MKNetworkKit 库的众多强大功能之一是它可以轻松地“冻结”http POST 请求（例如上传到服务器），这些请求可以在网络连接恢复后自动恢复。
详细信息：http: //blog.mugunthkumar.com/products/ios-framework-introducing-mknetworkkit/#Operation_freezing
但是当我结束基于 MKNetworkKit 的应用程序时，我发现 onCompletion 和 onError 块不会在冻结的网络事务上被调用（这显然是一个已知问题），我正在努力如何构建围绕这让用户知道冻结交易何时真正完成。
有没有人处理过这种情况？
什么是让用户忘记网络中断和停机时间的最佳方法，但仍然能够就上次成功连接的时间提供一些反馈？
我想出的最佳答案是继承 MKNetworkOperation，然后覆盖 operationSucceeded 和 operationFailedWithError。当冻结操作完成时，仍会调用这些例程。
从 MKNetworkOperation.h 头文件：
/*!
* @abstract Overridable custom method where you can add your custom business logic error handling
*
* @discussion
* This optional method can be overridden to do custom error handling. Be sure to call [super operationSucceeded] at the last.
* For example, a valid HTTP response (200) like "Item not found in database" might have a custom business error code
* You can override this method and called [super failWithError:customError]; to notify that HTTP call was successful but the method
* ended as a failed call
*
*/
-(void) operationSucceeded;
/*!
* @abstract Overridable custom method where you can add your custom business logic error handling
*
* @discussion
* This optional method can be overridden to do custom error handling. Be sure to call [super operationSucceeded] at the last.
* For example, a invalid HTTP response (401) like "Unauthorized" might be a valid case in your app.
* You can override this method and called [super operationSucceeded]; to notify that HTTP call failed but the method
* ended as a success call. For example, Facebook login failed, but to your business implementation, it's not a problem as you
* are going to try alternative login mechanisms.
*
*/
-(void) operationFailedWithError:(NSError*) error;