Wordpress在帖子页面上创建一个新标签 - 插件

I was wondering if you could help me with my plugin. I want to have another tab on the post creator page for example like the AddToAny plugin.

As shown in this picture:

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First you must know how to do a Custom Post Type. Here you have official docs : https://codex.wordpress.org/Post_Types

Second, you must know how to add a meta box. Here you have the official docs: https://codex.wordpress.org/Function_Reference/add_meta_box

And here there is a good tutorial about meta boxes : http://code.tutsplus.com/tutorials/how-to-create-custom-wordpress-writemeta-boxes--wp-20336