This code produces the attached screenshot for me (Piklist 0.9.9.9, WP 4.6):

piklist('field', array(
  'type' => 'group'
  ,'field' => 'classes'
  ,'label' => 'Classes'
  ,'add_more' => true
  ,'fields' => array(
    array(
      'type' => 'text'
      ,'field' => 'class'
      ,'label' => 'Class Name'
      ,'columns' => 12
    )
    ,array(
      'type' => 'text'
      ,'field' => 'members'
      ,'label' => 'Members'
      ,'columns' => 6
    )
    ,array(
      'type' => 'text'
      ,'field' => 'non_members'
      ,'label' => 'Non-Members'
      ,'columns' => 6
    )
    ,array(
      'type' => 'text'
      ,'field' => 'section'
      // ,'label' => 'Section'
      ,'add_more' => true
      ,'columns' => 12
      ,'attributes' => array('placeholder' => 'Section Name')
      ,'value' => array('Section 1', 'Section 2', 'Section 3')
    )
  )
));

But when you say it “doesn’t seem to work as a child add more,” perhaps you are referring to this limitation:

Currently, default values for our Add-Mores only work on the initial field. We have it on our list to make it work on every add_more.

This means that if you add an additional class, it won’t display the three default sections. Only the initial class will show defaults.

I’m getting started with Piklist and loving it. Thank you!

I came across this same issue of default values not displaying for fields in groups, also mentioned here. I’m running WP 4.5.3, Piklist 0.9.9.9, twentyfifteen theme.

To reproduce, visit Piklist Demos > Add New >

• Common > Lists > Checkbox/Radio Fields > Group Lists
• Add More’s > Single Level > Newsletter Signup

I experienced the missing default value with field types text and file.

Here’s a patch that seems to work, but I’m not familiar with Piklist, so I’m sure you’ll come up with a more integrated implementation.

diff --git includes/class-piklist-form.php includes/class-piklist-form.php
index 19acf4a..01ebc18 100755
--- includes/class-piklist-form.php
+++ includes/class-piklist-form.php
@@ -2539,6 +2539,9 @@ class Piklist_Form
 
       foreach ($field['fields'] as $column)
       {
+        // Record default value
+        $column['default_value'] = $column['value'];
+
         // Set index
         $column['index'] = $index;
 
@@ -2633,6 +2636,12 @@ class Piklist_Form
           }
         }
 
+        // Use default value if necessary
+        if (is_null($column['value']))
+        {
+          $column['value'] = $column['default_value'];
+        }
+
         $content .= self::render_field($column, true);
       }
     }