WPF Click Window show XY coordinates in MVVM via InvokeCommandAction of behavior

1.Install Microsoft.Xaml.Behaviors.Wpf

2.

 <behavior:Interaction.Triggers>
     <behavior:EventTrigger EventName="MouseDown">
         <behavior:InvokeCommandAction 
             Command="{Binding ClickCommand}"
             CommandParameter="{Binding RelativeSource={RelativeSource Mode=FindAncestor,
             AncestorType={x:Type Window}}}"/>
     </behavior:EventTrigger>
 </behavior:Interaction.Triggers>


//cs
private void InitCommands()
{
    ClickCommand = new DelCmd(ClickCommandExecuted);
}

private void ClickCommandExecuted(object obj)
{
     var win = obj as Window;
    if (win != null)
    {
        var pt = Mouse.GetPosition(win);
        MessageBox.Show($"{pt.X},{pt.Y}", "Clicked Position!");
    }
}

public DelCmd ClickCommand { get; set; }

 xaml

//xaml
<Window x:Class="WpfApp1.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:WpfApp1"
        xmlns:behavior="http://schemas.microsoft.com/xaml/behaviors"
        mc:Ignorable="d"
        WindowState="Maximized"
        Title="MainWindow" Height="450" Width="800">
    <behavior:Interaction.Triggers>
        <behavior:EventTrigger EventName="MouseDown">
            <behavior:InvokeCommandAction 
                Command="{Binding ClickCommand}"
                CommandParameter="{Binding RelativeSource={RelativeSource Mode=FindAncestor,
                AncestorType={x:Type Window}}}"/>
        </behavior:EventTrigger>
    </behavior:Interaction.Triggers>
    <Window.Resources>
        <SolidColorBrush Color="Cyan" x:Key="imgBg"/>
    </Window.Resources>
    <Window.DataContext>
        <local:BookVM/>
    </Window.DataContext>     
    <Grid>
        <Image Source="/Images/1.jpg" RenderOptions.BitmapScalingMode="Fant"/>
    </Grid>
</Window>



//cs
using System;
using System.Collections.Generic;
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;

namespace WpfApp1
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }
    }

    public class BookVM
    {
        public BookVM()
        {
            InitCommands();
        }

        private void InitCommands()
        {
            ClickCommand = new DelCmd(ClickCommandExecuted);
        }

        private void ClickCommandExecuted(object obj)
        {
             var win = obj as Window;
            if (win != null)
            {
                var pt = Mouse.GetPosition(win);
                MessageBox.Show($"{pt.X},{pt.Y}", "Clicked Position!");
            }
        }

        public DelCmd ClickCommand { get; set; }
    }

    public class DelCmd : ICommand
    {
        public event EventHandler CanExecuteChanged
        {
            add
            {
                CommandManager.RequerySuggested += value;
            }
            remove
            {
                CommandManager.RequerySuggested -= value;
            }
        }


        private Action<object> execute;

        private Predicate<object> canExecute;

        public DelCmd(Action<object> executeValue, Predicate<object> canExecuteValue)
        {
            execute = executeValue;
            canExecute = canExecuteValue;
        }

        public DelCmd(Action<object> executeValue) : this(executeValue, null)
        {
        }

        public bool CanExecute(object parameter)
        {
            if (canExecute == null)
            {
                return true;
            }
            return canExecute(parameter);
        }

        public void Execute(object parameter)
        {
            execute(parameter);
        }
    }
}