Avalonia/samples/ControlCatalog/Pages/MenuPage.xaml.cs

using System;
using System.Collections.Generic;
using System.Reactive;
using System.Threading.Tasks;
using System.Windows.Input;
using Avalonia.Controls;
using Avalonia.Markup.Xaml;
using ControlCatalog.ViewModels;

namespace ControlCatalog.Pages
{
    public class MenuPage : UserControl
    {
        public MenuPage()
        {
            this.InitializeComponent();
            DataContext = new MenuPageViewModel();
        }

        private void InitializeComponent()
        {
            AvaloniaXamlLoader.Load(this);
        }
        
        private MenuPageViewModel? _model;
        protected override void OnDataContextChanged(EventArgs e)
        {
            if (_model != null)
                _model.View = null;
            _model  = DataContext as MenuPageViewModel;
            if (_model != null)
                _model.View = this;

            base.OnDataContextChanged(e);
        }
        
    }
}