Не открывается GUI WinApi

Question

#include <Windows.h>

LRESULT CALLBACK SoftwareMainProcedure(HWND hWnd, UINT msg, WPARAM wp, LPARAM lp);
WNDCLASS NewWindowClass(HBRUSH BGColor, HCURSOR Cursor, HINSTANCE hInst, HICON Icon, LPCWSTR Name, WNDPROC Procedure);

int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, LPSTR args, int ncmdshow) {
    HWND hWnd;
    WNDCLASS SoftwareMainClass = NewWindowClass((HBRUSH)COLOR_WINDOW, LoadCursor(NULL, IDC_ARROW), hInst, LoadIcon(NULL, IDI_QUESTION), L"MainWndClass", SoftwareMainProcedure);
    if (!RegisterClassW(&SoftwareMainClass)) { return -1; }
    MSG SoftwareMainMessage = { 0 };
    hWnd = CreateWindow(L"MainWndClass", L"First c++ window", WS_OVERLAPPEDWINDOW | WS_VISIBLE, 100, 100, 500, 250, NULL, NULL, NULL, NULL);
    while (GetMessage(&SoftwareMainMessage, NULL, NULL, NULL)) {
        TranslateMessage(&SoftwareMainMessage);
        DispatchMessage(&SoftwareMainMessage);
    }
    return 0;
}

WNDCLASS NewWindowClass(HBRUSH BGColor, HCURSOR Cursor, HINSTANCE hInst, HICON Icon, LPCWSTR Name, WNDPROC Procedure) {
    WNDCLASS NWC = { 0 };
    NWC.hCursor = Cursor;
    NWC.hIcon = Icon;
    NWC.hInstance = hInst;
    NWC.lpszClassName = Name;
    NWC.hbrBackground = BGColor;
    NWC.lpfnWndProc = Procedure;
    return NWC;
}
LRESULT CALLBACK SoftwareMainProcedure(HWND hWnd, UINT msg, WPARAM wp, LPARAM lp) {
    switch (msg)
    {
    case WM_CREATE:
        break;
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
    default: return DefWindowProc(hWnd, msg, wp, wp);
    }
}

Не открывается GUI окошко, а процесс программы весит в диспетчере задач.

Answer 1

Опечатка: должно быть

default: return DefWindowProc(hWnd, msg, wp, lp);

вместо

default: return DefWindowProc(hWnd, msg, wp, wp);

Плюс обработчик WM_CREATE должен возвращать 0.

Answer 2

Думаю красивее чем разработчики документации от Майкрософт не смогут ответить на все вопросы связанные с созданием окна.

И так что нам говорят Microsoft Learn по поводу создания окна.

https://learn.microsoft.com/en-us/windows/win32/learnwin32/your-first-windows-program

#ifndef UNICODE
#define UNICODE
#endif 

#include <windows.h>

LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam);

int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PWSTR pCmdLine, int nCmdShow)
{
    // Register the window class.
    const wchar_t CLASS_NAME[]  = L"Sample Window Class";
    
    WNDCLASS wc = { };

    wc.lpfnWndProc   = WindowProc;
    wc.hInstance     = hInstance;
    wc.lpszClassName = CLASS_NAME;

    RegisterClass(&wc);

    // Create the window.

    HWND hwnd = CreateWindowEx(
        0,                              // Optional window styles.
        CLASS_NAME,                     // Window class
        L"Learn to Program Windows",    // Window text
        WS_OVERLAPPEDWINDOW,            // Window style

        // Size and position
        CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,

        NULL,       // Parent window    
        NULL,       // Menu
        hInstance,  // Instance handle
        NULL        // Additional application data
        );

    if (hwnd == NULL)
    {
        return 0;
    }

    ShowWindow(hwnd, nCmdShow);

    // Run the message loop.

    MSG msg = { };
    while (GetMessage(&msg, NULL, 0, 0) > 0)
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }

    return 0;
}

LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    switch (uMsg)
    {
    case WM_DESTROY:
        PostQuitMessage(0);
        return 0;

    case WM_PAINT:
        {
            PAINTSTRUCT ps;
            HDC hdc = BeginPaint(hwnd, &ps);

            // All painting occurs here, between BeginPaint and EndPaint.

            FillRect(hdc, &ps.rcPaint, (HBRUSH) (COLOR_WINDOW+1));

            EndPaint(hwnd, &ps);
        }
        return 0;

    }
    return DefWindowProc(hwnd, uMsg, wParam, lParam);
}

БЛОГ НА HUSL

Не открывается GUI WinApi

Ответы (2 шт):