FIX: Icons, Bitmaps, & Menus Not Displayed in an AFXDLL Dialog

RESOLUTION

To correct this problem, you have to set the current handle to be the one that corresponds to the module containing a dialog template. You also need to reset the handle back to the old value before proceeding with any code that involves the dialog. The easiest way to achieve this is to override DoModal in your CDialog derived class as in this example:

int CMyDialog::DoModal()
{
    m_hInstSave = afxCurrentInstanceHandle;
    afxCurrentInstanceHandle = AfxFindResourceHandle(
        MAKEINTRESOURCE(IDD), RT_DIALOG);

    return CDialog::DoModal();
}
				

Here m_hInstSave is a data member of CMyDialog of type HINSTANCE. The variable afxCurrentInstanceHandle is used by MFC to store the current instance handle. Its value is returned from AfxGetInstanceHandle(), and it is defined in Afxwin.h.

This implementation sets the current instance handle to the one that is returned from AfxFindResourceHandle(), which searches through the list of available extension DLLs for a dialog template. If you are using a resource only DLL, you will probably use AfxSetResourceHandle() to set the MFC current resource handle to the one that corresponds to the DLL. In that case, you can set afxCurrentInstanceHandle either directly using the same value or with a value returned from AfxGetResourceHandle().

To reset the current instance handle back to the saved value, you need to have a handler for the WM_INITDIALOG message, OnInitDialog, with the following code:

BOOL CMyDialog::OnInitDialog()
{
    afxCurrentInstanceHandle=m_hInstSave;

    CDialog::OnInitDialog();

    // some other code...

    return TRUE;
}