Populating meta box with select-list of existing posts, and assigning it to custom post types
I believe this is what you were looking for. I moved back to using a class because what you were using would very easily conflict with someone else’s code who decided to use the function names select_box_add_meta_box(), select_box_content() and/or select_box_save_postdata(), which is reasonably likely. The class name WPSE_85107 is only likely to conflict with somebody … Read more