Sabuj Kundu 20th Nov 2018

We can add new taxonomy to any new custom post types or built-in post types. Same time we can add new admin cols to any admin end post listing using hooks & filters. But sometimes we notice that we add new taxonomy but we can not show them as admin col. To be more specific let me show default post type “post” has a taxonomy “category” and it has option in post type post listing to show category as column in the table. See the below screenshot.
category as post type post listing column

Now, see the below example: I tried to add a new taxonomy “cbxgooglemapcat” for a custom post type “cbxgooglemap” and it doesn’t show the new taxonomy as admin col. What did I do wrong?
https://gist.github.com/manchumahara/7458f0521c0ca5517bbb5c97837f1e2e

Then I was searching and checking the wordpress core codes and found that there is a default argument for initializing taxonomy for ‘show_admin_column’ and that value is by default ‘false’. I did wrong or missed this line

//'show_admin_column' => true, //see this line

I recorded a video describing the issue and it will be more easy to understand