C / C++ / MFC

...
#include "TestDoc.h"
#include "MainFrm.h"
...
CTestDoc* pDoc = (CTestDoc*)((CMainFrame*) AfxGetMainWnd())->GetActiveDocument();

• Set the tab control's "transparent" bit (in the resource editor) to true.
  
  
• Call BringWindowToTop() followed by SetFocus() to properly show the selected modeless dialog.

/////////////////////////////////////////////////////////////////////////////
// CDlgHolding dialog
 
BEGIN_MESSAGE_MAP(CDlgHolding, CDialog)
	//{{AFX_MSG_MAP(CDlgHolding)
	ON_NOTIFY(TCN_SELCHANGE, TAB_CTRL, OnTabSelected)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()
 
/////////////////////////////////////////////////////////////////////////////
// CDlgHolding message handlers
 
BOOL CDlgHolding::OnInitDialog() 
{
	CDialog::OnInitDialog();
	
  // Initialize tab control
  CTabCtrl* pTabCtrl = (CTabCtrl *) GetDlgItem (TAB_CTRL);
  ASSERT (pTabCtrl != NULL);
  pTabCtrl->InsertItem (0, " Stock Holding ");
  pTabCtrl->InsertItem (1, " Cash Holding ");
  pTabCtrl->InsertItem (2, " Margin Debt ");
 
  // Create tabbed dialogs
  VERIFY (m_dlgStockHolding.Create (IDD_STOCK_HOLDING, this));
  VERIFY (m_dlgCashHolding.Create (IDD_CASH_HOLDING, this));
  VERIFY (m_dlgMarginHolding.Create (IDD_MARGIN_HOLDING, this));
  updateTabSelection();
 
  // Set focus to default tab
  m_dlgStockHolding.SetFocus();

  return FALSE; // return TRUE unless you set the focus to a control
                // EXCEPTION: OCX Property Pages should return FALSE
}
 
void CDlgHolding::OnTabSelected
  (NMHDR* pNMHDR, LRESULT* pResult) 
{
  // Set new current tab
  CTabCtrl* pTabCtrl = (CTabCtrl *) GetDlgItem (TAB_CTRL);
  ASSERT (pTabCtrl != NULL);
  long nCurrentTab = pTabCtrl->GetCurSel();
 
  // Hide all tabbed dialogs
  m_dlgStockHolding.ShowWindow (SW_HIDE);
  m_dlgCashHolding.ShowWindow (SW_HIDE);
  m_dlgMarginHolding.ShowWindow (SW_HIDE);
 
  // Get window of visible tabbed dialog
  CWnd* pWndCurrentTab = NULL;
  switch (nCurrentTab) {
    case 0:
      pWndCurrentTab = &m_dlgStockHolding;
      break;
    case 1:
      pWndCurrentTab = &m_dlgCashHolding;
      break;
    case 2:
      pWndCurrentTab = &m_dlgMarginHolding;
      break;
    default:
      ASSERT (FALSE);
      break;
  }
 
  // Resize and show dialog
  if (pWndCurrentTab != NULL) {
      CRect rectCtrl;
      GetDlgItem (FRAME_TAB_DIALOG)->GetWindowRect (&rectCtrl);
      ScreenToClient (&rectCtrl);

      pWndCurrentTab->MoveWindow (&rectCtrl, TRUE);
      pWndCurrentTab->ShowWindow (SW_SHOW);
      pWndCurrentTab->Invalidate();
      pWndCurrentTab->UpdateWindow();
      pWndCurrentTab->BringWindowToTop();
      pWndCurrentTab->SetFocus();
  }
 
  // Return normally
	*pResult = 0;
}
 
// End DlgHolding.cpp

GetDlgItem (FRAME_TAB_DIALOG)->GetWindowRect (&rectCtrl)