Plug-In framework using DLLs

// Plug_In_1.h : main header file for the Plug_In_1 DLL
//

#pragma once

#ifndef __AFXWIN_H__
	#error include 'stdafx.h' before including this file for PCH
#endif

#include "resource.h"		// main symbols

// CPlug_In_1App
// See Plug_In_1.cpp for the implementation of this class
//

class CPlug_In_1App : public CWinApp
{
public:
	CPlug_In_1App();
	~CPlug_In_1App();

// Overrides
public:
	virtual BOOL InitInstance();
	virtual int ExitInstance();

// Member variables
private:
	CToolBar *m_pwndToolBar;

public:
	// Used to set the pointer to main app's ToolBar object
	void SetToolBarPointer(CToolBar *pwndToolBar);
	// Used to add button to main app's toolbar
	void AddButtonToToolBar();
	// Used to remove button from main app's toolbar
	void RemoveButtonFromToolBar();
	// Used to call OnCmdMsg method of the App object
	void SendCmdMsgToPlugIn(UINT nID, int nCode, void* pExtra, AFX_CMDHANDLERINFO* pHandlerInfo);

public:
	// Used by main app to get info about the button added by this DLL
	UINT GetToolBarButtonInfo(void);
	// Used to get the handle to the icon or the Plug-In
	HICON* GetPlugInIcon(void);
    DECLARE_MESSAGE_MAP()
	// Used to handle command messages sent by main app
	virtual BOOL OnCmdMsg(UINT nID, int nCode, void* pExtra, AFX_CMDHANDLERINFO* pHandlerInfo);
};