@Override
  protected Boolean onLoadInBackground(Void... arg) {
    ChatRoomManager manager = new ChatRoomManager(this);

    // Get member and private key from settings
    ChatMember member = Utils.getSetting(this, Const.CHAT_MEMBER, ChatMember.class);
    PrivateKey privateKey = Utils.getPrivateKeyFromSharedPrefs(this);
    if (privateKey == null || member == null) return false;

    // Try to restore already joined chat rooms from server
    try {
      List<ChatRoom> rooms =
          TUMCabeClient.getInstance(this)
              .getMemberRooms(member.getId(), new ChatVerification(privateKey, member));
      manager.replaceIntoRooms(rooms);
      return true;
    } catch (RetrofitError e) {
      Utils.log(e);
      return false;
    }
  }