C++ Win32api, creating a dialog box without resource

Question

I'm new to win32api programming. I would like to know how to create a dialog box within a non-gui program (without any resource created).

I've seen some examples with that CreateIndirect function. Is it the best method? Any other way?

Thanks!

Answer 1

You would use DialogBoxIndirectParam or CreateDialogIndirectParam

With these functions, its a bit more work, but it's possible to imbed a simple dialog template as an initialized static struct in your code. The format of a dialog template has some inplace variable sized arrays, so you have to have a struct declaration that is specific to a particular dialog, but this works OK for debug code.

Something like this

#define DLGTITLE  L"Debug"
#define DLGFONT   L"MS Sans Serif"
#define DLGAPPLY  L"&Apply"
#define DLGCANCEL L"&Cancel"
#define NUMCHARS(aa) (sizeof(aa)/sizeof((aa)[0]))
#define IDC_BITMAP 99

#pragma pack(push, 4)                 
static struct { // dltt 

    DWORD  style; 
    DWORD  dwExtendedStyle; 
    WORD   ccontrols; 
    short  x; 
    short  y; 
    short  cx; 
    short  cy; 
    WORD   menu;         // name or ordinal of a menu resource
    WORD   windowClass;  // name or ordinal of a window class
    WCHAR  wszTitle[NUMCHARS(DLGTITLE)]; // title string of the dialog box
    short  pointsize;       // only if DS_SETFONT flag is set
    WCHAR  wszFont[NUMCHARS(DLGFONT)];   // typeface name, if DS_SETFONT is set

    // control info
    //
    struct {
       DWORD  style; 
       DWORD  exStyle; 
       short  x; 
       short  y; 
       short  cx; 
       short  cy; 
       WORD   id; 
       WORD   sysClass;       // 0xFFFF identifies a system window class
       WORD   idClass;        // ordinal of a system window class
       WCHAR  wszTitle[NUMCHARS(DLGAPPLY)];
       WORD   cbCreationData; // bytes of following creation data
//       WORD   wAlign;         // align next control to DWORD boundry.
    } apply;

    struct {
       DWORD  style; 
       DWORD  exStyle; 
       short  x; 
       short  y; 
       short  cx; 
       short  cy; 
       WORD   id; 
       WORD   sysClass;       // 0xFFFF identifies a system window class
       WORD   idClass;        // ordinal of a system window class
       WCHAR  wszTitle[NUMCHARS(DLGCANCEL)];
       WORD   cbCreationData; // bytes of following creation data
    } cancel;

    struct {
       DWORD  style; 
       DWORD  exStyle; 
       short  x; 
       short  y; 
       short  cx; 
       short  cy; 
       WORD   id; 
       WORD   sysClass;       // 0xFFFF identifies a system window class
       WORD   idClass;        // ordinal of a system window class
       WCHAR  wszTitle[1];    // title string or ordinal of a resource
       WORD   cbCreationData; // bytes of following creation data
    } bitmap;

   } g_DebugDlgTemplate = {

   WS_POPUP | WS_VISIBLE | WS_CAPTION | WS_SYSMENU  // style  0x94c800c4
   | DS_MODALFRAME | DS_3DLOOK 
   | DS_SETFONT,
   0x0,        // exStyle;
   3,          // ccontrols
   0, 0, 300, 180,
   0,                       // menu: none
   0,                       // window class: none
   DLGTITLE,                // Window caption
   8,                       // font pointsize
   DLGFONT,

      {
      WS_CHILD | WS_VISIBLE | WS_TABSTOP | WS_GROUP | BS_DEFPUSHBUTTON,   // 0x50030001
      WS_EX_NOPARENTNOTIFY, // 0x4
      190,160,50,14,
      IDOK,
      0xFFFF, 0x0080, // button
      DLGAPPLY, 0,
      },

      {
      WS_CHILD | WS_VISIBLE | WS_TABSTOP | BS_PUSHBUTTON,    // 0x50010000
      WS_EX_NOPARENTNOTIFY, // 0x4
      244,160,50,14,
      IDCANCEL,
      0xFFFF, 0x0080, // button
      DLGCANCEL, 0,
      },

      {
      WS_CHILD | WS_VISIBLE | WS_GROUP | SS_LEFT,    // 0x50020000
      WS_EX_NOPARENTNOTIFY, // 0x4
      6,6,288,8,
      IDC_BITMAP,
      0xFFFF, 0x0082, // static
      L"", 0,
      },
   };

#pragma pack(pop)

INT_PTR CALLBACK Debug_DlgProc (
    HWND   hwnd,
    UINT   uMsg,
    WPARAM wParam,
    LPARAM lParam)
{
    switch (uMsg)
       {
       case WM_INITDIALOG:
           {
           }
           break;

       case WM_COMMAND:
           {
           UINT wId = LOWORD(wParam);
           if (wId == IDOK || wId == IDCANCEL)
              {
              EndDialog (hwnd, wId);
              }
           }
           break;

       case WM_CLOSE:
           EndDialog(hwnd, IDCANCEL);
           break;
       }

    return FALSE;
}


LRESULT DoDebugDialog(HWND hwndApp, LPVOID pvData)
{
   HINSTANCE hinst = hwndApp ? (HINSTANCE)(LONG_PTR)GetWindowLongPtr(hwndApp, GWLP_HINSTANCE) 
                             : (HINSTANCE)GetModuleHandle(NULL);

   return DialogBoxIndirectParamW (hinst, (LPCDLGTEMPLATEW)&g_DebugDlgTemplate, hwndApp,
                                  Debug_DlgProc, (LPARAM)pvData);
}

A more sophisticated solution would be to build up a dialog template structure in memory, but this works well for debug code where the dialog itself doesn't change much.