CGridCtrl in CCtrlView

I am trying to use CGridCtrl inside of CCtrlView, in an MDI app. And I wrote this:

Code:

---

class CTestGridView : public CCtrlView
{
protected: // create from serialization only
        CTestGridView();
        DECLARE_DYNCREATE(CTestGridView)

// Attributes
public:
        CTestGridDoc* GetDocument() const;
        CGridCtrl& GetGridCtrl() const {return *(CGridCtrl*)this;}
....
}

---

and in cpp:

Code:

---

CTestGridView::CTestGridView()
        :CCtrlView(GRIDCTRL_CLASSNAME, AFX_WS_DEFAULT_VIEW)
{
        // TODO: add construction code here

        WNDCLASS wndcls;
        //HINSTANCE hInst = AfxGetInstanceHandle();
        HINSTANCE hInst = AfxGetResourceHandle();
        if(! (::GetClassInfo(hInst, GRIDCTRL_CLASSNAME, &wndcls)))
        {
                // otherwise we need to register a new class
                wndcls.style                        = CS_DBLCLKS | CS_HREDRAW | CS_VREDRAW;
                wndcls.lpfnWndProc                = ::DefWindowProc;
                wndcls.cbClsExtra                = wndcls.cbWndExtra = 0;
                wndcls.hInstance                = hInst;
                wndcls.hIcon                        = NULL;
#ifndef _WIN32_WCE_NO_CURSOR
                wndcls.hCursor                  = AfxGetApp()->LoadStandardCursor(IDC_ARROW);
#else
                wndcls.hCursor                  = 0;
#endif
                wndcls.hbrBackground        = (HBRUSH) (COLOR_3DFACE + 1);
                wndcls.lpszMenuName                = NULL;
                wndcls.lpszClassName        = GRIDCTRL_CLASSNAME;

                if(! AfxRegisterClass(&wndcls))
                {
                        AfxThrowResourceException();
                }
        }
}

---

Until here, it goes without problem ... but when I am trying to use CGridCtrl object inside, I get a crash:

Code:

---

void CTestGridView::OnInitialUpdate()
{
        CCtrlView::OnInitialUpdate();
       
        CGridCtrl& GridCtrl = (CGridCtrl&)GetGridCtrl();
        GridCtrl.SetRowCount(1); // <-- crash
}

---

and the error is:

Code:

---

Unhandled exception at 0x77ce0ebc (mfc90d.dll) in TestGrid.exe: 0xC0000005: Access violation reading location 0xfeeefeee.

---

Code:

---

        if (!AfxIsValidAddress(pOb, pOb->GetRuntimeClass()->m_nObjectSize, FALSE))
        {
                TRACE(traceAppMsg, 0, "ASSERT_VALID fails with illegal pointer.\n");
                if (AfxAssertFailedLine(lpszFileName, nLine))
                        AfxDebugBreak();
                return;    // quick escape
        }

---

This error has been triggered when grid is trying to call:

Code:

---

        TRY
        {
                m_arRowHeights.SetSize(nRows); // <-- here is firing the crash

---

Is obvious that I done something wrong ... but what ? It is possible what I am trying to do ?

Thank you for any hint/help in solving my task.


P.S. I attach an test app that illustrate the problem.

Code:

---

class CTestGridView : public CCtrlView
{
    // ...
    CGridCtrl& GetGridCtrl() const {return *(CGridCtrl*)this;} // <--bad
    // ...
}

---

It crashes because neither CCtrlView nor CTestGridView has a SetRowCount method.
You tried to apply a "trick" used in another CCtrlView-derived classes. It works there because the control classes (CListCtrl, CTreeCtrl, etc.) has methods that only send messages.
Example:

Code:

---

_AFXCMN_INLINE void CListCtrl::SetItemCount(_In_ int nItems)
        { ASSERT(::IsWindow(m_hWnd)); ::SendMessage(m_hWnd, LVM_SETITEMCOUNT, nItems, 0); }

---

In case of CGridCtrl do the following:

1. add a member of type CGridCtrl to view class (not necessary to be derived from CCtrlView);
2. call CGridCtrl::Create, in WM_CREATE handler of view class;
3. handle WM_SIZE message in view class and resize the grid control.

Here is the code:

Code:

---

class CTestGridView : public CView // not CCtrlView
{
    CGridCtrl m_gridCtrl;
    // ...
};

---

Code:

---

#define GRID_CTRL_ID 1000
// ...

BEGIN_MESSAGE_MAP(CTestGridView, CView)
    // ...
    ON_WM_CREATE()
    ON_WM_SIZE()
END_MESSAGE_MAP()
// ...

int CTestGridView::OnCreate(LPCREATESTRUCT lpCreateStruct)
{
    if (CView::OnCreate(lpCreateStruct) == -1)
        return -1;

    VERIFY(m_gridCtrl.Create(CRect(), this, GRID_CTRL_ID, WS_CHILD | WS_VISIBLE));

    return 0;
}

void CTestGridView::OnSize(UINT nType, int cx, int cy)
{
    CView::OnSize(nType, cx, cy);

    if (m_gridCtrl.GetSafeHwnd())
    {
        m_gridCtrl.SetWindowPos(NULL, 0, 0, cx, cy, SWP_NOZORDER | SWP_NOACTIVATE);
    }
}

void CTestGridView::OnInitialUpdate()
{
    CView::OnInitialUpdate();

    m_gridCtrl.SetRowCount(10);
    m_gridCtrl.SetColumnCount(4);
    // ... and so on.
}

---

So, I should understand that I cannot use CGridCtrl inside of CCtrlView in this way ...

I am using right now this technique, to resize an CGridCtrl object over a CView, but I have met a little bug in this case: when I have CDockablePane on an CChildFrame, and CGridCtrl over CView, because CChildFrame are somehow restored under CGridCtrl ... , yes, this is weird, and this happen even if all child frames are maximized, I could switch between open child frames, as I said before, because some CChildFrame are restored ... I know, it is strange, but this is sort of difficult to reproduce this bug ... I will try to made a test app that illustrate this behavior ...

I would like to use the solution from the first post, but I guess it is impossible ...

I will come back with another test app. Thank you.