private void treeView1_AfterSelect(object sender, System.Windows.Forms.TreeViewEventArgs e)
        {
            string       key  = e.Node.FullPath;
            SettingsPage page = SettingsPages[key];

            Settings.Gui.InitialSettingsPage = key;

            if (page != null && page != current)
            {
                panel1.Controls.Clear();
                panel1.Controls.Add(page);
                page.Dock = DockStyle.Fill;
                current   = page;
                return;
            }
        }
 public void Add(SettingsPage page)
 {
     this.InnerList.Add(page);
 }