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Window Registration fails

pcultras (55)
Hello, I'm just learning windows programming and wanted to make a simple window with a top bar menu, but for some strange reason the registration of the window fails... Can someone tell me what's wrong? 

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#include <windows.h>

#define ID_FILE_EXIT 9001
#define ID_STUFF_GO 9002

wchar_t g_szClassName[] = L"myWindowClass";

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
	switch(msg)
    {
        case WM_CREATE:
    {
        HMENU hMenu, hSubMenu;
        HICON hIcon, hIconSm;

        hMenu = CreateMenu();

        hSubMenu = CreatePopupMenu();
        AppendMenu(hSubMenu, MF_STRING, ID_FILE_EXIT, L"E&xit");
        AppendMenu(hMenu, MF_STRING | MF_POPUP, (UINT)hSubMenu, L"&File");

        hSubMenu = CreatePopupMenu();
        AppendMenu(hSubMenu, MF_STRING, ID_STUFF_GO, L"&Go");
        AppendMenu(hMenu, MF_STRING | MF_POPUP, (UINT)hSubMenu, L"&Stuff");

        SetMenu(hwnd, hMenu);

        hIcon = (HICON)LoadImage(NULL, L"menu_two.ico", IMAGE_ICON, 32, 32, LR_LOADFROMFILE);
        if(hIcon)
            SendMessage(hwnd, WM_SETICON, ICON_BIG, (LPARAM)hIcon);
        else
            MessageBox(hwnd, L"Could not load large icon!", L"Error", MB_OK | MB_ICONERROR);

        hIconSm = (HICON)LoadImage(NULL, L"menu_two.ico", IMAGE_ICON, 16, 16, LR_LOADFROMFILE);
        if(hIconSm)
            SendMessage(hwnd, WM_SETICON, ICON_SMALL, (LPARAM)hIconSm);
        else
            MessageBox(hwnd, L"Could not load small icon!", L"Error", MB_OK | MB_ICONERROR);
    }
		case WM_CLOSE:
            DestroyWindow(hwnd);
        break;
        case WM_DESTROY:
            PostQuitMessage(0);
        break;
        default:
            return DefWindowProc(hwnd, msg, wParam, lParam);
    }
    return 0;
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
    LPSTR lpCmdLine, int nCmdShow)
{
    WNDCLASSEX wc;
    HWND hwnd;
    MSG Msg;

    wc.cbSize        = sizeof(WNDCLASSEX);
    wc.style         = 0;
    wc.lpfnWndProc   = WndProc;
    wc.cbClsExtra    = 0;
    wc.cbWndExtra    = 0;
    wc.hInstance     = hInstance;
	wc.hIcon         = LoadIcon(NULL, MAKEINTRESOURCE(IDI_APPLICATION));
	wc.hIconSm       = LoadIcon(NULL, MAKEINTRESOURCE(IDI_APPLICATION));
    wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
    wc.lpszClassName = g_szClassName;
	wc.lpszMenuName  = NULL;

    if(!RegisterClassEx(&wc))
    {
        MessageBox(NULL, L"Window Registration Failed!", L"Error!",
            MB_ICONEXCLAMATION | MB_OK);
        return 0;
    }

    hwnd = CreateWindowEx(
        WS_EX_CLIENTEDGE,
        g_szClassName,
        L"The title of my window",
        WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT, CW_USEDEFAULT, 240, 120,
        NULL, NULL, hInstance, NULL);

    if(hwnd == NULL)
    {
        MessageBox(NULL, L"Window Creation Failed!", L"Error!",
            MB_ICONEXCLAMATION | MB_OK);
        return 0;
    }

    ShowWindow(hwnd, nCmdShow);
    UpdateWindow(hwnd);

    while(GetMessage(&Msg, NULL, 0, 0) > 0)
    {
        TranslateMessage(&Msg);
        DispatchMessage(&Msg);
    }
    return Msg.wParam;
}
kaije (34)
Make sure you fill in all the parameteres of WNDCLASSEX structure, you've missed out hCursor and also your loading of icons shouldn't use MAKEINTRESOURCE, they should be:

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wc.hIcon         = LoadIcon(NULL,  IDI_APPLICATION);
wc.hIconSm    = LoadIcon(NULL, IDI_APPLICATION);
wc.hCursor     = LoadCursor(NULL, IDC_ARROW);


And to make sure you can zero out the structure when you initilize it:

 
 
WNDCLASSEX wc = {0};


then you don't have to type of the ones which are NULL or 0

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typedef struct tagWNDCLASSEX {
  UINT      cbSize;
  UINT      style;
  WNDPROC   lpfnWndProc;
  int       cbClsExtra;
  int       cbWndExtra;
  HINSTANCE hInstance;
  HICON     hIcon;
  HCURSOR   hCursor;
  HBRUSH    hbrBackground;
  LPCTSTR   lpszMenuName;
  LPCTSTR   lpszClassName;
  HICON     hIconSm;
} WNDCLASSEX, *PWNDCLASSEX;

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