If there are no media attached to a node, tell the user.

[mjordan]

A message like "There are no media associated with this object." would be useful.

[mjordan]

Not sure how we can determine from within the controller that there are no media. The output of the view used to list the media is the same regardless of whether there are media or not:

Array
(
    [#type] => view
    [#name] => media_of
    [#display_id] => page_1
    [#arguments] => Array
        (
            [2] => 1
        )

)

Maybe a solution would be to programmatically add a "no results found" property to the view.