:gitee_url: https://gitee.com/mindspore/docs


.. _program_listing_file_include_callback.h:

Program Listing for File callback.h
===================================

|exhale_lsh| :ref:`Return to documentation for file <file_include_callback.h>` (``include/callback.h``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   
   #ifndef MINDSPORE_INCLUDE_API_CALLBACK_CALLBACK_H
   #define MINDSPORE_INCLUDE_API_CALLBACK_CALLBACK_H
   
   #include <cstddef>
   #include <string>
   #include <vector>
   #include <memory>
   #include "include/api/data_type.h"
   #include "include/api/dual_abi_helper.h"
   
   namespace mindspore {
   class Model;
   class ModelImpl;
   class CallbackImpl;
   
   struct TrainCallBackData {
     TrainCallBackData(bool train_mode, int epoch, int step, Model *model): train_mode_(train_mode), epoch_(epoch),
                       step_(step), model_(model) {}
   
     bool train_mode_;       
     unsigned int epoch_;    
     unsigned int step_ = 0; 
     Model *model_;  
   };
   
   enum CallbackRetValue : uint32_t {
     kContinue = 0,
     kStopTraining = 1,
     kExit = 2,
     kUnknownRetValue = 0xFFFFFFFF
   };
   
   class TrainCallBack {
    public:
     virtual ~TrainCallBack() = default;
   
     virtual void Begin(const TrainCallBackData &cb_data) {}
   
     virtual void End(const TrainCallBackData &cb_data) {}
   
     virtual void EpochBegin(const TrainCallBackData &cb_data) {}
   
     virtual CallbackRetValue EpochEnd(const TrainCallBackData &cb_data) { return kContinue; }
   
     virtual void StepBegin(const TrainCallBackData &cb_data) {}
   
     virtual void StepEnd(const TrainCallBackData &cb_data) {}
   
    protected:
     friend class Model;
     friend class ModelImpl;
     CallbackImpl* callback_impl_ = nullptr;
   };
   
   }  // namespace mindspore
   #endif  // MINDSPORE_INCLUDE_API_CALLBACK_CALLBACK_H