I recently migrated a WordPress network of two sites from a local MAMP server to an online one. Everything migrated perfectly, except the functionality of the Post-Thumbnail. The meta box is simply not appearing in any site, in any theme across the network.
I’ve tested a few different themes with post-thumbnail enabled, and the result is the same. No metabox is visible! I’m rather stumped, does anyone have suggestions?
The functions.php file for one of the sites is:
if(function_exists('add_theme_support')) {
add_theme_support('post-thumbnails', array( 'page', 'post', 'portfolio' ));
/** Register custom size */
add_image_size('page-image', 620, 620, false);
add_image_size('portfolio-image', 795, 575, true);
add_image_size('portfolio-thumbnail', 135, 94, true);
}
//------enable post thumbnail preview for custom columns
if ( !function_exists('fb_AddThumbColumn') && function_exists('add_theme_support') ) {
// for post and investments
function fb_AddThumbColumn($cols) {
$cols['thumbnail'] = __('Thumbnail');
return $cols;
}
function fb_AddThumbValue($column_name, $post_id) {
$width = (int) 200;
$height = (int) 125;
if ( 'thumbnail' == $column_name ) {
// thumbnail of WP 2.9
$thumbnail_id = get_post_meta( $post_id, '_thumbnail_id', true );
// image from gallery
$attachments = get_children( array('post_parent' => $post_id, 'post_type' => 'attachment', 'post_mime_type' => 'image') );
if ($thumbnail_id)
$thumb = wp_get_attachment_image( $thumbnail_id, array($width, $height), true );
elseif ($attachments) {
foreach ( $attachments as $attachment_id => $attachment ) {
$thumb = wp_get_attachment_image( $attachment_id, array($width, $height), true );
}
}
if ( isset($thumb) && $thumb ) {
echo $thumb;
} else {
echo __('None');
}
}
}
// for posts
add_filter( 'manage_posts_columns', 'fb_AddThumbColumn' );
add_action( 'manage_posts_custom_column', 'fb_AddThumbValue', 10, 2 );
// for portfolio
add_filter( 'manage_portfolio_columns', 'fb_AddThumbColumn' );
add_action( 'manage_portfolio_custom_column', 'fb_AddThumbValue', 10, 2 );
}
*/
function the_post_thumbnail_url($post_id) {
echo wp_get_attachment_url( get_post_thumbnail_id($post_id) );
}
You must switch to
Network Admin
modethen go to
Settings
>Network settings
near the end you’ll find
Upload Settings
>Media upload buttons
I checked
Images
to see theFeatured Image
box appears in my New Post admin page.I had a similar problem with thumbnails when I migrated a WordPress Network.
I’ve fixed it using this code, maybe it can help you. You need to add this code to functions.php
To use this function on the loop, I had added something like this:
Regards.