Assertion error when looking for window handle

hi,
I tried implementing a tab control in an SDI document using a CFormView class but I am getting an assertion error:
This is the code I am using:

Code:

// RemoteView.cpp : implementation of the CRemoteView class
//

#include "stdafx.h"
#include "Remote.h"

#include "RemoteDoc.h"
#include "RemoteView.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#endif


// CRemoteView

IMPLEMENT_DYNCREATE(CRemoteView, CFormView)

BEGIN_MESSAGE_MAP(CRemoteView, CFormView)
	ON_NOTIFY(TCN_SELCHANGE, IDC_TAB1, OnTabChange)
END_MESSAGE_MAP()

// CRemoteView construction/destruction

CRemoteView::CRemoteView()
	: CFormView(CRemoteView::IDD)
{
	// TODO: add construction code here

	CRect r;
	TCITEM tci;
	// get dimensions of client area
	GetClientRect(&r);
	// create tab control
	theTabControl.Create(WS_VISIBLE | WS_CHILD,r, this, IDC_TAB1);
	tci.mask = TCIF_TEXT;
	tci.iImage = -1;
	tci.pszText = "One";
	theTabControl.InsertItem(0, &tci);
	tci.pszText = "Two";
	theTabControl.InsertItem(1, &tci);
	tci.pszText = "Three";
	theTabControl.InsertItem(2, &tci);
}

CRemoteView::~CRemoteView()
{
}

void CRemoteView::DoDataExchange(CDataExchange* pDX)
{
	CFormView::DoDataExchange(pDX);
}

BOOL CRemoteView::PreCreateWindow(CREATESTRUCT& cs)
{
	// TODO: Modify the Window class or styles here by modifying
	//  the CREATESTRUCT cs

	return CFormView::PreCreateWindow(cs);
}

void CRemoteView::OnInitialUpdate()
{
	CFormView::OnInitialUpdate();
	GetParentFrame()->RecalcLayout();
	ResizeParentToFit(false);
	//initializeTabs();
}

// CRemoteView message handlers
afx_msg void CRemoteView::OnTabChange(NMHDR *hdr,LRESULT *NotUsed)
{
  CClientDC DC(this);
  char str[255];
  wsprintf(str, "Changed to Tab %d  ",
           theTabControl.GetCurSel()+1); 
  DC.SetBkColor(RGB(200, 200, 200));
  DC.TextOut(40, 100, str, strlen(str));
}

The assertion is occuring in the constructor when GetClientRect(&r) is run.
The assertion error is occuring here:

Code:

_AFXWIN_INLINE void CWnd::GetClientRect(LPRECT lpRect) const
	{ ASSERT(::IsWindow(m_hWnd)); ::GetClientRect(m_hWnd, lpRect); }

It seems it can't find m_hWnd. I was wondering if anybody knew a way around that or could explain why it is so. Thanks
Amish

This is because you are trying to get the window size before the window has been created. If you over-rode OnInitDialog(), you could then call GetClientRect() in the OnCreate() handler with a valid m_hWnd.

Oops, I dont think you can over-ride OnInitDialog() for a CFormView. I think the correct function to over-ride is OnInitialUpdate().

that works. Thanks
Amish