WPF viewmodel retrieve matched view /window

private Window? GetWindow()
{
    foreach (Window win in Application.Current.Windows)
    {
        if (win.DataContext==this)
        {
            return win;
        }
    }
    return null;
}

 

 

Install-Package CommunityToolkit.mvvm;
Install-Package Micorosoft.Extensions.DependencyInjection;

 

 

 

//app.xaml
<Application x:Class="WpfApp28.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:local="clr-namespace:WpfApp28">
    <Application.Resources>
         
    </Application.Resources>
</Application>


//app.xaml.cs
using Microsoft.Extensions.DependencyInjection;
using System.Configuration;
using System.Data;
using System.Windows;

namespace WpfApp28
{
    /// <summary>
    /// Interaction logic for App.xaml
    /// </summary>
    public partial class App : Application
    {
        ServiceProvider serviceProvider;
        protected override void OnStartup(StartupEventArgs e)
        {
            base.OnStartup(e);

            var services = new ServiceCollection();
            ConfigureServices(services);

            serviceProvider = services.BuildServiceProvider();
            var mainWin = serviceProvider.GetRequiredService<MainWindow>();
            mainWin?.Show();
        }

        private static void ConfigureServices(ServiceCollection services)
        {
            services.AddSingleton<IIDService, IDService>();
            services.AddSingleton<INameService, NameService>();
            services.AddSingleton<IISBNService, ISBNService>();
            services.AddSingleton<MainVM>();
            services.AddSingleton<MainWindow>();
            
        }

        protected override void OnExit(ExitEventArgs e)
        {
            base.OnExit(e);
            serviceProvider?.Dispose();
        }
    }

}


//mainwindow.xaml
<Window x:Class="WpfApp28.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp28"
        WindowState="Maximized"
        mc:Ignorable="d"
        Title="{Binding StatusMsg,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}" Height="450" Width="800">
    <Grid>
        <ListBox
                 ItemsSource="{Binding BooksCollection,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
                 VirtualizingPanel.IsVirtualizing="True"
                 VirtualizingPanel.VirtualizationMode="Recycling"
                 ScrollViewer.IsDeferredScrollingEnabled="True"
                 >
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <Grid       
                                Width="{Binding DataContext.GridWidth,RelativeSource={RelativeSource AncestorType=Window}}"
                                Height="{Binding DataContext.GridHeight,RelativeSource={RelativeSource AncestorType=Window}}">
                        <Grid.Background>
                            <ImageBrush ImageSource="{Binding ImgSource}"/>
                        </Grid.Background>
                        <Grid.Resources>
                            <Style TargetType="TextBlock">
                                <Setter Property="FontSize" Value="30"/>
                                <Setter Property="HorizontalAlignment" Value="Center"/>
                                <Setter Property="VerticalAlignment" Value="Center"/>
                                <Style.Triggers>
                                    <Trigger Property="IsMouseOver" Value="True">
                                        <Setter Property="FontSize" Value="50"/>
                                        <Setter Property="Foreground" Value="Red"/>
                                    </Trigger>
                                </Style.Triggers>
                            </Style>
                        </Grid.Resources>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition/>
                            <ColumnDefinition/>
                        </Grid.ColumnDefinitions>
                        <Grid.RowDefinitions>
                            <RowDefinition/>
                            <RowDefinition/>
                        </Grid.RowDefinitions>
                        <TextBlock Text="{Binding Id}" Grid.Column="0" Grid.Row="0"/>
                        <TextBlock Text="{Binding Name}" Grid.Column="1" Grid.Row="0"/>
                        <TextBlock Text="{Binding ISBN}" Grid.Column="0" Grid.ColumnSpan="2" Grid.Row="1"/>
                    </Grid>
                </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>         
    </Grid>
</Window>


//window.xaml.cs
using CommunityToolkit.Mvvm.ComponentModel;
using System.Collections.ObjectModel;
using System.Diagnostics;
using System.IO;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace WpfApp28
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        public MainWindow(MainVM vm)
        {
            InitializeComponent();
            this.DataContext=vm;
            this.SizeChanged+=MainWindow_SizeChanged;
            this.Loaded+=async (s, e) =>
            {
                await LoadDataAsync();
            };
        }

        private async Task LoadDataAsync()
        {
            if (DataContext is MainVM vm)
            {
                await vm.InitDataAsync();
            }
        }

        private void MainWindow_SizeChanged(object sender, SizeChangedEventArgs e)
        {
            if (DataContext is MainVM vm)
            {
                var fe = this.Content as FrameworkElement;
                if (fe==null)
                {
                    return;
                }
                vm.GridWidth=fe.ActualWidth;
                vm.GridHeight=fe.ActualHeight/2;
            }
        }
    }

    public partial class MainVM : ObservableObject
    {
        IIDService idService;
        INameService nameService;
        IISBNService isbnService;
        private Stopwatch watch;
        public MainVM(IIDService idServiceValue,
            INameService nameServiceValue,
            IISBNService isbnServiceValue)
        {
            idService=idServiceValue;
            nameService=nameServiceValue;
            isbnService=isbnServiceValue;
            watch=Stopwatch.StartNew();

        }

        private void InitVisualTreesList()
        {
            VisualChildrenCollection=new ObservableCollection<string>();
            Window mainWin = GetWindow();
            if (mainWin!=null)
            {
                var visualsList = GetVisualChildren<Visual>(mainWin);
                foreach (var visual in visualsList)
                {
                    VisualChildrenCollection.Add(visual.GetType().Name);
                }
            }

            string visualChildrenStr = string.Join("\n", VisualChildrenCollection.ToArray());
            Debug.WriteLine($"Visual Tree children:\n{visualChildrenStr}\n\n\n");
        }

        public async Task InitDataAsync()
        {
            string imgDir = @"../../../Images";
            if (!Directory.Exists(imgDir))
            {
                return;
            }

            var imgs = Directory.GetFiles(imgDir);
            if (imgs==null ||!imgs.Any())
            {
                return;
            }

            int imgsCount = imgs.Count();
            BooksCollection=new ObservableCollection<Book>();
            List<Book> booksList = new List<Book>();

            await Task.Run(async () =>
            {
                for (int i = 0; i<1000001; i++)
                {
                    booksList.Add(new Book()
                    {
                        Id=idService.GetID(),
                        Name=nameService.GetName(),
                        ISBN=isbnService.GetISBN(),
                        ImgSource=GetImgSourceViaUrl(imgs[i%imgsCount])
                    });

                    if (i<1000&& i%100==0)
                    {
                        await PopulateBooksCollectionAsync(booksList);
                    }
                    else if (i>=1000 && i%1000000==0)
                    {
                        await PopulateBooksCollectionAsync(booksList);
                    }
                }

                if (booksList.Any())
                {
                    await PopulateBooksCollectionAsync(booksList);
                }
            });

            InitVisualTreesList();

            InitLogicalTreesList();
        }

        private void InitLogicalTreesList()
        {
            Window mainWin = GetWindow();
            var logicalChildren = GetAllLogicalChildren(mainWin);
            string logicalTreesStr = string.Join("\n", logicalChildren.Select(x => x.GetType().Name));
            Debug.WriteLine(logicalTreesStr);
        }

        private ImageSource GetImgSourceViaUrl(string imgUrl)
        {
            BitmapImage bmi = new BitmapImage();
            bmi.BeginInit();
            bmi.UriSource=new Uri(imgUrl, UriKind.RelativeOrAbsolute);
            bmi.CacheOption=BitmapCacheOption.OnDemand;
            bmi.EndInit();
            bmi.Freeze();
            return bmi;
        }

        private async Task PopulateBooksCollectionAsync(List<Book> booksList)
        {
            var tempList = booksList.ToList();
            booksList.Clear();
            await Application.Current.Dispatcher.InvokeAsync(() =>
            {
                foreach (var bk in tempList)
                {
                    BooksCollection.Add(bk);
                }
                StatusMsg=$"Loaded {BooksCollection.Count} items,{GetMemory()},{GetTimeCost()}";
            }, System.Windows.Threading.DispatcherPriority.Background);
        }

        private string GetMemory()
        {
            var procMemory = Process.GetCurrentProcess().PrivateMemorySize64/1024.0d/1024.0d;
            return $"Memory:{procMemory.ToString("#,##0.00")} M";
        }

        private string GetTimeCost()
        {
            return $"Time cost: {watch.Elapsed.TotalSeconds} seconds";
        }

        private static IEnumerable<T> GetVisualChildren<T>(DependencyObject parent) where T : DependencyObject
        {
            if (parent == null)
            {
                yield break;
            }

            int childrenCount = VisualTreeHelper.GetChildrenCount(parent);
            for (int i = 0; i<childrenCount; i++)
            {
                DependencyObject child = VisualTreeHelper.GetChild(parent, i);
                if (child is T tChild)
                {
                    yield return tChild;
                }

                foreach (var descedant in GetVisualChildren<T>(child))
                {
                    yield return descedant;
                }
            }
        }

        public static IEnumerable<DependencyObject> GetAllLogicalChildren(DependencyObject parent)
        {
            if (parent == null)
            {
                yield break;
            }

            foreach (var child in LogicalTreeHelper.GetChildren(parent))
            {
                if (child is DependencyObject depChild)
                {
                    yield return depChild;

                    // Recurse down into this child's children
                    foreach (var descendant in GetAllLogicalChildren(depChild))
                    {
                        yield return descendant;
                    }
                }
            }
        }

        private Window? GetWindow()
        {
            foreach (Window win in Application.Current.Windows)
            {
                if (win.DataContext==this)
                {
                    return win;
                }
            }
            return null;
        }


        [ObservableProperty]
        private double gridWidth;

        [ObservableProperty]
        private double gridHeight;

        [ObservableProperty]
        private ObservableCollection<Book> booksCollection;

        [ObservableProperty]
        private string statusMsg;

        [ObservableProperty]
        private ObservableCollection<string> visualChildrenCollection;
    }

    public class Book
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public string ISBN { get; set; }
        public ImageSource ImgSource { get; set; }
    }


    public interface IIDService
    {
        int GetID();
    }

    public class IDService : IIDService
    {
        int id = 0;

        public int GetID()
        {
            return Interlocked.Increment(ref id);
        }
    }

    public interface INameService
    {
        string GetName();
    }

    public class NameService : INameService
    {
        int idx = 0;
        public string GetName()
        {
            return $"Name_{Interlocked.Increment(ref idx)}";
        }
    }

    public interface IISBNService
    {
        string GetISBN();
    }

    public class ISBNService : IISBNService
    {
        int idx = 0;
        public string GetISBN()
        {
            return $"ISBN_{Interlocked.Increment(ref idx)}_{Guid.NewGuid():N}";
        }
    }
}