There is no way of querying that. But the answer suggested by @RafaelC is unnecessary(sorry mate no hard feelings)... your code is already designed so u can know when is visible. See when u start the action mode, a reference to the ActionMode object is saved in your member variable:
mActionMode = activity.startActionMode(mCallback);
Then in your onDestroyActionMode, if you dont have it yet add this line:
mActioinMode=null;
That's it!
Now:
if(mActionMode!=null) //your ActionMode bar is visible
if(mActionMode==null) //your ActinMode bar is not visible.
Hope this helps new coders... Regards :)