VBX in resource only DLL

Filippo Davalli -- filippod@mbox.vol.it
Sunday, April 28, 1996

Hello,

My environment is : Visual C++ 1.51, MFC 2.51 / WIN 95

I'm implementing a multilingual application 16 bits. 
I wrote a series of single language resource DLLs and
the program runs fine. 
But if I add a VBX control in a dialog, this becomes hidden.

The DLL project contains

resource.cpp with this code only:

#include 
int CALLBACK LibMain(HINSTANCE hInstance,WORD,WORD,LPSTR)
{
    return 1;   
}

resource.rc (strings, dialogs, bitmaps, menus...)

resource.def

LIBRARY      RESOURCE
EXETYPE      WINDOWS
CODE         PRELOAD MOVEABLE DISCARDABLE
DATA         PRELOAD MOVEABLE SINGLE
SEGMENTS
    _TEXT   PRELOAD MOVEABLE DISCARDABLE
    WEP_TEXT PRELOAD MOVEABLE DISCARDABLE

HEAPSIZE     1024
EXPORTS
    WEP @1 RESIDENTNAME PRIVATE

To use a resource-only DLL, my program load it using
a call to ::LoadLibrary :

m_hInstDLL = ::LoadLibrary("resource.dll");
AfxSetResourceHandle(m_hInstDLL);

Nothing changes if I add this in LibMain:

int FAR PASCAL LibMain (HANDLE hInstance, WORD wDataSeg,                
       WORD wHeapSize, LPSTR lpszCmdLine)
{
     WNDCLASS wndClass;
     if(::GetClassInfo(hInstance,"VBControl",&wndClass)==0)
     {
      	wndClass.hInstance = hInstance; 
      	::RegisterClass(&wndClass);
     }
  
     return 1 ;
}

Does anyone know how to put a VBX in a dialog 
with a resource only DLL ?

F. Davalli

---

Stacey Blaschke -- Stacey_Blaschke@msn.com
Tuesday, April 30, 1996

[Mini-digest: 2 responses]

You said you are using MFC but not whether this is an AFXDLL or an  USRDLL.If 
it is an AFXDLL then take a look at the PSS article Q104239
(available on MSDN or the MS Web site) for an example
of this.

Basically from the code you posted you are leaving out
the second call to GetClassInfo (see below) which
actually fills the wndClass structure with information
about the VBControl class using the calling applications
instance handle. The first call just checks
for the existence of the class and does not fill the
structure if it does not find the class. Also, take a 
look at the comment the code below. In your
calling application you must have called EnableVBX 
in order for the line:

VERIFY(::GetClassInfo(AfxGetInstanceHandle(),"VBControl",
                           &wndClass));

to find the already registered class. So you have to call
EnableVBX before you call LoadLibrary.


// Check to see if the class is already registered.
   if(::GetClassInfo(hInstDLL,"VBControl",&wndClass)==0)
    {
     // If not registered, get the class information from the
     // application. This assumes that the application has called
     // EnableVBX to register the VBControl class.
     VERIFY(::GetClassInfo(AfxGetInstanceHandle(),"VBControl",
                           &wndClass));
     wndClass.hInstance = hInstDLL; // Change the instance handle so
                                    // it is that of the DLL and not
                                    // the App.
     VERIFY(::RegisterClass(&wndClass));  // Register the class.
    }

Stacey_Blaschke@msn.com

-----From: Phil Reeves 

I have never tried what this, but one thought that occurs is that you need
to make sure EnableVBX() is called before you try to use the dialog
otherwise it will not appear.
Philip Reeves
Knowledge Engineer
Royal Brompton Hospital
Sydney Street
London
SW3 6NP
UK
Tel: +44 (0)171 351 8702
Fax: +44 (0)171 351 8743
e-mail: p.reeves@rbh.nthames.nhs.uk

---

| Вернуться в корень Архива |