Make custom column sortable

Question

I have a added custom column to a custom post type, and it works fine. I just want it to sort the names by title, so I tried this,

function sortable_custom_columns( $columns ) {
    $columns['custom_column'] = 'title';
    return $columns;
}
add_filter( 'manage_edit-custom_sortable_columns', 'sortable_custom_columns' );

However, that is returning very random sorting. I think it may have to do with the content of the column? Which I render like this;

function location_column_content( $column, $post_id ) {
    switch ( $column ) {
        case 'practice_name':
            $location_post_meta = get_post_meta( $post_id );
            $practice_post_id = $location_post_meta['practice_id'][0];
            echo '<a href="' . get_edit_post_link( $practice_post_id ) . '">' . get_the_title( $practice_post_id ) . '</a>';
            break;
    }

}
add_action( 'manage_sf-location_posts_custom_column', 'location_column_content', 10, 2 );

Does this make sense? Any thoughts here? Thank you

Answer 1

Make sure to change MY_POST_TYPE, MY_CUSTOM_COLUMN and MY_META_KEY to the actual values.

First, add your custom column. Unset the date and set it again to keep it in the last column. You can skip this step.

<?php
function my_manage_MY_POST_TYPE_columns( $columns )
{
    // save date to the variable
    $date = $columns['date'];
    // unset the 'date' column
    unset( $columns['date'] ); 
    // unset any column when necessary
    // unset( $columns['comments'] );

    // add your column as new array element and give it table header text
    $columns['MY_CUSTOM_COLUMN'] = __('Custom Column Header Text');

    $columns['date'] = $date; // set the 'date' column again, after the custom column

    return $columns;
}
?>

Second, make your column sortable using manage_edit-{$post_type}_sortable_columns filter (not documented yet).

<?php
function my_set_sortable_columns( $columns )
{
    $columns['MY_CUSTOM_COLUMN'] = 'MY_CUSTOM_COLUMN';
    return $columns;
}
?>

Third, populate column cells.

<?php
function my_populate_custom_columns( $column, $post_id )
{
    switch ( $column ) {
        case 'MY_CUSTOM_COLUMN':
            echo get_post_meta($post_id, 'MY_META_KEY', true);
            break;
        case 'MAYBE_ANOTHER_CUSTOM_COLUMN':
            // additional code
            break;
    }
}
?>

Now you are ready to actually sort that column.

Note: if you don't check meta_query for empty (non-existent) values, your column will show only the posts having (non-empty) meta value until it will be sorted by another by default or another column

<?php
function my_sort_custom_column_query( $query )
{
    $orderby = $query->get( 'orderby' );

    if ( 'MY_CUSTOM_COLUMN' == $orderby ) {

        $meta_query = array(
            'relation' => 'OR',
            array(
                'key' => 'MY_META_KEY',
                'compare' => 'NOT EXISTS', // see note above
            ),
            array(
                'key' => 'MY_META_KEY',
            ),
        );

        $query->set( 'meta_query', $meta_query );
        $query->set( 'orderby', 'meta_value' );
    }
}
?>

And now let's apply filters and actions. Check if you are not on the front-end, on the right page and the right post type is chosen:

<?php
global $pagenow;

if ( is_admin() && 'edit.php' == $pagenow && 'MY_POST_TYPE' == $_GET['post_type'] ) {

    // manage colunms
    add_filter( 'manage_MY_POST_TYPE_posts_columns', 'my_manage_MY_POST_TYPE_columns' );

    // make columns sortable
    add_filter( 'manage_edit-MY_POST_TYPE_sortable_columns', 'my_set_sortable_columns' );

    // populate column cells
    add_action( 'manage_MY_POST_TYPE_posts_custom_column', 'my_populate_custom_columns', 10, 2 );

    // set query to sort
    add_action( 'pre_get_posts', 'my_sort_custom_column_query' );
}

?>

Answer 2

Make Columns Sortable

By default the new custom columns are not sortable so this makes it hard to find data that you need. To sort the custom columns WordPress has another filter manage_edit-post_sortable_columns you can use to assign which columns are sortable.

When this action is ran the function will pass in a parameter of all the columns which are currently sortable, by adding your new custom columns to this list will now make these columns sortable. The value you give this will be used in the URL so WordPress understands which column to order by.

The following to allow you to sort by the custom column meta.

// Register the column as sortable
function register_sortable_columns( $columns ) {
    $columns['meta'] = 'Custom Column';
    return $columns;
}
add_filter( 'manage_edit-post_sortable_columns', 'register_sortable_columns' );

Answer 3

you need sort table using pre_get_posts. Nice step-by-step instructions on envato tips