How to show a MFC dialog without stealing focus on the other window

I have the dialog shown with ShowWindow(hWnd, SW_SHOWNOACTIVATE); But it doesn't work, the new dialog still steals the focus, why is it?

here is the some code snippets from my program, Q开发者_Go百科ueryWindow is the MFC dialog class linked with the dialog:

QueryWindow window;
//window.DoModal();
window.Create(QueryWindow::IDD);
window.ShowWindow(SW_SHOWNOACTIVATE);

There are few ways to skip dialog from getting focused:

• Make you OnInitDialog() to return zero value. Example:

  BOOL QueryWindow::OnInitDialog()
  {
      CDialog::OnInitDialog();
  
      return FALSE; // return 0 to tell MFC not to activate dialog window
  }
  

  This is the best and most correct solution.

• Add WS_EX_NOACTIVATE style to your dialog window. You can edit dialog resource properties or change it in runtime:

  BOOL QueryWindow::PreCreateWindow(CREATESTRUCT& cs)
  {
      cs.dwExStyle |= WS_EX_NOACTIVATE;
  
      return CDialog::PreCreateWindow(cs);
  }
  

  Side-effect: you can use controls on your window, but it will look like it was not activated.

• Last way is to save foreground window before creating your dialog and set foreground window at the end:

  BOOL QueryWindow::Create(LPCTSTR lpszTemplateName, CWnd* pParentWnd)
  {
      CWnd* pForeground = GetForegroundWindow();
  
      const BOOL bRes = CAlertDialog::Create(lpszTemplateName, pParentWnd);
  
      if(pForeground)
          pForeground->SetForegroundWindow();
      return bRes;
  }
  

  This is the worth solution because potentially you can get flicker.

Important!

Don't forget to control following API calls:

• ShowWindow - you can use SW_SHOWNOACTIVATE, but can't use SW_SHOW
• SetWindowPos - add flag SWP_NOACTIVATE