Override Items Per Page in WP Admin for Post Type

Question

I'm trying to override the number of Items Per Page that a user sets in Screen Options for a specific post type (WP Admin only, not the front end). In this case and for a specific post type, I'd like it to list all posts (regardless of user-set limit) when you click on the post type in WP Admin ( edit.php ).

I've searched and tried several filter and action hooks but nothing has worked. I'm confident that it is possible.

• WordPress 4.9.7
• PHP 7.1.17
• Multisite

Thank you, Daniel

EDIT: I forgot to mention - I'm trying to do this from a plugin.

Answer 1

WordPress tries to derive this from the wp_usermeta table if it exists, otherwise it just defaults to 20. You can filter the metavalue and provide a different default - the key may change if on a multisite so you should check the usermeta table if need be.

/**
 * Override pagination settings
 *
 * @param Integer $meta_value
 * @param Integer $user_id
 * @param String $meta_key
 *
 * @return Integer $meta_value
 */
function so51343268( $meta_value, $user_id, $meta_key ) {

    /**
     * The specific meta key is a combination of the post type and keywords.
     * For 'post' it would be: `edit_post_per_page`
     * For 'category' it would be: `edit_category_per_page`
     */
    if( false !== strpos( $meta_key, '_per_page' ) ) {

        /* Object Type Slug => Pagination Override */
        $unpaginated_types = array(
            'post'      => 999,
            'category'  => 4,
        );

        /* Remove prefix and postfix to get the object type */
        $type = rtrim( ltrim( $meta_key, 'edit_' ), '_per_page' );
        if( isset( $unpaginated_types[ $type ] ) ) {
            $meta_value = $unpaginated_types[ $type ];
        }
    }

    return $meta_value;

}
add_filter( 'get_user_metadata', 'so51343268', 10, 3 );