DialogBox() Always returns -1

Hello.

Sorry, I realize there are millions of threads about dialog boxes here, but I've searched through them loads and haven't yet found an answer to my problem. Like most noobs here, I'm using the tutorial at www.winprog.net. Anyways, heres my code:

Windows.cpp

Code:

#include <windows.h>

#define IDC_STATIC '-1'

const char g_szClassName[] = "WindowClass";
HWND hWindowHandle;

////////////////////////////////////////////////////////////////////////////////
////////////////////////////// Control1 procedure //////////////////////////////
////////////////////////////////////////////////////////////////////////////////

BOOL CALLBACK Control1DlgProc(HWND hwnd, UINT Message, WPARAM wParam, LPARAM lParam)
{
    switch(Message)
    {
        case WM_INITDIALOG:

            return TRUE;
        
            case WM_COMMAND:
            
                switch(LOWORD(wParam))
                {
                    case IDOK:
                        EndDialog(hwnd, IDOK);
                        break;
                    
                    case IDCANCEL:
                        EndDialog(hwnd, IDCANCEL);
                        break;
                }
        
            break;
        
        default:
            return FALSE;
    }
    
    return TRUE;
}

////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////

// Step 4: the Window Procedure

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
    switch(msg)
    {
        case WM_CREATE:
            
            int Control1_Result;
            Control1_Result = DialogBox(GetModuleHandle(NULL), MAKEINTRESOURCE(101), hwnd, Control1DlgProc);
            
            if(Control1_Result == -1)
            {
                MessageBox(hWindowHandle, "Dialog failed!", "Error", MB_OK | MB_ICONINFORMATION);
            }    
            
            break;
        
        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;
    MSG MainMessage;

    //Step 1: Registering the Window Class
    
    wc.cbSize        = sizeof(WNDCLASSEX);
    wc.style         = 0;
    wc.lpfnWndProc   = WndProc;
    wc.cbClsExtra    = 0;
    wc.cbWndExtra    = 0;
    wc.hInstance     = hInstance;
    wc.hIcon         = LoadIcon(NULL, IDI_APPLICATION);
    wc.hCursor       = LoadCursor(NULL, IDC_ARROW);
    wc.hbrBackground = (HBRUSH)(COLOR_WINDOW + 11);
    wc.lpszMenuName  = NULL;
    wc.lpszClassName = g_szClassName;
    wc.hIconSm       = LoadIcon(NULL, IDI_APPLICATION);

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

    // Step 2: Creating the Window
    
    hWindowHandle = CreateWindowEx(
        WS_EX_CLIENTEDGE | WS_EX_TOPMOST,
        g_szClassName,
        "Windows Application",
        WS_DLGFRAME,
        120, 120, 240, 240,
        NULL, NULL, hInstance, NULL);

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

    ShowWindow(hWindowHandle, nCmdShow);
    UpdateWindow(hWindowHandle);

    // Step 3: The Message Loop
    
    while(GetMessage(&MainMessage, NULL, 0, 0) > 0)
    {
        TranslateMessage(&MainMessage);
        DispatchMessage(&MainMessage);
    }
    
    return MainMessage.wParam;
}

Control1.rc

Code:

#include <windows.h>

#if !defined IDC_STATIC
#define IDC_STATIC -1
#endif

IDD_Control1 DIALOG DISCARDABLE  120, 120, 240, 65

STYLE DS_MODALFRAME | WS_POPUP | WS_CAPTION | WS_SYSMENU
CAPTION "Windows Application"
FONT 8, "MS Sans Serif"

BEGIN
    
    DEFPUSHBUTTON   "&Yes",IDYES,174,18,50,14
    PUSHBUTTON      "&No",IDNO,174,35,50,14
    GROUPBOX        "Login", IDC_STATIC,7,7,225,52
    CTEXT           "Do you wish to login to Windows Application?", IDC_STATIC,16,18,144,33
    
END

Control1.h

Code:

#define IDD_CONTROL1 101

My problem is that the dialog simply dosen't show. Hence the title.
Any suggestions?
Cheers!

It could be a copying error, but it appears that you haven't #included Control1.h at the top of Control1.rc. Also, IDD_CONTROL1 is different to IDD_Control1.

The general style is to include the resource header (Control1.h) in both the resource file and the code file and then use the constants rather than using numbers directly.

Thanks for the reply.

Ok so I changed it to:

Code:

Control1_Result = DialogBox(GetModuleHandle(NULL), MAKEINTRESOURCE(IDD_Control1), hwnd, Control1DlgProc);

But I get: 55 C:\Dev-Cpp\Programs\Test\Windows.cpp `IDD_Control1' undeclared (first use this function)

Even though I changed Control1.h to: #define IDD_Control1 101

What's going on there? It says it is undefined when it isn't. Wierd.
Thanks for the help and any more you can lend.

To reiterate anonytmouse's solution(and add a little):

In Windows.cpp, replace:

Code:

#include <windows.h>

#define IDC_STATIC '-1'

with

Code:

#include <windows.h>
#include "Control1.h"

In Control1.rc, replace

Code:

#include <windows.h>

#if !defined IDC_STATIC
#define IDC_STATIC -1
#endif

with

Code:

#include <afxres.h>
#include "Control1.h"

This should ensure all the proper definitions are where they are supposed to be, as described by anonytmouse.

Ah. All is now clear. Except one thing: What is: afxres.h?

But it's working now!
Thanks for all your help.

>>What is: afxres.h?<<

It was added to MinGW a few years ago to increase compatibility with existing msvc specific code that used resources; all it does is #include windows.h and #define IDC_STATIC (take a peek yourself in the 'include' directory of your dev-cpp or mingw installation, if you're interested).