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After reading iczellion's tutorial on dialog boxes I still can't
work out why this dosen't work. In this program the dialog procedure
is never called and DialogBoxParam returns -1 (error) but GetLastError
returns 0 wich is ERROR_SUCESS.

rsrc.rc

#define DS_MODALFRAME	0080h

#define WS_POPUP	80000000h

#define WS_VISIBLE	10000000h

#define WS_CAPTION	0C00000h

#define WS_CLIPSIBLINGS 4000000h

#define IDCANCEL        2



TestDialog DIALOG 6, 18, 231, 79

STYLE DS_MODALFRAME | WS_POPUP | WS_VISIBLE | WS_CAPTION

CAPTION "Test Dialog"

FONT 8, "MS Sans Serif"

BEGIN

    PUSHBUTTON      "Cancel", IDCANCEL, 185, 59, 40, 14

    LTEXT           "Test", 501, 6, 24, 83, 12

END

test.asm

.386

.model flat,stdcall

option casemap:none

include \masm32\include\windows.inc

include \masm32\include\user32.inc

include \masm32\include\kernel32.inc



includelib \masm32\lib\user32.lib

includelib \masm32\lib\kernel32.lib



WinMain proto :DWORD,:DWORD,:DWORD,:DWORD

DlgProc proto :DWORD, :DWORD, :DWORD, :DWORD



DS_MODALFRAME EQU	0080h

WS_POPUP EQU	80000000h

WS_VISIBLE EQU	10000000h

WS_CAPTION	EQU 0C00000h

WS_CLIPSIBLINGS EQU 4000000h

IDCANCEL EQU       2







.data

DlgName db "TestDialog",0

formatstring db "%X",0

.data?

hInstance HINSTANCE ?

Buffer db 10 dup(?)

.code

start:

      invoke GetModuleHandle, NULL

	mov    hInstance,eax

       invoke DialogBoxParam, hInstance, offset DlgName,NULL,offset DlgProc,NULL

      .if eax==-1

          invoke GetLastError

          invoke wsprintf, addr Buffer, addr formatstring, eax

          invoke MessageBox, NULL, addr Buffer, NULL, MB_OK

      .endif

      invoke ExitProcess,eax



DlgProc proc hWnd:HWND, uMsg:UINT, wParam:WPARAM, lParam:LPARAM

       .IF uMsg==WM_INITDIALOG

            mov eax, TRUE

            ret

       .ELSE

		mov eax,FALSE

		ret

	.ENDIF

DlgProc endp

end start

No the dialog is never displayed and I put a MessageBox ast the start of the dialog proc to show when it is called but it isn't, DialogBoxParam returns imediatly. I tried with a message loop but still the same.

I decompiled the resulting .exe file and found that the correct resource was in it. This has been buggin me for a while now I am just missing something so simple

I had the same type of thing happen to me alot when I first started coding dialogs... from what I remember the problem was how you let windows know you processed a message... from the code above it doesn't look like your ending your DlgProc properly...

try this... (untested)

DlgProc proc hWnd:HWND, uMsg:UINT, wParam:WPARAM, lParam:LPARAM

  .IF uMsg==WM_INITDIALOG

    mov eax, TRUE

    ret

  .ELSE

    mov eax,FALSE

    ret

  .ENDIF





  mov eax, TRUE

  ret





DlgProc endp

Hope that helps
JamesE


ahh CodeLover, ya beat me to it :)

many thanks japheth
havn't tested yet but that looks like it's going to work (or at least find out if the resource is being loaded)

Hi bomb01,

Your right actually, there is no point in adding that code me and CodeLover just mentioned as kudos has placed it after the code that handles the message. But to make the code a little easier to read and prevent typing redundant code, we normally have the

mov eax, TRUE

ret

at the end of the proc, that way you don't have to keep typing it over and over as once the .if statement is processed (provided it doesn't go through .else) the execution will fall through.

Your question actually reminded me what I had problems with... it wasn't this ret thing, I think it's the way he has used a string to name his dialog resource.

Kudos, you might want to try this:
rsrc.rc

#define DS_MODALFRAME	0080h

#define WS_POPUP	80000000h

#define WS_VISIBLE	10000000h

#define WS_CAPTION	0C00000h

#define WS_CLIPSIBLINGS 4000000h

#define IDCANCEL        2

#define IDD_TESTDIALOG       1000



IDD_TESTDIALOG DIALOG 6, 18, 231, 79

STYLE DS_MODALFRAME | WS_POPUP | WS_VISIBLE | WS_CAPTION

CAPTION "Test Dialog"

FONT 8, "MS Sans Serif"

BEGIN

    PUSHBUTTON      "Cancel", IDCANCEL, 185, 59, 40, 14

    LTEXT           "Test", 501, 6, 24, 83, 12

END

then...

.386

.model flat,stdcall

option casemap:none

include \masm32\include\windows.inc

include \masm32\include\user32.inc

include \masm32\include\kernel32.inc



includelib \masm32\lib\user32.lib

includelib \masm32\lib\kernel32.lib



WinMain proto :DWORD,:DWORD,:DWORD,:DWORD

DlgProc proto :DWORD, :DWORD, :DWORD, :DWORD



DS_MODALFRAME EQU	0080h

WS_POPUP EQU	80000000h

WS_VISIBLE EQU	10000000h

WS_CAPTION	EQU 0C00000h

WS_CLIPSIBLINGS EQU 4000000h

IDCANCEL EQU       2

IDD_TESTDIALOG       1000





.data

formatstring db "%X",0

.data?

hInstance HINSTANCE ?

Buffer db 10 dup(?)

.code

start:

      invoke GetModuleHandle, NULL

	mov    hInstance,eax

       invoke DialogBoxParam, hInstance, IDD_TESTDIALOG, NULL,offset DlgProc,NULL

      .if eax==-1

          invoke GetLastError

          invoke wsprintf, addr Buffer, addr formatstring, eax

          invoke MessageBox, NULL, addr Buffer, NULL, MB_OK

      .endif

      invoke ExitProcess,eax



DlgProc proc hWnd:HWND, uMsg:UINT, wParam:WPARAM, lParam:LPARAM

       .IF uMsg==WM_INITDIALOG



       .ELSE

		mov eax,FALSE

		ret

	.ENDIF



       mov eax, TRUE

       ret

DlgProc endp

end start

Or if you don't want to convert you resource name to an equate style like above, you might want to try inclosing TestDialog in brackets like so:

"TestDialog" DIALOG 6, 18, 231, 79

I think the resource compiler might be thinking TestDialog is an equate when without the brackets and not an actual string like you are trying.

Anyways, I think this should clear it up for sure this time. heh
James