private void CloseWaitDialog()
 {
     if (_waitDialog != null)
     {
         _waitDialog.Close();
         _waitDialog = null;
     }
 }
        private void ShowWaitDialog(string message)
        {
            CloseWaitDialog();

            _waitDialog             = new CancellableWaitDialog();
            _waitDialog.FormClosed += new FormClosedEventHandler(_waitDialog_FormClosed);
            _waitDialog.ShowDialog(message, this);
        }