Jak mogę zmienić usuwanie przy użyciu menu kontekstowego oraz wzorca MVVM?

Cześć chciałbym użyć commond do usuwania i wzorca MVVM

using System;
using System.Collections.Generic;

namespace TestApp
{
    public class GuidModel
    {
        public Guid Guid { get; set; }

        public string Text
        {
            get
            {
                return Guid.ToString(); 
            }
            set
            {
                if (Guid.ToString() != value)
                {
                    Guid = Guid.Parse(value);
                }
            }
        }

        public GuidModel(Guid guid)
        {
            Guid = guid;
        }
    }
}

<?xml version="1.0" encoding="UTF-8"?>
<d:ExtendedContentPage xmlns:d="clr-namespace:TestApp;assembly=TestApp"
	xmlns="http://xamarin.com/schemas/2014/forms" xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml" 
	x:Class="TestApp.GuidPage" BackgroundColor="Gray" >
	<ContentPage.Content>
    <Grid>
	<ListView x:Name="GuidsView" ItemsSource="{Binding GuidItems}" SelectedItem="{Binding GuidItem, Mode=TwoWay}">
	<ListView.ItemTemplate>
      <DataTemplate>
        <TextCell Text="{Binding Text}">
          <TextCell.ContextActions>
            <MenuItem Clicked="OnDelete" CommandParameter="{Binding .}" Text="Delete" />
          </TextCell.ContextActions>
        </TextCell>
      </DataTemplate>
    </ListView.ItemTemplate>
  </ListView>
 </Grid>
</ContentPage.Content>
</d:ExtendedContentPage>

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using Xamarin.Forms;

namespace TestApp
{
    public partial class GuidPage : ExtendedContentPage
    {
        private readonly GuidViewModel _viewModel = null;

        public GuidPage()
        {
            InitializeComponent();

            if (_viewModel == null)
            {
                _viewModel = new GuidViewModel(Navigation);
            }

            BindingContext = _viewModel;
        }

        private void OnDelete(object sender, EventArgs e)
        {
            var mi = ((MenuItem)sender);

            GuidModel guidToRemove = (GuidModel)mi.CommandParameter;

            _viewModel.GuidItemDelete(guidToRemove);
        }
    }
}

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Diagnostics;
using Xamarin.Forms;


namespace TestApp
{
    public class GuidViewModel : BaseViewModel
    {
        private ObservableCollection<GuidModel> _guidItems = null;
        public ObservableCollection<GuidModel> GuidItems
        {
            get
            {
                return _guidItems;
            }
            set
            {
                if (_guidItems != value)
                {
                    _guidItems = value;
                    OnPropertyChanged();
                }
            }
        }

        private GuidModel _guidItem = null;
        public GuidModel GuidItem
        {
            get
            {
                return _guidItem;
            }
            set
            {
                if (_guidItem != value)
                {
                    _guidItem = value;
                    OnPropertyChanged();
                }
            }
        }


        public GuidViewModel(INavigation navigation) : base(navigation)
        {
            GuidItems = new ObservableCollection<GuidModel>();

            PrepareGuidList();
        }

        private void PrepareGuidList()
        {
            for (int i = 0; i < 100; i++)
            {
                _guidItems.Add(new GuidModel(Guid.NewGuid()));
            }
        }

        public void GuidItemDelete(GuidModel guidToRemove)
        {
            if (guidToRemove != null)
            {
                _guidItems.Remove(guidToRemove);
            }
        }

        public override void RemoveHandlers()
        {
            throw new NotImplementedException();
        }
    }
}

  public abstract class BaseViewModel : BaseNotifyPropertyChanged
    {
        #region Events
        public delegate void NavigateFromDetailPageHandler(ContentPage page);
        public event NavigateFromDetailPageHandler NavigateFromDetailPageEvent;
        private void OnNavigateFromDetailPage(ContentPage page)
        {
            if (NavigateFromDetailPageEvent != null) NavigateFromDetailPageEvent(page);
        }
        #endregion

        #region Fields
        private INavigation _navigation;
        #endregion

        #region Properties
        private PageManager PageManagerInstance
        {
            get
            {
                return SingletonsManager.Instance.PageManagerInstance;
            }
        }
        #endregion

        #region Methods
        protected virtual void OnNavigatedFrom() { }

        public BaseViewModel(INavigation navigation)
        {
            _navigation = navigation;
        }

        public async Task NavigateToPage(ContentPage page, bool detailPage = false, bool removePrevious = false)
        {

            PageManagerInstance.CurrentPage = page;

            if (detailPage)
            {
                OnNavigateFromDetailPage(page);
            }
            else
            {
                await _navigation.PushAsync(page);
            }

            if (removePrevious)
            {
                int navigationPageCount = _navigation.NavigationStack.Count;
                if (navigationPageCount - 2 >= 0)
                {
                    _navigation.RemovePage(_navigation.NavigationStack[navigationPageCount - 2]);
                }
            }
        }


        public abstract void RemoveHandlers();
        #endregion
    }