Sub-Navigation on Custom Page

Question

I made a custom page called resources (qa-page-resources-default.php) and 4 sub-pages (qa-page-resources-<custom subpage name>.php).

Everything works well, but I'm trying to add a sub-navigation menu (like the admin section, for example).

So I alter $qa_content['navigation']['sub'] but it won't show anything.

Altering $qa_content['title'] or $qa_content['custom'] works well.

How do I fix this?

Comments

I altered the navigation before preparing the content. This was the problem.