Window not showing

[dumb_terminal]

hello all, this is my first post.so forgive me i am at the wrong forum. I have coded the following so far, compiled and inked successfully but can't see the window. Whats wrong ?? plz somebody help
Here is the code

Code Select Expand


.386
.model flat, stdcall
option casemap:none

include d:\masm32\include\windows.inc
include d:\masm32\include\kernel32.inc
include d:\masm32\include\user32.inc
include d:\masm32\include\gdi32.inc

includelib d:\masm32\lib\kernel32.lib
includelib d:\masm32\lib\user32.lib
includelib d:\masm32\lib\gdi32.lib
includelib d:\masm32\lib\import32.lib

WinMain proto :DWORD, :DWORD, :DWORD, :DWORD
;WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR cmdLine, int nShowCmd)

.data
    wClassName db  "SimpleWindowClassA", 0
    wWinName   db  "My First Window using Assembly", 0
   
.data?
    hInstance HINSTANCE ?
    cmdLine   LPSTR     ?
   
.code
start:
    ; getting instace of our program
    invoke GetModuleHandle, NULL
    mov hInstance, eax

    ; get command line
    ;invoke GetCommandLine
    ;mov cmdLine, eax

    ; call WinMain
    invoke WinMain, hInstance, NULL, NULL, SW_SHOWDEFAULT
   
    ; quit if we return from win main
    invoke ExitProcess, NULL


    ;the WinMain
    WinMain proc hInst:HINSTANCE, hPrevInst:HINSTANCE, CommandLine:LPSTR, nShowCmd:DWORD
        ; take note dfining a local variable
        ; the WindowClass structure
        LOCAL wc  :WNDCLASSEX
        LOCAL msg : MSG
        LOCAL hWnd: HWND

        ; filling up wc
        mov wc.cbSize, SIZEOF WNDCLASSEX
        mov wc.style, CS_HREDRAW or CS_VREDRAW
        mov wc.lpfnWndProc, offset WndProc
        mov wc.cbClsExtra, NULL
        mov wc.cbWndExtra, NULL
        push hInstance
        pop wc.hInstance
        mov wc.hbrBackground, COLOR_WINDOW + 1
        mov wc.lpszMenuName, NULL
        mov wc.lpszClassName, offset wClassName
        invoke LoadIcon, NULL, IDI_APPLICATION
        mov wc.hIcon, eax
        mov wc.hIconSm, eax
        Invoke LoadCursor, NULL, IDC_ARROW
        mov wc.hCursor, eax

        ; now register class
        Invoke RegisterClassEx, addr wc

        ;create it actully
        invoke CreateWindowEx, NULL, addr wClassName, addr wWinName, WS_OVERLAPPEDWINDOW,   CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInst, NULL
        mov hWnd, eax

        ; show window
        invoke ShowWindow, hWnd, nShowCmd

        ; update it
        invoke UpdateWindow, hWnd

        ; notice MASM's easier than C Macro WHILE loop
        .WHILE TRUE
            invoke GetMessage, addr msg, NULL, 0, 0
            .BREAK .IF(!eax)
            invoke TranslateMessage, addr msg
            invoke DispatchMessage, addr msg
        .ENDW
        mov eax, msg.wParam
        ret
    WinMain endp

    WndProc proc hwnd: HWND, uMsg: UINT, wParam: WPARAM, lParam: LPARAM
        .IF uMsg == WM_DESTROY
            invoke PostQuitMessage, NULL
        .ELSE
            invoke DefWindowProc, hwnd, uMsg, wParam, lParam
        .ENDIF
        xor eax, eax
        ret
    WndProc endp
end start

and using following commands for assembling and linking

Code Select Expand


ml /c /coff /Cp ice3.asm
link /SUBSYSTEM:WINDOWS /LIBPATH:d:\masm32\lib ice3.obj
ice3.exe


[bomz]

I am not see where error

http://www.mbuilder.jino-net.ru/en/index.html

[MichaelW]

The window is not showing because your call to CreateWindowEx is failing. When your window procedure calls DefWindowProc it normally should return whatever DefWindowProc returns.

Code Select Expand


WndProc proc hwnd: HWND, uMsg: UINT, wParam: WPARAM, lParam: LPARAM
    .IF uMsg == WM_DESTROY
        invoke PostQuitMessage, NULL
    .ELSE
        invoke DefWindowProc, hwnd, uMsg, wParam, lParam
        ret  ;<<<<<<
    .ENDIF
    xor eax, eax
    ret
WndProc endp


[hutch--]

terminal,

Tell us what OS version you are running, I am getting very strange error messages right at the "start:" label and onwards. If you are not committed to this particular bare window, we can easily give you a reliable one that does work.

[dumb_terminal]

 @MicahelW: Salute Sir. That was awsome sir, just added the ret, and it showed....!!! well masm is fun, no more fooling around just to write a nested if. But it wud be gr8 if u explain a litttle bit more, i am a n00b right now.

@hutch-- : well sir Windows XP (yeah a bit backdated).

[MichaelW]

The problem is with the handling of the WM_NCCREATE message.

"If an application processes this message, it should return TRUE to continue creation of the window. If the application returns FALSE, the CreateWindow or CreateWindowEx function will return a NULL handle."

Since your window procedure does not handle WM_NCCREATE directly it gets passed to the default window procedure. The default window procedure returns TRUE, but your .IF block then falls through and the return value gets overwritten with NULL.

[dumb_terminal]

The problem is with the handling of the WM_NCCREATE message.

"If an application processes this message, it should return TRUE to continue creation of the window. If the application returns FALSE, the CreateWindow or CreateWindowEx function will return a NULL handle."

Since your window procedure does not handle WM_NCCREATE directly it gets passed to the default window procedure. The default window procedure returns TRUE, but your .IF block then falls through and the return value gets overwritten with NULL.

Oh i see, thank u Sir.  :clap: