c++vbaapidialogmodeless

Using CreateDialog in VBA in an Attempt to Create Modeless Dialog Boxes


I want to create a modeless popup dialog in VBA 7.0. So far the most promising route seems to be CreateDialog.

First I tried CreateDialogW and received Entry point not found for CreateDialogW in DLL.
After opening the DLL, I verified this function was not listed. The MSDN reference linked above shows User32 as the DLL for this function and lists function names CreateDialogW and CreateDialogA (Unicode/ansi respectively), but they are not listed in this DLL on my computer (Win 7 professional, 64bit).

So, looking at the list of functions that are in the DLL, I saw the CreateDialogParam and CreateDialogIndirectParam functions (Ansi and Unicode versions of each).

I've been trying to follow the MSDN and convert the C examples to VB, but I'm missing something somewhere and I'm kind of stuck as I don't know what I'm doing wrong. The code compiles and runs without errors, but nothing happens at the API call - it executes but nothing happens.

If anyone could give me some pointers in the right direction I would greatly appreciate it. My current workaround sucks, and I'd really like to button this project up.

Option Explicit

'Reference conversion of C to VB type declarations here
'http://msdn.microsoft.com/en-us/library/aa261773(v=vs.60).aspx

'Declare function to Win API CreateDialog function
'http://msdn.microsoft.com/en-us/library/ms645434(v=vs.85).aspx
Private Declare PtrSafe Function CreateDialog Lib "User32.dll" Alias "CreateDialogParamW" _
                                (ByVal lpTemplateName As LongPtr, _
                                 ByRef lpDialogFunc As DIALOGPROC, _
                                 ByVal dwInitParam As Long, _
                                 Optional ByVal hInstance As Long, _
                                 Optional ByVal hWndParent As Long) _
                                As Long

'Windows Style Constants
'http://msdn.microsoft.com/en-us/library/windows/desktop/ms632600(v=vs.85).aspx
Public Const WS_BORDER As Long = &H800000
Public Const WS_CAPTION As Long = &HC00000
Public Const WS_CHILD As Long = &H40000000
Public Const WS_CHILDWINDOW As Long = &H40000000
Public Const WS_CLIPCHILDREN As Long = &H2000000
Public Const WS_CLIPSIBLINGS As Long = &H4000000
Public Const WS_DISABLED As Long = &H8000000
Public Const WS_DLGFRAME As Long = &H400000
Public Const WS_GROUP As Long = &H20000
Public Const WS_HSCROLL As Long = &H100000
Public Const WS_ICONIC As Long = &H20000000
Public Const WS_MAXIMIZE As Long = &H1000000
Public Const WS_MAXIMIZEBOX As Long = &H10000
Public Const WS_MINIMIZE As Long = &H20000000
Public Const WS_MINIMIZEBOX As Long = &H20000
Public Const WS_OVERLAPPED As Long = &H0
Public Const WS_POPUP As Long = &H80000000
Public Const WS_SIZEBOX As Long = &H40000
Public Const WS_SYSMENU As Long = &H80000
Public Const WS_TABSTOP As Long = &H10000
Public Const WS_THICKFRAME As Long = &H40000
Public Const WS_TILED As Long = &H0
Public Const WS_VISIBLE As Long = &H10000000
Public Const WS_VSCROLL As Long = &H200000
Public Const WS_OVERLAPPEDWINDOW As Long = (WS_OVERLAPPED + WS_CAPTION + WS_SYSMENU + WS_THICKFRAME + WS_MINIMIZEBOX + WS_MAXIMIZEBOX)
Public Const WS_TILEDWINDOW As Long = (WS_OVERLAPPED + WS_CAPTION + WS_SYSMENU + WS_THICKFRAME + WS_MINIMIZEBOX + WS_MAXIMIZEBOX)
Public Const WS_POPUPWINDOW As Long = (WS_POPUP + WS_BORDER + WS_SYSMENU)

'Declare custom type for lpDialogFunc argument
'http://msdn.microsoft.com/en-us/library/windows/desktop/ms645469(v=vs.85).aspx
Public Type DIALOGPROC
    hwndDlg As Long
    uMsg As LongPtr
    wparam As Long
    lparam As Long
End Type


'MAKEINTRESOURCE Macro emulation
'http://msdn.microsoft.com/en-us/library/windows/desktop/ms648029(v=vs.85).aspx
'Bitwise function example found here: http://support.microsoft.com/kb/112651
'VB conversion found here: https://groups.google.com/forum/#!topic/microsoft.public.vb.winapi/UaK3S-bJaiQ _
 modified with strong typing and to use string pointers for VB7
Private Function MAKEINTRESOURCE(ByVal lID As Long) As LongPtr
     MAKEINTRESOURCE = StrPtr("#" & CStr(MAKELONG(lID, 0)))
End Function

Private Function MAKELONG(ByRef wLow As Long, ByRef wHi As Long)
    'Declare variables
        Dim LoLO            As Long
        Dim HiLO            As Long
        Dim LoHI            As Long
        Dim HiHI            As Long

    'Get the HIGH and LOW order words from the long integer value
        GetHiLoWord wLow, LoLO, HiLO
        GetHiLoWord wHi, LoHI, HiHI

            If (wHi And &H8000&) Then
                MAKELONG = (((wHi And &H7FFF&) * 65536) Or (wLow And &HFFFF&)) Or &H80000000
            Else
                MAKELONG = LoLO Or (&H10000 * LoHI)
                'MAKELONG = ((wHi * 65535) + wLow)
            End If
End Function

Private Function GetHiLoWord(lparam As Long, LOWORD As Long, HIWORD As Long)
    'This is the LOWORD of the lParam:
        LOWORD = lparam And &HFFFF&
    'LOWORD now equals 65,535 or &HFFFF
    'This is the HIWORD of the lParam:
        HIWORD = lparam \ &H10000 And &HFFFF&
    'HIWORD now equals 30,583 or &H7777
        GetHiLoWord = 1
End Function

Public Function TstDialog()
    Dim dpDialog                As DIALOGPROC

    dpDialog.hwndDlg = 0
    dpDialog.uMsg = StrPtr("TEST")
    dpDialog.lparam = 0
    dpDialog.wparam = 0

    CreateDialog hInstance:=0, lpTemplateName:=MAKEINTRESOURCE(WS_POPUPWINDOW + WS_VISIBLE), lpDialogFunc:=dpDialog, dwInitParam:=&H110
End Function

Solution

  • This can be made to work, although if you should try to make it work is another question. I have a working version that shows an empty dialog. I don't have any more time tonight to finish with actual controls on the dialog, but I'm posting in the hope it'll get you started.

    First you need to forget about CreateDialog because they require the dialog template to be in the resource section. You can use CreateDialogIndirectParam to create a dialog from an in-memory dialog template. You will need this:

    Private Type DLGTEMPLATE
        style As Long
        dwExtendedStyle As Long
        cdit As Integer
        x As Integer
        y As Integer
        cx As Integer
        cy As Integer
    End Type
    
    Private Type DLGITEMTEMPLATE
        style As Long
        dwExtendedStyle As Long
        x As Integer
        y As Integer
        cx As Integer
        cy As Integer
        id As Integer
    End Type
    
    Private Type DLG
        dlgtemp As dlgtemplate
        menu As Long
        classname As String
        title As String
    End Type
    
    Private Declare PtrSafe Function CreateDialogIndirectParam Lib "User32.dll" Alias "CreateDialogIndirectParamW" _
      (ByVal hInstance As Long, _
      ByRef lpTemplate As DLGTEMPLATE, _
      ByVal hWndParent As Long, _
      ByVal lpDialogFunc As LongPtr, _
      ByVal lParamInit As Long) _
      As LongPtr
    
    Const WM_INITDIALOG As Long = &H110
    Const DS_CENTER As Long = &H800&
    Const DS_SETFONT As Long = &H40
    Const DS_MODALFRAME As Long = &H80
    Const WS_EX_APPWINDOW As Long = &H40000
    

    Then call it like this:

    Dim d As DLG
    d.dlgtemp.style = DS_MODALFRAME + WS_POPUP + WS_VISIBLE + WS_CAPTION + WS_SYSMENU
    d.dlgtemp.dwExtendedStyle = WS_EX_APPWINDOW
    d.dlgtemp.cdit = 0
    d.dlgtemp.x = 100
    d.dlgtemp.y = 100
    d.dlgtemp.cx = 200
    d.dlgtemp.cy = 200
    d.menu = 0
    d.title = "Test"
    d.classname = "Test"
    
    CreateDialogIndirectParam 0, d.dlgtemp, 0, AddressOf DlgFunc, 0
    

    with DlgFunc looking something like this:

    Public Function DlgFunc(ByVal hwndDlg As LongPtr, ByVal uMsg As LongPtr, ByVal wParam As LongPtr, ByVal lParam As LongPtr) As LongPtr
        If uMsg = h110 Then  ' = WM_INITDIALOG - you should make a const for the various window messages you'll need...
            DlgFunc = True
        Else
            DlgFunc = False
        End If
    End Function
    

    It's been over a decade since I last did any of this stuff. But if you're determined to go this route, I think this approach is the most promising - the next step is to adapt the DLG struct to add some DLGITEMTEMPLATE members, set d.dlgtemp.cdit to the number of controls on your dialog, and start handling control messages in your DlgFunc.