How to reorder meta box position?

Question

I have a custom post type which have a lot of custom field that categories in meta box. The problem is how do I sorting the meta box in the order that I desired?

As I know there is only 'high','core','normal' and 'side' for positioning the meta box, which is not a practical way to sorting the meta box. Let's say if I set 'high' position for two meta boxes, how do I know which one is on the top??

Thanks

Answer 1

In the following example, replace CPT with the post type name, like post, page, book, event, imaginary, foobar...

add_filter( 'get_user_option_meta-box-order_CPT', 'metabox_order' );
function metabox_order( $order ) {
    return array(
        'normal' => join( 
            ",", 
            array(       // vvv  Arrange here as you desire
                'customdiv-{CPT}',
                'authordiv',
                'slugdiv',
            )
        ),
    );
}

Answer 2

Users can drag and drop meta boxes and WordPress will save the order. So, in a sense, the order in which they were originally rendered does not matter.

You know which one comes first because when you call add_meta_box it simply pushes your meta box's args onto a global array called $wp_meta_boxes. Whichever call to add_meta_box came first will be the first meta box.