I'm not familiar with MFC but currently I must continue a project that was written in MFC. Now I'm having trouble with the following line when debugging
m_hIcon = AfxGetApp()->LoadIcon (IDR_MAINFRAME);
It always stops after the error "Assertion Failed: at afxwin1.inl". If I put a breakpoint there I saw a NULL icon handle. I tried running in release mode and it worked just fine although the handle is still NULL. I've read this question but my program is not a static library. It's a program that use a dll to connect to a CAN bus device. And the resource IDR_MAINFRAME is already in the project. It contains the default MFC icons. How can I solve this problem?
I've tried debugging and see that pModuleState changes between the first load program name call and the second load icon call. The first call returns successfully because pModuleState points to an object that has valid handle. But in the icon load call, pModuleState points to some object contains NULL handle. I also tried putting AFX_MANAGE_STATE(AfxGetStaticModuleState( )); right above the LoadIcon() call but the problem still arises
I've known the cause of this problem
UINT __cdecl RunCPRead(LPVOID pParam)
{
CMyDlg *thisclass = (CMyDlg *)pParam;
while (thisclass->m_Start)
{
thisclass->GetData();
}
return 0;
}
AfxBeginThread(&RunCPRead, this, THREAD_PRIORITY_NORMAL, 0, 0, NULL);
After the GetData() call in RunCPRead, the control flows directly to CMyDlg's contructor although there's no object being created or copied
CMyDlg::CMyDlg(CWnd* pParent /*=NULL*/)
: CDialog(CMyDlg::IDD, pParent)
{
m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
}
and then fails at the assignment to m_hIcon with the error "access violation while reading". I've seen the disassembly, it was the line mov dword ptr [esi+90h], eax and it's inherently a write to memory.
I don't know why. How can I solve this?
The MFC code need the correct module handle to load the resource.
Please try to read Afx*G/S*etResourceHandle.
By default MFC uses the resource handle of the main application, not of the DLL. If you are making the call in the DLL then add this line at the start of the exported DLL function:
AFX_MANAGE_STATE(AfxGetStaticModuleState( ));
There is more information about this here:
http://msdn.microsoft.com/en-us/library/ba9d5yh5(v=vs.110).aspx
Assertion Errors in MFC usually happens when wrong settings are set.
go to project settings > linker > System and change subsystem to (/SUBSYSTEM:WINDOWS) this solution solved my own problem.
Related
The below code, creating a Property Sheet, works without problem in an Application File.
.......
CProp_Sheet Pr_Sheet(_T("PS"));
CPr_Page_1 Pr_Page_1;
CPr_Page_2 Pr_Page_2;
Pr_Sheet.AddPage(&Pr_Page_1);
Pr_Sheet.AddPage(&Pr_Page_2);
m_pMainWnd = &Pr_Sheet;
int nResponse = Pr_Sheet.DoModal();
However, when I put the same code in a DLL, and call it from a menu item in another Application, m_pMainWnd cannot be used (the menu in the Application is to remain visible behind the Property Sheet).
I have tried to create a handle
CWnd* m_pWnd = &Pr_Sheet;
and use m_pWnd in the CProp_Sheet constructor, but although compiling correctly at run time failure always occurs at
CProp_Sheet::OnInitDialog().
Thanks in advance for any comments.
Problem
I'm trying to open an MFC program that reads a Microsoft Access database (.mdb) and allows the user to view or modify the data. This is an existing program (and source code) given to me by a group in another lab where the program opens and works just fine.
In our lab, I have yet to see it load properly. When run, it pops up a dialog box that says, "Attempted an unsupported operation". Windows then offers me a chance to debug and such before it crashes.
Environment
In the other lab, they use Windows 7 and Microsoft Office 2010, and it works.
In our lab, I've tried Windows 7 with Office 2013 and Windows XP with Office 2010. The latter crashes without giving me the dialog box. I don't know if we have a Win7/MSO2010 machine.
The Function
I have the source code for the program. The solution file implies it was last developed in VS2010, which the computers I tested on had installed as well. Running it out of Visual Studio 2010 or straight from the executable yields the same results.
I have added additional debug dialog boxes to the code that narrow down the problem to this function call, which the code never gets past:
CwinApp:OpenDocumentFile(LPCTSTR lpszPathName)
The single string passed into the function is a path and filename for the MS Access database to be opened. It exists in a temporary directory created by another program. This is on a drive other than C, though I've tested some there, as well. Problems with programs related to this one often stem from files with "read only" status, but I continually check the temporary files created, and they are write-able.
Documentation
I found this information titled "Breaking Changes in Visual C++" for VS2010 through another SO question:
A new virtual function was added to the CDocTemplate class. This new virtual function is CDocTemplate::OpenDocumentFile. The previous version of OpenDocumentFile had two parameters. The new version has three parameters. To support the restart manager, any class derived from CDocTemplate must implement the version that has three parameters. For more information about the function, see CDocTemplate::OpenDocumentFile. The new parameter is bAddToMRU.
Code
I feel this might be the answer! But I don't have a strong idea of exactly what to change to get this to work. Here's where I stopped:
Program.cpp
CDocument* ProgramApp::OpenDocumentFile(LPCTSTR lpszFileName, BOOL bAddToLRU, BOOL bMakeVisible)
{
// Add specialized code here and/or call base class
// Debug messages added
CDocument* tempDoc;
AfxMessageBox(lpszFileName);
tempDoc = CWinApp::OpenDocumentFile(lpszFileName, bAddToMRU);
AfxMessageBox("Opened database!");
return tempDoc;
}
Program.h
class ProgramApp : public CWinApp
{
public:
...
virtual CDocument* OpenDocumentFile(LPCTSTR lpszFileName, BOOL bAddToMRU, BOOL bMakeVisible);
afxwin.h
class CWinApp : public CWinThread
{
...
virtual CDocument* OpenDocumentFile(LPCTSTR lpszFileName);
virtual CDocument* OpenDocumentFile(LPCTSTR lpszFileName, BOOL bAddToMRU);
Changing the Program.cpp call to be from a "Template" class caused errors, but I wouldn't be surprised if that's towards the answer. This solution looks similar, but I'm not sure exactly what to do.
My hope is that this problem has a simple solution that someone more knowledgeable can give me. I would be much appreciative, and additional context would help a lot.
Edit: Debugging
I drilled down into the Windows code to see what was precisely going wrong. It seemed too dense to understand, but a coworker and I may have clues based on it. The failure message happens here:
dlgdata.cpp
// Could be a windowless OCX
pSite = m_pDlgWnd->GetOldControlSite(nIDC);
if (pSite == NULL)
{
TRACE(traceAppMsg, 0, "Error: no data exchange control with ID 0x%04x.\n", nIDC);
ASSERT(FALSE);
AfxThrowNotSupportedException();
}
...Although we are seeing debugger issues here:
occcont.cpp
COleControlSiteOrWnd *pemp = new COleControlSiteOrWnd(hwndCtrl, pOccDlgInfo->m_pItemInfo[i].bAutoRadioButton);
ASSERT(IsWindow(pTemp->m_hWnd));
if (IsWindow(pTemp->m_hWnd))
{
hwndStart = pTemp->m_hWnd;
...
My coworker believes this could have little to do with the opening of this document as I suspected and more to do with objects/controls we don't have on our lab computers trying to be used for the program.
I have faced the same problem in opendocumentfile(), there was a control in CFormView class which i was not using so i commented it out but forget to delete from .rc file. Once i remove the control entry from .rc file the problem disappear.
there should be no control variable uninitialize , please check that also
I have a class named CMyPrintDialog derived from CPrintDialog of MFC. It's used as an ActiveX in IE, and the project is linked to MFC statically. It works well in IE8 for many years.
But the same binary of the project doesn't work well on IE10. The print dialog could pop up, but unfortunately its OnInitDialog is never called and causes problems.
The strange thing is that if I attach the VS debugger to IE, OnInitDialog will be called correctly and the customized print dialog works well.
Seems Microsoft has change something and causes the problem.
I found a similar link but it doesn't work.
Thanks a million for any ideas.
The issue is caused by IE's new feature after IE9 - "Hang Resistance". We can avoid the issue by disabling the new feature: Set below value as 0, and close all IE windows. HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main\ Type: REG_DWORD Name: HangRecovery Value: 0
I am not getting your point exactly you want to say, Consider CPrintDialog crash your application with IE10.What is you need to do is,
Set up the message hook function, _AfxCommDlgProc(), in the constructor of your
CPrintDialog-derived class as shown below:
// CMyPrintDialog is a CPrintDialog-derived class.
CMyPrintDialog::CMyPrintDialog(DWORD dwFlags)
: CPrintDialog(FALSE,dwFlags)
{
//{{AFX_DATA_INIT(CMyPrintDialog)
//}}AFX_DATA_INIT
// MFCBUG: MFC 6.0 doesn't set the message hook!
m_pd.Flags |= PD_ENABLEPRINTHOOK | PD_ENABLESETUPHOOK;
// _AfxCommDlgProc is exported from static MFC libraries
m_pd.lpfnPrintHook = _AfxCommDlgProc;
m_pd.lpfnSetupHook = _AfxCommDlgProc;
}
I have created an MFCApp using VS2008 wizard. Inside my application's "InitInstance()" I'm calling "LoadLibraryA()" method as I need to load a few dll files. But as soon as I call "LoadLibraryA()", it again calls "InitInstance()" of my application and hence it becomes a infinite recursion stuff. Is there something I'm doing wrong?
// CLoader_MFCApp initialization
BOOL CLoader_MFCApp::InitInstance()
{
INITCOMMONCONTROLSEX InitCtrls;
InitCtrls.dwSize = sizeof(InitCtrls);
InitCtrls.dwICC = ICC_WIN95_CLASSES;
InitCommonControlsEx(&InitCtrls);
CWinAppEx::InitInstance();
SetRegistryKey(_T("MyApp"));
HMODULE hm = LoadLibraryA("./abc/def.dll");
// after above line InitInstance() gets called again
// more code
return FALSE;
}
Call Stack:
MyApp.exe!CLoader_MFCApp::InitInstance() C++
CORE.dll!InternalDllMain(HINSTANCE__ *, unsigned long, void *) C++
CORE.dll!__DllMainCRTStartup(void *, unsigned long, void *) C
CORE.dll!_DllMainCRTStartup(void *, unsigned long, void *) C
ntdll.dll!_LdrpCallInitRoutine#16()
ntdll.dll!_LdrpRunInitializeRoutines#4()
ntdll.dll!_LdrpLoadDll#24()
ntdll.dll!_LdrLoadDll#16()
kernel32.dll!_LoadLibraryExW#12()
kernel32.dll!_LoadLibraryExA#12()
kernel32.dll!_LoadLibraryA#4()
MyApp.exe!CLoader_MFCApp::InitInstance() C++
mfc90.dll!AfxWinMain(HINSTANCE__ *, HINSTANCE__ *, char *, int) C++
MyApp.exe!__tmainCRTStartup() C
kernel32.dll!_BaseProcessStart#4()
"Def.dll" is any other dll and completely unrelated from MyApp. In this case, I'm trying to load another dll "CORE.dll"
All I can figure out is that I'm calling LoadLibrary before InitInstance routine is over. Is there any other (overridable) method which is called after InitInstance??? If so, I can try moving LoadLibrary calls to that method...
Yes, you are doing something wrong.
You are in mfc90.dll's DllMain and it is not safe to call LoadLibrary from DllMain, says so right here:
http://msdn.microsoft.com/en-us/library/ms684175%28v=vs.85%29.aspx
This is more of a workaround than a true solution (i.e. I don't know the rules for LoadLibrary in MFC, as I've never read anything to say you can't, nor do I happen to use this technique in our MFC code).
However, Generally speaking, if windows coughs up a hairball due to order of operations, I just move the calls out to another message handler. You can even post a thread message to your application, and write a handler for that message.
Something like:
// in InitInstance - post a message to our main thread to handle after init instance...
PostMessage(NULL, WM_PostInit);
// in your message table
ON_THREAD_MESSAGE(WM_PostInit, OnPostInit)
// in your app
void MyApp::OnPostInit(WPARAM,LPARAM) // both args unused
{
// try load library now...!
}
NOTE: The above is "brain code" - untested. Details undoubtedly need to be massaged for full compilability.
References:
http://msdn.microsoft.com/en-us/library/ms644944%28v=VS.85%29.aspx
I've just had the same issue, caused by the Configuration type being incorrectly set to exe not dll for the dll to be loaded.
Fix: Project -> Configuration Properties -> General -> Configuration Type = Dynamic Library (.dll) (was incorrectly set to Application (.exe))
My MFC application using the "ESRI MapObjects LT2" ActiveX plugin throws an ASSERT at me when closing it.
The error occurs in cmdtarg.cpp:
CCmdTarget::~CCmdTarget()
{
#ifndef _AFX_NO_OLE_SUPPORT
if (m_xDispatch.m_vtbl != 0)
((COleDispatchImpl*)&m_xDispatch)->Disconnect();
ASSERT(m_dwRef <= 1); //<--- Fails because m_dwRef is 3
#endif
m_pModuleState = NULL;
}
I built the (native C++) application with VC9.
When I compile the application with VC6, it behaves nicely.
What could be the reason for this?
That looks like a reference count. Could this "target" be referenced by something else, something that's not releasing it?
You can trace the Addref and Release calls defining _ATL_DEBUG_INTERFACES
from http://msdn.microsoft.com/en-us/library/sycfy8ec(VS.80).aspx
_ATL_DEBUG_INTERFACES
Define this macro before including any ATL header files to trace all AddRef and Release calls on your components' interfaces to the output window.
Using _ATL_DEBUG_INTERFACES did not yield any additional output...
I defined it on the first line of stdafx.h, directly after #pragma once so I guess this is early enough.
Maybe the reason is how I am using the ActiveX control:
I'm not calling AddRef() or Release() by myself.
The MapObjects Installer comes with sample code with lots of wrapper classes which must have been generated by VC6 or something earlier.
I tried to generate wrapper classes myself with VC9 but there occured errors which I wasn't able to fix.
I use the control by letting one of my windows have a member of type CMap1 (derived from CWnd), which is one of those generated wrapper classes. In CMyWnd::OnCreate() I also call CMap1::Create() and that's it, I'm finished: I can add a layer and the control displays a world map.
I have pretty much no idea what the reference-count stuff is about as I have not added or released any references. At least not knowingly...
The control is pretty old: The .OCX file has the year 2000 in its version information.
It's also not officially supported anymore but I don't have any substitue.
The following solved it for me:
In the window that contains the control, add an OnDestroy() handler:
void CMyWnd::OnDestroy()
{
// Apparently we have to disconnect the (ActiveX) Map control manually
// with this undocumented method.
COleControlSite* pSite = GetOleControlSite(MY_DIALOG_CONTROL_ID);
if(NULL != pSite)
{
pSite->ExternalDisconnect();
}
CWnd::OnDestroy();
}