How to work with radio buttons for TreeView widget in MonoDevelop?

Question

Mono

Good afternoon, dear development gurus
I am writing a small task manager and trying to use MonoDevelop for this.
Tell me, please, how can I implement the work with switches (check box) in Mono? According to the documentation on the site, I found how you can create collapsible lists for TreeView. The documentation states that a TreeView cell can be rendered as a CellRendererToggle (Used to display a check box), but I can't find any more descriptions on working with this type. I want to implement the ability to set and reset the switch status and then change the data in the model. Now it turned out to only display a column of switches, but I don’t know how to change their status, how the
full project code lies on https://github.com/veitsi/todonet
Now I form the list of tasks like this:

private void TreeInit ()
  {
    Gtk.TreeViewColumn taskColumn = new Gtk.TreeViewColumn ();
    taskColumn.Title = "Task description";
    Gtk.CellRendererText taskTextCell = new Gtk.CellRendererText ();
    taskColumn.PackStart (taskTextCell, true);

    Gtk.TreeViewColumn statusColumn = new Gtk.TreeViewColumn ();
    statusColumn.Title = "status";
    Gtk.CellRendererToggle statusCell = new Gtk.CellRendererToggle ();
    statusColumn.PackStart (statusCell, true);

    tree.AppendColumn (taskColumn);
    tree.AppendColumn (statusColumn);
    taskColumn.AddAttribute (taskTextCell, "text", 0);
    statusColumn.AddAttribute (statusCell, "text", 1);
  }

  public void TreeBuild (ToDoList todo)
  {
    //textview.Buffer.Text = "Загрузили список задач\n";
    this.TreeInit ();

    Gtk.TreeStore todoListStore = new Gtk.TreeStore (typeof(string), typeof(string));
    Gtk.TreeIter iter;
    foreach (Task t in todo.tasks) {
      iter=todoListStore.AppendValues (t.text);
      if (t.subs.Count > 0) {
        foreach (SubTask s in t.subs)
          todoListStore.AppendValues (iter, s.text, "");
      }
    }

    tree.Model = todoListStore;
  }

the program window looks like this