Usability issues - Hiding

If we continue to use an icon, how do we toggle through three or more options?

I think it is important for users to have a sense of what their choices are so it becomes challenging and I would be curious as to how this has been resolved in other UIs.

Are there times/circumstances when the open eyeball should be called hide.gif?

Where is the open eyeball or closed eyeball being use in Moodle? Is the the open eyeball or closed eyeball being consistent?

1. Site Administration -> Users -> Authentication -> Manage authentication. Here the open/close eyeball means to activate/desactivate authentication plugins more than show / hide functionalities.
2. Site Administration -> Modules -> Activities -> Manage activities. The hide/show column allows selected modules to be hidden i.e. they do not appear in any course "Add an activity" dropdown menu and cannot be used in any course. To hide a module, click the eye icon so that it changes to a closed eye.
3. Site Administration -> Modules -> Blocks -> Manage blocks. The hide/show column allows selected blocks to be hidden i.e. they do not appear in any course "Add a block" dropdown menu and cannot be used in any course. To hide a block, click the eye icon so that it changes to a closed eye.
4. Site Administration -> Modules -> Filters -> Manage Filters. If you click the eye icon opposite the filter, it changes to an open eye and you enable that filter.

There is the classic dispute of whether the icon displays the current value or the value to be implemented.