Adding Widget to Wordpress Admin Post/Page Edit Sidebar

I'm trying to find the proper way to add a custom widget to the sidebar on the post/page editor page, specifically, in the sidebar under the 'Page Attributes' section. I've been searching various keywords and coming up short. The Wordpress codex docs are limited, so I'm having any luck there either.

If there is a hook that can be used, what is it?

Else, the Wordpress functions needed to add the new control.

I'm guessing that the meta boxes are only displayed under the post section, so that wouldn't be the area I'm looking to edit.

Also, would using the Widget class be the wrong thing to do?

开发者_开发问答I'm developing for version 2.8 or higher.

You should pose that question on https://wordpress.stackexchange.com/

In short: Widgets on the editor pages are not widgets, don't use the frontend widget class for them. They are functions (callbacks) you need to register for the editor pages. You can differ between post and page and in later WP versions between the post type as well.

The function to add the meta box to the editor pages is: add_meta_box