public SecondPage()
        {
            InitializeComponent();

            viewModel           = new SecondPageViewModel();
            this.BindingContext = viewModel;

            ItemPickList.SetBinding(Picker.ItemsSourceProperty, new Binding {
                Path = "ColorPicerData"
            });
            ItemPickList.SetBinding(Picker.SelectedItemProperty, new Binding {
                Path = "SelectedItem"
            });
        }
        private void DataPickList_SelectedIndexChanged(object sender, EventArgs e)
        {
            Picker picker = sender as Picker;

            if (picker.SelectedItem.Equals("alphabet"))
            {
                ItemPickList.SetBinding(Picker.ItemsSourceProperty, new Binding {
                    Path = "AlphaBetData"
                });
                ItemPickList.SetBinding(Picker.SelectedItemProperty, new Binding {
                    Path = "AlphaBetSelectedItem"
                });
            }
            else
            {
                ItemPickList.SetBinding(Picker.ItemsSourceProperty, new Binding {
                    Path = "ColorPicerData"
                });
                ItemPickList.SetBinding(Picker.SelectedItemProperty, new Binding {
                    Path = "SelectedItem"
                });
            }
        }