Custom fields missing when editing a post

I just install the theme Newspaper (well done, really good).
But if I edit a post (when I activate the WordPress “screen options” custom fields),
only some of the custom-fields appear. Some are missing on the screen even if they exist on the database.

What should I do to be abble to see all the custom field on the wordpress admin panel (like on my old theme). Do you have an idea why some of them doesn’t appear ?

Thanks in advance
Looking forward to read you
Great job.

Different themes may provide different custom fields for use with that theme. If the fields disappear when changing to a stock wordpress theme, then those custom data entry fields were provided by the old theme. You should still be able to add items using the built in custom fields widget from WordPress ?

Hi ! Thanks for the quick answers.

@Lucian I inspected (as you told me) the select menu for custom field but strangly no traces of my custom (_mp3_url) field here too.. (for curiosity, I don’t get why some custom fields are shown in the select, some in a metabox and some are not ? )

@Christopher Simmons or @Lucian, I inspected the function.php of the old theme, no trace of custom-fields definition. If I want a metabox for my custom field should I recreate it ? And if yes where can I do that ? Is there a good way to do it ?

Thanks a lot for your help.
Looking forward to read you (or an other developper angel who wants and can help me :).

<select name="metakeyselect" id="metakeyselect">
<option value="#NONE#">&mdash; Select &mdash;</option>

<option value="dsq_needs_sync">dsq_needs_sync</option>
<option value="dsq_thread_id">dsq_thread_id</option>
<option value="embed">embed</option>
<option value="enclosure">enclosure</option>
<option value="image">image</option>
<option value="post_views_count">post_views_count</option>
<option value="rating">rating</option>
<option value="seo_follow">seo_follow</option>
<option value="seo_noindex">seo_noindex</option>
<option value="skyali_custom-sidebar">skyali_custom-sidebar</option>
<option value="skyali_slider">skyali_slider</option>
<option value="skyali_video">skyali_video</option>
<option value="slide_template">slide_template</option>
<option value="td_homepage_loop">td_homepage_loop</option>
<option value="td_homepage_loop_slide">td_homepage_loop_slide</option>
<option value="td_mega_menu_cat">td_mega_menu_cat</option>
<option value="td_unique_articles">td_unique_articles</option>
<option value="track_shortcode">track_shortcode</option>
<option value="vc_teaser">vc_teaser</option>
<option value="votes">votes</option>
<option value="wpo_campaignid">wpo_campaignid</option>
<option value="wpo_feedid">wpo_feedid</option>
<option value="wpo_sourcepermalink">wpo_sourcepermalink</option></select> 

Thanks a lot for your answer !
I was thinking to try something like this.
I just wonder how advanced custom field plugin will react, i hope it will not delete existing customfield !!! I will try if you say so 🙂

+1 on Advanced Custom Fields…. been using this for a project and it works very well. There is no conflict unless you create a new template with field that has existing field name… which I don’t think it would let you do anyway.