Conditionally hide the breadcrumbs

If you want to hide the entire breadcrumb trail, you will want to wrap the call to bcn_display() with an if statement that checks that the current user is logged in (such as checking is_user_logged_in(), or check the appropriate current_user_can() role/capability).

If you want to hide just a specific breadcrumb in the trail from users that are not logged in, you will need to write a function that hooks into the bcn_after_fill action. You’ll want to check if the user is logged in as the first step (see previous paragraph for the two different functions you could use). Next, within this function you will need to loop around the items in the passed in the bcn_breadcrumb_trail object (the member breadcrumbs which is an array of bcn_breadcrumb objects). When you find the breadcrumb you want to remove, use unset to remove the breadcrumb. See https://github.com/mtekk/Breadcrumb-NavXT-BuddyPress-Extensions/blob/master/breadcrumb_navxt_buddypress.php for a reference of how to use bcn_after_fill and how to remove/inject breadcrumbs into a trail.