--- a/MCEPeriodicTable.h
+++ b/MCEPeriodicTable.h
@@ -55,6 +55,8 @@
 	afx_msg void OnRButtonUp(UINT nFlags, CPoint point);
 	//}}AFX_MSG
 	DECLARE_MESSAGE_MAP()
+public:
+    afx_msg void OnBnClickedOk();
 };
 
 //{{AFX_INSERT_LOCATION}}