private void ClickEdit(object sender, RoutedEventArgs e)
        {
            switch (SelectedObj)
            {
            case 1:
                Student    x    = theObj as Student;
                NewStudent win6 = new NewStudent(label.Content.ToString(), x.Id);
                win6.deligEven += (s, t) => refreshMyView();
                win6.Show();
                break;

            case 2:
                Teacher    y    = theObj as Teacher;
                NewTeacher win7 = new NewTeacher(label.Content.ToString(), y.Id);
                win7.deligEven += (s, t) => refreshMyView();
                win7.Show();
                break;

            case 3:
                MeetTest    z    = theObj as MeetTest;
                NewMeetTest win8 = new NewMeetTest(label.Content.ToString(), z.TestId.ToString());
                win8.deligEven += (s, t) => refreshMyView();
                win8.Show();
                break;

            case 4:
                ListPermission u    = theObj as ListPermission;
                UserPermissen  win9 = new UserPermissen(label.Content.ToString(), u.Id);
                win9.deligEven += (s, t) => refreshMyView();
                win9.Show();
                break;
            }
        }
        /// <summary>
        /// event click on item
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void ClickAddStudent(object sender, RoutedEventArgs e)
        {
            NewStudent win2 = new NewStudent(label.Content.ToString(), "-1");

            win2.deligEven += (s, t) => refreshMyView();
            win2.Show();
        }