I have a
As described in Official Documentation:
public abstract void onMapLoaded ()
Called when the map has finished rendering. This will only be called once. You must request another callback if you want to be notified again.
This is called on the Android UI thread.
So seems it can't be called while map fragment is hidden. Moreover it newer be called even map is visible but it "is continuously changing and never completes loading due to the user constantly interacting with the map.".