@Override
        public void onEvent(FriendChangedNotify friendChangedNotify) {
          List<Friend> addedOrUpdatedFriends = friendChangedNotify.getAddedOrUpdatedFriends();
          List<String> myFriendAccounts = new ArrayList<>(addedOrUpdatedFriends.size());
          List<String> friendAccounts = new ArrayList<>(addedOrUpdatedFriends.size());
          List<String> deletedFriendAccounts = friendChangedNotify.getDeletedFriends();

          // 如果在黑名单中,那么不加到好友列表中
          String account;
          for (Friend f : addedOrUpdatedFriends) {
            account = f.getAccount();
            friendMap.put(account, f);
            friendAccounts.add(account);

            if (NIMClient.getService(FriendService.class).isInBlackList(account)) {
              continue;
            }

            myFriendAccounts.add(account);
          }

          // 更新我的好友关系
          if (!myFriendAccounts.isEmpty()) {
            // update cache
            friendAccountSet.addAll(myFriendAccounts);

            // log
            DataCacheManager.Log(myFriendAccounts, "on add friends", UIKitLogTag.FRIEND_CACHE);
          }

          // 通知好友关系更新
          if (!friendAccounts.isEmpty()) {
            for (FriendDataChangedObserver o : friendObservers) {
              o.onAddedOrUpdatedFriends(friendAccounts);
            }
          }

          // 处理被删除的好友关系
          if (!deletedFriendAccounts.isEmpty()) {
            // update cache
            friendAccountSet.removeAll(deletedFriendAccounts);

            for (String a : deletedFriendAccounts) {
              friendMap.remove(a);
            }

            // log
            DataCacheManager.Log(
                deletedFriendAccounts, "on delete friends", UIKitLogTag.FRIEND_CACHE);

            // notify
            for (FriendDataChangedObserver o : friendObservers) {
              o.onDeletedFriends(deletedFriendAccounts);
            }
          }
        }