public new void Start()
        {
            base.Start();

            var root = visualTree;

            var popupWindow = new PopupWindow();

            popupWindow.text = "New Task";
            root.Add(popupWindow);

            m_TextField = new TextField {
                name = "input", viewDataKey = "input", isDelayed = true
            };
            popupWindow.Add(m_TextField);
            m_TextField.RegisterCallback <KeyDownEvent>(AddTask);

            var button = new Button(AddTask)
            {
                text = "Save task"
            };

            popupWindow.Add(button);

            var box = new Box();

            m_TasksContainer = new ScrollView();
            m_TasksContainer.showHorizontal = false;
            box.Add(m_TasksContainer);

            root.Add(box);
        }