void tramvtclick(object sender, RoutedEventArgs e)
 {
     frmtramvt frm = new frmtramvt();
     frm.Show();
 }
 private void ChildWindow_Closed(object sender, EventArgs e)
 {
     frmtramvt frm = new frmtramvt();           
     frm.Show();
 }