         realm = try! Realm()
 
         feedConversationsNotificationToken = feedConversations.addNotificationBlock({ [weak self] (change: RealmCollectionChange) in
-
+            let predicate = NSPredicate(format: "hasUnreadMessages = true")
+            if let unreadConversations = self?.feedConversations.filter(predicate) {
+                if unreadConversations.count > 0 {
+                    self?.navigationItem.rightBarButtonItem = self?.clearBarButtonItem
+                }
+            }
         })
 
         feedConversationsTableView.registerNib(UINib(nibName: feedConversationCellID, bundle: nil), forCellReuseIdentifier: feedConversationCellID)


    @IBOutlet weak var feedConversationsTableView: UITableView!

    var realm: Realm!

    var haveUnreadMessages = false {

        println("deinit FeedConversations")
    }

    @objc private func clear(sender: UIBarButtonItem) {

    }

    override func viewDidLoad() {
        super.viewDidLoad()

