Can't create a popup window

Hello guys. I am new to windows programming and i've got a problem. I just can't create a popup window. I have viewed my code thoroughly several times and i have no idea what's wrong.
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#include "stdafx.h"
#include "DIARY3.h"



#define MAX_LOADSTRING 100

// Global Variables:
HINSTANCE hInst;								// current instance
TCHAR szTitle[MAX_LOADSTRING];					// The title bar text
TCHAR szWindowClass[MAX_LOADSTRING];			// the main window class name
TCHAR SecondWindowClassName[MAX_LOADSTRING] = _T("SecondWindowClass");


// Forward declarations of functions included in this code module:
ATOM				MyRegisterClass(HINSTANCE hInstance);
BOOL				InitInstance(HINSTANCE, int);
LRESULT CALLBACK	WndProc(HWND, UINT, WPARAM, LPARAM);
LRESULT CALLBACK    SecWndProc(HWND, UINT, WPARAM, LPARAM);


int APIENTRY _tWinMain(HINSTANCE hInstance,
                     HINSTANCE hPrevInstance,
                     LPTSTR    lpCmdLine,
                     int       nCmdShow)
{
	UNREFERENCED_PARAMETER(hPrevInstance);
	UNREFERENCED_PARAMETER(lpCmdLine);

 	// TODO: Place code here.
	MSG msg;
	HACCEL hAccelTable;

	// Initialize global strings
	LoadString(hInstance, IDS_APP_TITLE, szTitle, MAX_LOADSTRING);
	LoadString(hInstance, IDC_DIARY3, szWindowClass, MAX_LOADSTRING);
	MyRegisterClass(hInstance);

	// Perform application initialization:
	if (!InitInstance (hInstance, nCmdShow))
	{
		return FALSE;
	}

	hAccelTable = LoadAccelerators(hInstance, MAKEINTRESOURCE(IDC_DIARY3));

	// Main message loop:
	while (GetMessage(&msg, NULL, 0, 0))
	{
		if (!TranslateAccelerator(msg.hwnd, hAccelTable, &msg))
		{
			TranslateMessage(&msg);
			DispatchMessage(&msg);
		}
	}

	return (int) msg.wParam;
}



//
//  FUNCTION: MyRegisterClass()
//
//  PURPOSE: Registers the window class.
//
//  COMMENTS:
//
//    This function and its usage are only necessary if you want this code
//    to be compatible with Win32 systems prior to the 'RegisterClassEx'
//    function that was added to Windows 95. It is important to call this function
//    so that the application will get 'well formed' small icons associated
//    with it.
//
ATOM MyRegisterClass(HINSTANCE hInstance)
{
	WNDCLASSEX wcex;

	wcex.cbSize = sizeof(WNDCLASSEX);

	wcex.style			= CS_HREDRAW | CS_VREDRAW;
	wcex.lpfnWndProc	= WndProc;
	wcex.cbClsExtra		= 0;
	wcex.cbWndExtra		= 0;
	wcex.hInstance		= hInstance;
	wcex.hIcon			= LoadIcon(hInstance, MAKEINTRESOURCE(IDI_DIARY3));
	wcex.hCursor		= LoadCursor(NULL, IDC_ARROW);
	wcex.hbrBackground	= (HBRUSH)(COLOR_WINDOW+1);
	wcex.lpszMenuName	= MAKEINTRESOURCE(IDC_DIARY3);
	wcex.lpszClassName	= szWindowClass;
	wcex.hIconSm		= LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_SMALL));

	return RegisterClassEx(&wcex);
}

ATOM RegisterSecondWindowClass()
{
	WNDCLASSEX wc = {0};

	wc.cbSize = sizeof(WNDCLASSEX);
	wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
	wc.hCursor = LoadCursor(NULL,IDC_ARROW);
	wc.hIconSm = LoadIcon(NULL,IDI_APPLICATION);
	wc.hInstance = hInst;
	wc.lpfnWndProc = SecWndProc;
	wc.lpszClassName = SecondWindowClassName;
	wc.style = CS_HREDRAW|CS_VREDRAW;
   
	return RegisterClassEx(&wc);
  
}


//
//   FUNCTION: InitInstance(HINSTANCE, int)
//
//   PURPOSE: Saves instance handle and creates main window
//
//   COMMENTS:
//
//        In this function, we save the instance handle in a global variable and
//        create and display the main program window.
//
BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
{
   HWND hWnd;

   hInst = hInstance; // Store instance handle in our global variable

   hWnd = CreateWindow(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,
      CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, hInstance, NULL);

   if (!hWnd)
   {
      return FALSE;
   }

   ShowWindow(hWnd, nCmdShow);
   UpdateWindow(hWnd);

   return TRUE;
}

//
//  FUNCTION: WndProc(HWND, UINT, WPARAM, LPARAM)
//
//  PURPOSE:  Processes messages for the main window.
//
//  WM_COMMAND	- process the application menu
//  WM_PAINT	- Paint the main window
//  WM_DESTROY	- post a quit message and return
//
//
int sx,sy;



LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
	int wmId, wmEvent;
	PAINTSTRUCT ps;
	HDC hdc;
    Event an_event;
    static HWND SecondWindow;

	switch (message)
	{
	case WM_CREATE:
		
		break;
	case WM_SIZE:
		sx = LOWORD(lParam);
		sy = HIWORD(lParam);
		break;
	case WM_COMMAND:
		wmId    = LOWORD(wParam);
		wmEvent = HIWORD(wParam);
		// Parse the menu selections:
		switch (wmId)
		{
		case ID_WATCH:
			RegisterSecondWindowClass();
			SecondWindow = CreateWindow(SecondWindowClassName,_T("Current events"), WS_SYSMENU|WS_POPUP|WS_VISIBLE| WS_THICKFRAME|WS_CAPTION,sx/2,sy/2,
min(sx,sy),min(sx,sy),hWnd,0,hInst,NULL);
			if (!SecondWindow)
			MessageBox (hWnd,"Can't create window","Error",MB_OK);
			
			break;
		case ID_EXIT:
			DestroyWindow(hWnd);
			break;
		default:
			return DefWindowProc(hWnd, message, wParam, lParam);
		}
		break;
	case WM_PAINT:
		hdc = BeginPaint(hWnd, &ps);
		// TODO: Add any drawing code here...

		EndPaint(hWnd, &ps);
		break;
	case WM_DESTROY:
		PostQuitMessage(0);
		break;
	default:
		return DefWindowProc(hWnd, message, wParam, lParam);
	}
	return 0;
}

LRESULT CALLBACK SecWndProc (HWND hWnd,UINT message,WPARAM wParam,LPARAM lParam)
{
    PAINTSTRUCT ps;
	HDC hdc;

   switch (message)
   {
   case WM_CLOSE:
	   DestroyWindow(hWnd);
	   break;
   case WM_SIZE:
	   break;
   case WM_PAINT:
	   hdc = BeginPaint(hWnd,&ps);
	   EndPaint(hWnd,&ps);
	   break;
   }
   return 0;
}

I did everything necessary. I registered a class, then used CreateWindow function. What did i miss? ID_WATCH is working for sure cause i'm getting "Can't create window" message. Can you please explain me what's going on?
Use GetLastError() to find out what's wrong:

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//This typedef is needed somewhere before the actual code shown after it.
typedef std::basic_string<TCHAR> tstring;

...

if (!SecondWindow)
{
    DWORD dwError = GetLastError();
    LPTSTR szMsg = NULL;
    FormatMessage(
        FORMAT_MESSSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS
        , NULL
        , dwError
        , 0
        , (LPTSTR)&szMsg
        , 0
        , NULL
        );
    //Create an STL string object for easier string management.
    tstring strErrorMsg = szMsg;
    //Unmanaged buffer no longer needed, so free it.
    LocalFree(szMsg);


That should give you the error message and error code.

BTW, you could put the above in an inlined function so it is easier to call, or better yet, create a Win32Exception class that inherits from std::exception and that takes a DWORD in its constructor.
Last edited on
Thank you very much, webJose
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