SW_SHOW & SW_HIDE

Hi Guru,

I'm using SDI application

I got two dialogs in resource :
       IDD_MYDIALOG1 (class CMyDlg1) and
       IDD_MYDIALOG2 (class CMyDlg2)

After click the menu ID_TESTDIALOG, it loads IDD_MYDIALOG1, and hide
the Main Frame window, and then it run some timer, and after it meet
some
condition, it will load IDD_MYDIALOG2 and hide both IDD_MYDIALOG1 &
Main Frame window.

Close/destroy IDD_MYDIALOG2 or click save button (OnBtnSave() ) in
IDD_MYDIALOG2 will return to IDD_MYDIALOG1 (while Main frame window
still hide)
Close/destroy IDD_MYDIALOG1 will return to Main Frame Window

In Timer function below, what should I code to hide IDD_MYDIALOG1/Main
frame window and load IDD_MYDIALOG2 ?
In OnBtnSave(), how to return to IDD_MYDIALOG1 with main frame window
hide ?

*****************************************************

BEGIN_MESSAGE_MAP(CMainApp, CWinApp)
    //{{AFX_MSG_MAP(CMainApp)
    ON_COMMAND(ID_TESTDIALOG, OnDialog1Action)
    //}}AFX_MSG_MAP
END_MESSAGE_MAP()

class CMyDlg1 : public CDialog
{

    public:
    CMyDlg1();

    //{{AFX_DATA(CMyDlg1)
    enum { IDD = IDD_MYDIALOG1 };

   ...
}

void CMainApp::OnDialog1Action()
{
    CMyDlg1 Dlg1;
    this->GetMainWnd()->ShowWindow(SW_HIDE);

    Dlg1.DoModal();

    this->GetMainWnd()->ShowWindow(SW_SHOW);

}

void CMyDlg1 ::OnTimer(UINT nIDEvent)
{
     ....
     status = MY_OWN_API_FUNCTION(....)
     if (status = 0)
     {
    // how can I hide this IDD_MYDIALOG1 and also hide MainFrameWindow,
and load IDD_MYDIALOG2 in easiest way ?
     }

     ...
     ...
}

/////////////////////////////////

class CMyDlg2 : public CDialog
{

    public:
    CMyDlg2();

    //{{AFX_DATA(CMyDlg2)
    enum { IDD = IDD_MYDIALOG2 };

   ...
    //{{AFX_MSG(CMyDlg2)
        // No message handlers
    afx_msg void OnBtnSave();
    //}}AFX_MSG
    DECLARE_MESSAGE_MAP()
   ...
}

BEGIN_MESSAGE_MAP(CMyDlg2, CDialog)
    //{{AFX_MSG_MAP(CMyDlg2)
    ON_BN_CLICKED(IDC_BtnSave, OnBtnSave)
    //}}AFX_MSG_MAP
END_MESSAGE_MAP()

void CMyDlg2::OnBtnSave()
{
    // TODO

    // save to DB

      // how to return to IDD_MYDIALOG1 with main frame window hide in
easiest way ?

}

Many thanks.

Regards.