Re: window from win32 dll

From:

kalpesh <kalpeshgedia@gmail.com>

Newsgroups:

microsoft.public.vc.mfc

Date:

Tue, 2 Sep 2008 03:32:48 -0700 (PDT)

Message-ID:

<d90af2f8-cd68-4bad-939d-fbee1b682fba@s9g2000prg.googlegroups.com>

On Sep 2, 9:19 am, keralaf...@gmail.com wrote:

thanks..actually i just cut and paste this code form Direct3D
tutorials,i need direct3D window(for displaying Direct3d,directx9
tutorials i used))..
changes i made was calling in dll,implicitly linked(some one calls
static linking i believe its load when program execute,so dll
instance
might be going wrong, i think so. ).i mentioned earlier Hinsiance i
am storing in dll main and using it...
i couldn't understand what is the problem using class..so many guys
do same thing.window creation function and msgproc inside one class
and using it.i tried outside class also with diffrent parameters.i
belive it would be hinstnace problem.

CreateWindow not returning window handle.that is the problem..last
error zero.

Please use function "GetLastError()" it will return you the exact
error code why window is not created.

Here i write one example for creating window please go through it.

#include <windows.h>

// Global variable

HINSTANCE hinst;

// Function prototypes.

int WINAPI WinMain(HINSTANCE, HINSTANCE, LPSTR, int);
InitApplication(HINSTANCE);
InitInstance(HINSTANCE, int);
LRESULT CALLBACK MainWndProc(HWND, UINT, WPARAM, LPARAM);

// Application entry point.

int WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance,
    LPSTR lpCmdLine, int nCmdShow)
{
    MSG msg;

    if (!InitApplication(hinstance))
        return FALSE;

    if (!InitInstance(hinstance, nCmdShow))
        return FALSE;

    BOOL fGotMessage;
    while ((fGotMessage = GetMessage(&msg, (HWND) NULL, 0, 0)) != 0 &&
fGotMessage != -1)
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    return msg.wParam;
        UNREFERENCED_PARAMETER(lpCmdLine);
}

BOOL InitApplication(HINSTANCE hinstance)
{
    WNDCLASSEX wcx;

    // Fill in the window class structure with parameters
    // that describe the main window.

    wcx.cbSize = sizeof(wcx); // size of structure
    wcx.style = CS_HREDRAW |
        CS_VREDRAW; // redraw if size changes
    wcx.lpfnWndProc = MainWndProc; // points to window procedure
    wcx.cbClsExtra = 0; // no extra class memory
    wcx.cbWndExtra = 0; // no extra window memory
    wcx.hInstance = hinstance; // handle to instance
    wcx.hIcon = LoadIcon(NULL,
        IDI_APPLICATION); // predefined app. icon
    wcx.hCursor = LoadCursor(NULL,
        IDC_ARROW); // predefined arrow
    wcx.hbrBackground = GetStockObject(
        WHITE_BRUSH); // white background brush
    wcx.lpszMenuName = "MainMenu"; // name of menu resource
    wcx.lpszClassName = "MainWClass"; // name of window class
    wcx.hIconSm = LoadImage(hinstance, // small class icon
        MAKEINTRESOURCE(5),
        IMAGE_ICON,
        GetSystemMetrics(SM_CXSMICON),
        GetSystemMetrics(SM_CYSMICON),
        LR_DEFAULTCOLOR);

    // Register the window class.

    return RegisterClassEx(&wcx);
}

BOOL InitInstance(HINSTANCE hinstance, int nCmdShow)
{
    HWND hwnd;

    // Save the application-instance handle.

    hinst = hinstance;

    // Create the main window.

    hwnd = CreateWindow(
        "MainWClass", // name of window class
        "Sample", // title-bar string
        WS_OVERLAPPEDWINDOW, // top-level window
        CW_USEDEFAULT, // default horizontal position
        CW_USEDEFAULT, // default vertical position
        CW_USEDEFAULT, // default width
        CW_USEDEFAULT, // default height
        (HWND) NULL, // no owner window
        (HMENU) NULL, // use class menu
        hinstance, // handle to application instance
        (LPVOID) NULL); // no window-creation data

    if (!hwnd)
        return FALSE;

    // Show the window and send a WM_PAINT message to the window
    // procedure.

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

}