text: #pragma once
  
  #include "scroll.h"
  
  class VScroll : public Scroll
  {
  private:
  
  public:
  	VScroll(SDL_Renderer* renderer, SDL_Rect size, int now_value, int max_value, int step_size);
  
  public:
  	void set_step(int step);
  	void shift(int delta);
  
  	virtual void update() = 0;
  
  	void on_event();
  
  	virtual void mouseButtonDown(SDL_Event* e) = 0;
  	virtual void mouseButtonUp(SDL_Event* e) = 0;
  	virtual void mouseMotion(SDL_Event* e) = 0;
  };