WPF DataGrid RowDetailsTemplate RowDetailsVisibilityMode="VisibleWhenSelected"

 <Grid>
     <DataGrid ItemsSource="{StaticResource booksData}"
               EnableColumnVirtualization="True"
               EnableRowVirtualization="True"
               RowDetailsVisibilityMode="VisibleWhenSelected">
         <DataGrid.RowDetailsTemplate>
             <DataTemplate>
                 <Viewbox>
                     <Image Source="{Binding ImgUrl}" Width="200" Height="500"
                            HorizontalAlignment="Left"
                            VerticalAlignment="Stretch"/>
                 </Viewbox>
             </DataTemplate>
         </DataGrid.RowDetailsTemplate>
     </DataGrid>
 </Grid>

//xaml
<Window x:Class="WpfApp398.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:WpfApp398"
        mc:Ignorable="d"
        WindowState="Maximized"
        Title="MainWindow" Height="450" Width="800">
    <Window.Resources>
        <local:BooksData x:Key="booksData"/>
    </Window.Resources>
    <Grid>
        <DataGrid ItemsSource="{StaticResource booksData}"
                  EnableColumnVirtualization="True"
                  EnableRowVirtualization="True"
                  RowDetailsVisibilityMode="VisibleWhenSelected">
            <DataGrid.RowDetailsTemplate>
                <DataTemplate>
                    <Viewbox>
                        <Image Source="{Binding ImgUrl}" Width="200" Height="500"
                               HorizontalAlignment="Left"
                               VerticalAlignment="Stretch"/>
                    </Viewbox>
                </DataTemplate>
            </DataGrid.RowDetailsTemplate>
        </DataGrid>
    </Grid>
</Window>


//cs
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
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;
using System.IO;

namespace WpfApp398
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }
    }

    public class BooksData:ObservableCollection<Book>
    {
        public BooksData()
        {
            var imgsList = Directory.GetFiles(@"../../Images");
            if(imgsList!=null && imgsList.Any())
            {
                int imgsCount = imgsList.Count();
                for (int i = 1; i <= 1000000; i++)
                {
                    this.Add(new Book()
                    {
                        Id = i,
                        Name = $"Name_{i}",
                        ISBN = $"ISBN_{i}",
                        ImgUrl = imgsList[i%imgsCount]
                    });
                }
            }
        }
    }

    public class Book
    {
        public int Id { get; set; }

        public string Name { get; set; }

        public string ISBN { get; set; }

        public string ImgUrl { get; set; }
    }
}