BuddyPress.org

Okay, within BP, the plugins_loaded hook is added to nine times. I’m not positive on how WP searches for actions that are added to a given hook once fired, but I assume it is a standard directory search pattern–meaning top down, alphabetical. (Although I have not looked at function do_action to see if my assumption is correct.)

This means that for all activated plugins, once the plugins_loaded event is triggered, WP will first find the added actions to this hook in BuddyPress/bp-activity.php, then /bp-core.php, then finally bp-loader.php. After that, it will begin searching all BP subdirectories beginning with the BuddyPress//bp-activity/ directory.

What does this mean? It means that the single add_action to the plugins_loaded event in /bp-activity.php will be fired first, then the six added actions in /bp-core.php, and finally the single added action in bp-loader.php. This might be the root of the problem.

Since any added actions to the plugins_loaded event will be triggered no matter where they are (assuming a given plugin is activated), it causes an issue if crucial supporting code to a given function is not fired before. There is no reason for the plugins_loaded event to be referenced more than once within BP. The single occurrence of that in function bp_loaded is sufficient. From there all other added actions to the plugins_loaded event should be replaced with bp_init.

Also, no BP-dependent plugin should reference the plugins_loaded event because it will cause a conflict if BuddyPress is deactivated but for some reason that BP-dependent plugin is still active.

Instead, BP-dependent plugins should either reference the bp_init hook, or create their own custom hook.

Refactoring the aforementioned added actions in BP to fire on bp-init instead of plugins_loaded will more than likely not only solve the issue of the bp-set-nav hook not working, but also the bp_setup_root_components hook and the bp_setup_globals hook, and possibly any other hooks that we have not yet discovered are not working.

I also would recommend that priorities be set on all bp-init actions within BP core so as they are fired in the proper sequence and so that any future BP-dependent plugin that comes before “buddypress” alphabetically does not have any of its actions that are added to bp-init fire before others with in BP.