public CounterManager()
        {
            InitializeComponent();
            db               = Model.DatabaseConfigure.getConfigure();
            instance         = this;
            this.FormClosed += (o, e) =>
            {
                instance = null;
            };

            foreach (var counter in db.counters.ToList())
            {
                flowLayoutPanel.Controls.Add(new Viwer(counter.id));
            }
        }
 public static void show(Panel p)
 {
     if (instance == null)
     {
         var newlist = new CounterManager();
         newlist.TopLevel = false;
         newlist.Dock     = DockStyle.Fill;
         p.Controls.Add(newlist);
         newlist.Show();
         newlist.BringToFront();
     }
     else
     {
         instance.BringToFront();
     }
 }