :
if ( $field_object['type'] == 'true_false' ) :
Again, thank you very much!
