That makes sense. I was trying to see if part of the condition could get the post info once the select option changes.

Hmmm, there appears to be an a and s key in the array, but it seems to not have anything to do with source order.

Here’s my piklist code:

piklist('field', array(
  'type' => 'group'
  ,'label' => __('Sources')
  ,'description' => __('Any additional sources to cite')
  ,'field' => 'sources_group'
  ,'add_more' => true
  ,'fields' => array(
    array(
      'type' => 'text'
      ,'field' => 'source_title'
      ,'label' => 'Source Title'
      ,'columns' => 12
      ,'attributes' => array(
        'class' => 'large-text'
      )
    )
    ,array(
      'type' => 'text'
      ,'field' => 'source_text'
      ,'label' => 'Source Text'
      ,'columns' => 12
      ,'attributes' => array(
        'class' => 'large-text'
      )
    )
    ,array(
      'type' => 'text'
      ,'field' => 'source_url'
      ,'label' => 'Source URL'
      ,'columns' => 12
      ,'attributes' => array(
        'class' => 'large-text'
      ),
      'validate' => array(
        array(
          'type' => 'url'
        )
      )
    )
  )
));

and the JSON:

{
    "status": "ok",
    "post": {
        "id": 31,
        "type": "post",
        "slug": "testing-a-cited-post",
        "url": "http://localhost:8888/2015/10/26/testing-a-cited-post/",
        "status": "publish",
        "title": "Testing a cited post",
        "title_plain": "Testing a cited post",
        "content": "<p>Body text</p>\n",
        "excerpt": "<p>Hello excerpt here</p>\n",
        "date": "2015-10-26 14:58:10",
        "modified": "2015-10-26 14:58:19",
        "categories": [
            {
                "id": 2,
                "slug": "memos",
                "title": "Memos",
                "description": "",
                "parent": 0,
                "post_count": 2
            }
        ],
        "tags": [],
        "author": {
            "id": 1,
            "slug": "admin",
            "name": "admin",
            "first_name": "",
            "last_name": "",
            "nickname": "admin",
            "url": "",
            "description": ""
        },
        "comments": [],
        "attachments": [],
        "comment_count": 0,
        "comment_status": "open",
        "custom_fields": {
            "media_label": [
                ""
            ],
            "author_name": [
                ""
            ],
            "author_title": [
                ""
            ],
            "author_twitter": [
                ""
            ],
            "demo_add_more": [
                "single"
            ],
            "sources_group": [
                "a:3:{s:12:\"source_title\";a:2:{i:0;s:25:\"Title of source somewhere\";i:1;s:30:\"Title of Source somewhere else\";}s:11:\"source_text\";a:2:{i:0;s:9:\"more text\";i:1;s:9:\"some text\";}s:10:\"source_url\";a:2:{i:0;s:24:\"http://www.somewhere.com\";i:1;s:28:\"http://www.somewhereelse.com\";}}"
            ]
        }
    },
    "previous_url": "http://localhost:8888/2015/10/14/another-post/"
}

Is there a way to expose this in the same array? I’m using this with the JSON API plugin

Great! That worked, now I just need to replace the image, title, and excerpt with the real thing.

 piklist('field', array(
     'type' => 'select'
     ,'field' => 'featured_post_id'
     ,'label' => 'Choose post to feature'
     ,'columns' => 6
     ,'choices' => array('none' => '-') + piklist(
       get_posts(
          array(
           'post_type' => 'post'
           ,'orderby' => 'post_date'
          )
          ,'objects'
        )
        ,array(
          'ID'
          ,'post_title'
        )
     )
   ));

   piklist('field', array(
     'type' => 'html'
     ,'label' => 'Post Selected'
     ,'field' => 'featured_post_preview'
     ,'description' => 'The selected post to be featured'
     ,'value' => '<img src="Post image"/><h2>Post Title</h2><p>Excerpt</p>'
     ,'conditions' => array(
       array(
         'field' => 'featured_post_id'
         ,'value' => 'none'
         ,'compare' => '!='
       )
     )
   ));