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So, I am continuing to work through a tutorial and I have run into another 'undeclared identifier' error. I have checked that the definition exists in resource.h, but I still get the error. Again, it is a short tutorial, so here is the code:
//MFC5.CPP - MFC Tutorial Part 5 from
#include <afxwin.h>
#include "resource.h"
#include "newdialog.h"

class MFC_Tutorial_Window :public CFrameWnd
	CMenu menu1;
        Create(NULL,_T("MFC Tutorial Part 5 CoderSource Dialog"));
    void OnClickDialogNew();
BEGIN_MESSAGE_MAP( MFC_Tutorial_Window, CFrameWnd)
void MFC_Tutorial_Window::OnClickDialogNew()
    newdialog dlg;
class MyApp :public CWinApp

The compiler gives me the following error (it is the only error):
newdialog.h(15): error C2065: 'ID_MYDIALOG' : undeclared identifier

The error message brings me to enum { IDD = ID_MYDIALOG }; which is line 15 from the following code.

<pre lang="cs">#pragma once

// newdialog dialog

class newdialog : public CDialog

    newdialog(CWnd* pParent = NULL);   // standard constructor
    virtual ~newdialog();

// Dialog Data
    enum { IDD = ID_MYDIALOG };

    virtual void DoDataExchange(CDataExchange* pDX);    // DDX/DDV support


Any suggestion on where I should look? Also, if there is a recommendation for a tutorial not written for VC6, but for VS2010 it would make things easier. However, I have been learning by my mistakes....

Ok, so I was able to fix the compiler issue by including resource.h (per advice) in the newdialog class...but now the dialog box doesn't show! I included a menu resource, but clicking on 'New' doesn't cause the dialog box to appear.
Updated 14-Jun-11 19:28pm
Resmi Anna 15-Jun-11 0:07am    
Go to your resource view. check the dialog id of newly created dialog.
Probably it will be something other than 'ID_MYDIALOG'. Pls change it to 'ID_MYDIALOG'.
AndrewG1231 15-Jun-11 0:12am    
The ID and resource match...oddly enough, the problem is not identified in MFC5.cpp but the compiler alerts me when it reaches it in 'newdialog.h' above.
Resmi Anna 15-Jun-11 0:17am    
what is the name of the file that you have given for this dialog class?
also is it needed to include #include<afxwin.h>??
i dont think. you are doing evrything via classwizard rt?
AndrewG1231 15-Jun-11 0:21am    
Yes, the class was added with the class wizard and the class name is 'newdialog'. The afxwin.h is required for CDialog as I understand MSDN.
Resmi Anna 15-Jun-11 0:40am    
#include "resource.h" in your newdialog.h file

1 solution

as written in a comment you need to

#include "resource.h"

in the header, and the ID_MYDIALOG must be defined there
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