public MainPage()
        {
            _mainInstance = this;
            InitializeComponent();

            BindingContext = new MainPagePullToRefreshViewModel();
        }
        public MainPage()
        {
            _mainInstance = this;
            InitializeComponent();

            BindingContext = new MainPagePullToRefreshViewModel();


            list.Add(new Personal()
            {
                name = "Alperen", surname = "Eker"
            });
            list.Add(new Personal()
            {
                name = "İsa", surname = "Irız"
            });

            listView.ItemsSource = list;
        }