Oops, the URL I wrote above linked to 404. I fixed it to redirect properly.
In my last post, I didn’t explain my solution well enough. I referenced the code of acf-ninja-forms (https://github.com/bostondv/acf-ninja-forms). It uses prepare_field to use the native select field and I followed it.
In my case, add_action is called on __construct (like the post_object field) and append ‘ajax_action’ to $field on prepare_field. While this approach has worked for me, it may be unusual because it doesn’t use the ‘input.js’ of the plugin itself.
I’m going to leave the code unchanged but I’d like to know more about your solution. Could you show me (or us, include future viewers) your sample code or repository?
