I have difficulties creating a dialog box - winapi

Question

I really do not know what i am doing wrong.
I would like to create a dialogbox.
It is just does not show.
Declaration
BOOL CALLBACK NewDlgProc(HWND main, UINT msg, WPARAM wParam, LPARAM lParam);
Diagproc:
BOOL CALLBACK NewDlgProc(HWND main, UINT msg, WPARAM wParam, LPARAM lParam)
{
switch(msg)
{
case WM_INITDIALOG:
return TRUE;
case WM_COMMAND:
{
}
break;
default:
return FALSE;
}
return TRUE;
}
In windproc wm_command:
case ID_MENU_NEW:
{
int NewDlg = DialogBox(GetModuleHandle(NULL),
MAKEINTRESOURCE(ID_DIALOG_NEW), main, NewDlgProc);
if(NewDlg == 0)
MessageBox(main, "Cannot create dialogbox", "Error", MB_OK | MB_ICONERROR);
}
break;
resource.h:
#define ID_DIALOG_NEW 201
dlg.rc
#include <windows.h>
#include "resource.h"
ID_DIALOG_NEW DIALOG DISCARDABLE 100,100, 100,100
STYLE DS_MODALFRAME | WS_VISIBLE | WS_CHILD | WS_CAPTION
CAPTION "Add new"
FONT 8, "Ms Sans Serif"
BEGIN
END

Answer 1

A dialog can have an owner or be unowned, but it cannot have a parent. Consequently, you cannot have the WS_CHILD window style for a dialog. Replace that with WS_POPUP, and everyone will be happy.
Relevant quote from the MSDN (About Dialog Boxes : Modal Dialog Boxes):
An application must not create a modal dialog box having the WS_CHILD style.

Answer 2

How come in your dialog procedure you are not calling DefDlgProc() for the messages you are not handling?
BOOL CALLBACK NewDlgProc(HWND main, UINT msg, WPARAM wParam, LPARAM lParam)
{
switch(msg)
{
case WM_INITDIALOG:
return TRUE;
case WM_COMMAND:
{
}
break;
default:
return DefDlgProc(main, msg, wParam, lParam); // need default processing!!!!!!!!!!
}
return TRUE;
}