How to Close a wpf window in particular idletime?

private void Window_Loaded(object sender, RoutedEventArgs e)
{
    playSwf();
    //System.Windows.Forms.Application.Idle += new EventHandler(Application_Idle);
    string todayDate = DateTime.Now.ToShortDateString();

    try
    {
        var functionRecs = from recs in Window1.mcsCtx.mcs_function
                           orderby recs.mcs_Function_FromTime
                           select recs;
        lbl_head1.Content = functionRecs.First().mcs_Function_PartyName.ToString();
        lbl_sub1.Content = functionRecs.First().mcs_Function_HallName.ToString();
        lbl_Time1.Content = functionRecs.First().mcs_Function_FromTime.ToString();
        lFunctions = functionRecs.ToList();

        // display restaurant names
        updateFunctionList(nBlock);

        var scrollrecs = from recs in Window1.mcsCtx.mcs_scroll select recs;
        string tit = scrollrecs.First().mcs_Scroll_Title.ToString();
        string descrip = scrollrecs.First().mcs_Scroll_Description.ToString();
        AddTextBlock(tit + "   " + descrip);
    }
    catch
    {
        MessageBox.Show("Check the Connection");
    }

    canvas1.Dispatcher.BeginInvoke(DispatcherPriority.Background, new DispatcherOperationCallback(delegate(Object state)
    {
        var node = textBlocks.First;

        while (node != null)
        {
            //double left = 0;

            if (node.Previous != null)
            {
                Canvas.SetLeft(node.Value, Canvas.GetLeft(node.Previous.Value) + node.Previous.Value.ActualWidth + gap);
            }
            else
            {
                Canvas.SetLeft(node.Value, canvas1.Width + gap);
            }

            node = node.Next;
        }

        return null;

    }), null);
    timer.Interval = timer_interval;
    timer.Elapsed += new ElapsedEventHandler(timer_Elapsed);
    //timer.Start();
    timer.Enabled = true;

    IdleTimer.Interval = 1;
    IdleTimer.Elapsed += new ElapsedEventHandler(IdleTimer_Elapsed);
    //IdleTimer.Start();
    IdleTimer.Enabled = true;
}

void IdleTimer_Elapsed(object sender, ElapsedEventArgs e)
{
    try
    {
        var idletimerecs = from recs in Window1.mcsCtx.mcs_idletimer
                           select recs;
        int idletimedb = idletimerecs.First().mcs_IdleTimer_Time;
        int itime = idletimedb * 100;
        idleCounter++;

        if (idleCounter == itime)
        {
            //MessageBox.Show(""+itime);
            //Thread.CurrentThread.Abort();
            //IdleTimer.Enabled = false;
            fn();
            //Window1 win1 = new Window1();
            //win1.Show();
        }
    }
    catch//(Exception er)
    {
       // MessageBox.Show("ERROR"+er);
    }
}

void fn()
{
    try
    {
        //timer.Enabled = false;
        //IdleTimer.Enabled = false;
        this.Close();
    }
    catch (Exception exa)
    {
        MessageBox.Show("" + exa);
        //MessageBox.Show(""+exa.InnerException);
    }
    //ButtonAutomationPeer peer = new ButtonAutomationPeer(btn_openMain);
    //IInvokeProvider invokeProv = peer.GetPattern(PatternInterface.Invoke) as IInvokeProvider;
    //invokeProv.Invoke();
}
void timer_Elapsed(object sender, ElapsedEventArgs e)
{
    canvas1.Dispatcher.BeginInvoke(DispatcherPriority.Background, new DispatcherOperationCallback(delegate(Object state)
    {
        var node = textBlocks.First;
        var lastNode = textBlocks.Last;

        while (node != null)
        {
            double newLeft = Canvas.GetLeft(node.Value) - move_amount;

            if (newLeft < (0 - (node.Value.ActualWidth + gap)))
            {
                textBlocks.Remove(node);

                var lastNodeLeftPos = Canvas.GetLeft(lastNode.Value);

                textBlocks.AddLast(node);

                if ((lastNodeLeftPos + lastNode.Value.ActualWidth + gap) > canvas1.Width) // Last element is offscreen
                {
                    newLeft = lastNodeLeftPos + lastNode.Value.ActualWidth + gap;
                }
                else
                {
                    newLeft = canvas1.Width + gap;
                }
            }

            Canvas.SetLeft(node.Value, newLeft);

            node = node == lastNode ? null : node.Next;
        }

        return null;

    }), null);
}

void AddTextBlock(string Text)
{
    TextBlock tb = new TextBlock();
    tb.Text = Text;
    tb.FontSize = 35;
    tb.FontWeight = FontWeights.Medium;
    tb.Foreground = Brushes.Gold;

    canvas1.Children.Add(tb);

    Canvas.SetTop(tb, -3);
    Canvas.SetLeft(tb, -999);
    Canvas.SetBottom(tb, 3);

    textBlocks.AddLast(tb);
}