ShrlAlgoToolkit/WPFDark/Controls/Converters/TreeListViewItemMarginConverter.cs

using System;
using System.Globalization;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;

using WPFDark.Internals;

namespace WPFDark.Controls.Converters
{
    public class TreeListViewItemMarginConverter : IValueConverter
    {
        public double Length { get; set; }
        public bool IsFirstColumn { get; set; }

        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (!(value is TreeViewItem item))
                return new Thickness(0);

            var right = Length * (item.GetDepth() + 1.0);
            var left = IsFirstColumn ? -6.0 : right * -1.0;

            return new Thickness(left, 0, right, 0);
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }
}