global $post; in WooCommerce

Question

Is there a reason when using the add_meta_box() callback, that when I do global $post I can't seem to access anything, or get the ID. I'm in WooCommerce, do I need to use global $product instead... if so why?

When I do add_meta_box( 'supplier_package_box', __( 'Supplier', 'supplier' ), 'populate_meta_box' );

In my callback:

function populate_meta_box(){
    global $post
    print_r($post);
    echo '</br>';

$post is always empty... for context I want to check if a post meta exists so I can populate an input box if necessary. :)

Answer 1

You should avoid using global variables where possible. For metaboxes you should use the $post variable that is passed to the callback function instead:

add_meta_box( 'supplier_package_box', __( 'Supplier', 'supplier' ), 'populate_meta_box' );

function populate_meta_box( $post ){
    print_r($post);
}