Unable to sort on menu_order

[sanderdewijs]

Hi,

I have added the menu_order to the admin screen for a CPT. I can make the column sortable and display the values inside the column. However when I click the column header to sort, the sorting action displays an empty list. Can't figure out what is going wrong here:

	'cb' => '<input type="checkbox" />',
	'title' => 'Title',
	'video_type' => 'Type',
	'menu_order' => 'Order',
	'sticky' => 'Sticky',
	'date' => 'Date',
    ));
    $videoPost->sortable(array(
	'sticky' => array('sticky', false),
	'menu_order' => array('menu_order', true),
    ));
    $videoPost->populate_column('menu_order', function($column, $post){
	echo $post->menu_order;
    });
    $videoPost->populate_column('video_type', function($column, $post){
	echo ucfirst(get_field('video_type'));
    });
    $videoPost->populate_column('sticky', function($column, $post){
	if(get_field('sticky')) {
		echo 'Yes';
	}
    }); 

Thank you,
Sander