GUI design question

class TControlHandlers {   public:        TControlHandlers() : me(0) { }      //! Used to bind this handler class to existing control   TControlHandlers(const char * _bindTo);      virtual ~TControlHandlers() { }   // -------------------------------------------------    //! Called (once) when mouse cursor changes from being over one control to being over second control  virtual void GainFocus() { }    //! Send to control that has lost focus  virtual void LostFocus() { }   // -------------------------------------------------  //! Called when user presess keyboard key, if user handler returns false then this _key will be skipped.  //! Also, when TControl's.Keypressed returns false when SDLK_RETURN was passed, LeftMouseButtonPressed  virtual bool Keypressed(SDLKey _key) { return true; }// -------------------------------------------------  // Called when user has pressed appropriate mouse button  virtual void LeftMouseButtonDown(const TScrPoint & _point) { }  virtual void CenterMouseButtonDown(const TScrPoint & _point) { }  virtual void RightMouseButtonDown(const TScrPoint & _point) { }  // -------------------------------------------------    // called when user has released appropriate mouse button  virtual void LeftMouseButtonUp() { }  virtual void CenterMouseButtonUp() { }  virtual void RightMouseButtonUp() { }   // -------------------------------------------------       // called when user released appropriate mouse button, but called only when it happend over control  virtual void LeftMouseButtonPressed(const TScrPoint & _point) { }  virtual void CenterMouseButtonPressed(const TScrPoint & _point) { }  virtual void RightMouseButtonOPressed(const TScrPoint & _point) { }   // -------------------------------------------------  //! User handler is called when Checkboxes state changes to being 'checked'  virtual void Checked() { }    //! User handler is called when Checkboxes state changes to being 'unchecked'  virtual void Unchecked() { }// -------------------------------------------------  protected:         TControl * me;  };

class MyButton : public TControlHandlers {  public:     MyButton(const char * _bindTo) : TControlHandlers(_bindTo) {}            void LeftMouseButtonPressed() { X(); }   void RightMouseButtonPressed() { Y(); }   void SthElse() { // ... }   void Foo() { // et } };int main() {  ...  GUIEngine.LoadUI("gui.xml"); // controls must already exist  MyButton button1("NewGame.PlayerScreen.Foo");  ... }