Inheritance: INotifyPropertyChanged
        public Settings(AppBar appbar)
        {
            InitializeComponent();

            DataContext = Model = new SettingsModel(appbar);

            Owner = appbar;
            ShowDialog();
        }
        public Settings(Sidebar sidebar)
        {
            InitializeComponent();

            DataContext = Model = new SettingsModel(sidebar);

            Owner = sidebar;
            ShowDialog();
        }
        private void CloseButton_Click(object sender, RoutedEventArgs e)
        {
            if (Model.IsChanged)
            {
                Sidebar _sidebar = (Application.Current as App).GetSidebar;

                if (_sidebar != null)
                {
                    DataContext = Model = new SettingsModel(_sidebar);
                    return;
                }
            }

            Close();
        }
        public Settings()
        {
            InitializeComponent();

            DataContext = Model = new SettingsModel();
        }