I have a form that I am filling with default values in hook_form_alter. Some of the fields are in a in a field group and I need to trigger the “add more” button using code.

I figured out how to send a value to the jQuery code via $form['#attached']['js']. I thought I could use that value to run a loop in the jQuery to trigger the “add more” as often as necessary but I only see the field group values twice.

For example if there should be four sets of field group values, I will see the first and second one but not the third or fourth. If I click on the add more button two more times I’ll see them in the form.

Here is the code in the js file:

(function ($, Drupal) {
  // Custom functions and variables can go here
  Drupal.behaviors.example = {
    attach: function (context, settings) {
      // Put your document's onload code here
      //alert(Drupal.settings.example.clicks);
      for (var i = 0; i < Drupal.settings.example.clicks; i++) {
        //alert(i);
        $("#edit-fgm-node-example-form-group-stuff-add-more").trigger("mousedown");
      }
    }
  };
}(jQuery, Drupal));

This where I attach the js file

function example_after_build($form, &$form_state) {
  // TODO: Stuff!  

  $settings['clicks'] = $_SESSION['count_of_items']; //the initial count of times to trigger jquery
  drupal_add_js(['example' => $settings], 'setting');

  // Add our JavaScript file, named after_ajax.js. This file
  // lives in the /js folder inside our module:
  $form['#attached']['js'] = [
    [
      'type' => 'file',
      'data' => drupal_get_path('module', 'example') . '/js/after_ajax.js',
    ],
  ];
  return $form;
}

Any advice on how I could trigger the “add more” multiple times? Or is what I want to do not possible?