Online Users block (Part II) - Invisible and Visible Users

In my previous post on the same subject here, I  showed how a user's avatar and username could be made to disappear from the Andy J. Davis' Online Users block. The problem with that feature is that everyone in the online class could opt to be come invisible. If so, then it would be difficult for the administrator or teacher of the course to know exactly how users many had gone invisible on the coursepage.

I have since updated the block to allow the Administrator to see how many visible and invisible users are currently accessing the Moodle site. A teacher who is not an Site administrator, but is  teacher of the course and also a course administrator can also be given the same privileges. Take for example, the image below:


A Student user who has gone invisible
Here we find that Mr Smiley Face is a student who has opted to make himself invisible. He is able to see other students' avatars as long as they did not themselves choose to be invisible. 

Image 1: One invisible lurker
and one visible user. 

Mr Smiley Face student does not, however, know how many lurkers exist on the Moodle coursepage site. For all he knows, he might be the only lurker around. Or, he could be one of ten others lurking around the site.