WPF中ListView添加网格线

[ContentProperty("Target")]
    public class GridLineDecorator : FrameworkElement
    {
        private ListView _target;
        private DrawingVisual _gridLinesVisual = new DrawingVisual();
        private GridViewHeaderRowPresenter _headerRowPresenter = null;

        public GridLineDecorator()
        {
            this.AddVisualChild(_gridLinesVisual);
            this.AddHandler(ScrollViewer.ScrollChangedEvent, new RoutedEventHandler(OnScrollChanged));
        }

        #region GridLineBrush

        /// <summary>  
        /// GridLineBrush Dependency Property  
        /// </summary>  
        public static readonly DependencyProperty GridLineBrushProperty =
            DependencyProperty.Register("GridLineBrush", typeof(Brush), typeof(GridLineDecorator),
                new FrameworkPropertyMetadata(Brushes.LightGray,
                    new PropertyChangedCallback(OnGridLineBrushChanged)));

        /// <summary>  
        /// Gets or sets the GridLineBrush property.  This dependency property   
        /// indicates ....  
        /// </summary>  
        public Brush GridLineBrush
        {
            get { return (Brush)GetValue(GridLineBrushProperty); }
            set { SetValue(GridLineBrushProperty, value); }
        }

        /// <summary>  
        /// Handles changes to the GridLineBrush property.  
        /// </summary>  
        private static void OnGridLineBrushChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            ((GridLineDecorator)d).OnGridLineBrushChanged(e);
        }

        /// <summary>  
        /// Provides derived classes an opportunity to handle changes to the GridLineBrush property.  
        /// </summary>  
        protected virtual void OnGridLineBrushChanged(DependencyPropertyChangedEventArgs e)
        {
            DrawGridLines();
        }

        #endregion

        #region Target

        public ListView Target
        {
            get { return _target; }
            set
            {
                if (_target != value)
                {
                    if (_target != null) Detach();
                    RemoveVisualChild(_target);
                    RemoveLogicalChild(_target);

                    _target = value;
                    AddVisualChild(_target);
                    AddLogicalChild(_target);
                 
                    if (_target != null) Attach();

                    InvalidateMeasure();
                }
            }
        }

        private void GetGridViewHeaderPresenter()
        {
            if (Target == null)
            {
                _headerRowPresenter = null;
                return;
            }
            _headerRowPresenter = Target.GetDesendentChild<GridViewHeaderRowPresenter>();
        }

        #endregion

        #region DrawGridLines

        private void DrawGridLines()
        {
            if (Target == null) return;
            if (_headerRowPresenter == null) return;

            var itemCount = Target.Items.Count;
            if (itemCount == 0) return;

            var gridView = Target.View as GridView;
            if (gridView == null) return;
       
            // 获取drawingContext  
            var drawingContext = _gridLinesVisual.RenderOpen();
            var startPoint = new Point(0, 0);

            // 为了对齐到像素的计算参数，否则就会看到有些线是模糊的  
            var dpiFactor = this.GetDpiFactor();
            var pen = new Pen(this.GridLineBrush, 1 * dpiFactor);
            var halfPenWidth = pen.Thickness / 2;
            var guidelines = new GuidelineSet();

            // 计算表头的偏移量和大小  
            var headerOffset = _headerRowPresenter.TranslatePoint(startPoint, this);
            var headerSize = _headerRowPresenter.RenderSize;
            var headerBottomY = headerOffset.Y + headerSize.Height;

            // 计算ScrollViewer的可视区域大小  
            var item0 = _target.ItemContainerGenerator.ContainerFromIndex(0);
            if (item0 == null) return;

            var scrollViewer = item0.GetAncestor<ScrollViewer>();
            if (scrollViewer == null) return;

            var contentElement = scrollViewer.Content as UIElement;
            var maxLineX = scrollViewer.ViewportWidth;
            var maxLineY = headerBottomY + contentElement.RenderSize.Height;

            var vLineY = 0.0;

            // 画横线  
            for (int i = 0; i < itemCount; i++)
            {
                var item = Target.ItemContainerGenerator.ContainerFromIndex(i) as ListViewItem;
                if (item != null)
                {
                    var renderSize = item.RenderSize;
                    var offset = item.TranslatePoint(startPoint, this);

                    var hLineX1 = offset.X;
                    var hLineX2 = offset.X + renderSize.Width;
                    var hLineY = offset.Y + renderSize.Height;
                    vLineY = hLineY;

                    // 小于视图起始位置的不绘制  
                    if (hLineY <= headerBottomY) continue;

                    // 大于视图结束位置之后的不绘制  
                    if (hLineY > maxLineY) break;

                    // 如果大于横向宽度，取横向宽度  
                    if (hLineX2 > maxLineX) hLineX2 = maxLineX;

                    // 加入参考线，对齐到像素  
                    guidelines.GuidelinesY.Add(hLineY + halfPenWidth);
                    drawingContext.PushGuidelineSet(guidelines);
                    drawingContext.DrawLine(pen, new Point(hLineX1, hLineY), new Point(hLineX2, hLineY));
                    drawingContext.Pop();
                }
            }

            
             //画竖线  
            var columns = gridView.Columns;
            var vLineX = headerOffset.X;
            if (vLineY > maxLineY) vLineY = maxLineY;

            foreach (var column in columns)
            {
                var columnWidth = column.GetColumnWidth();
                vLineX += columnWidth;

                if (vLineX > maxLineX) break;

                //加入参考线，对齐到像素  
                guidelines.GuidelinesX.Add(vLineX + halfPenWidth);
                drawingContext.PushGuidelineSet(guidelines);
                drawingContext.DrawLine(pen, new Point(vLineX, headerBottomY), new Point(vLineX, vLineY));
                drawingContext.Pop();
            }
           

            drawingContext.Close();
        }

        #endregion

        #region Overrides to show Target and grid lines

        protected override int VisualChildrenCount
        {
            get { return Target == null ? 1 : 2; }
        }

        protected override System.Collections.IEnumerator LogicalChildren
        {
            get { yield return Target; }
        }

        protected override Visual GetVisualChild(int index)
        {
            if (index == 0) return _target;
            if (index == 1) return _gridLinesVisual;
            throw new IndexOutOfRangeException(string.Format("Index of visual child '{0}' is out of range", index));
        }

        protected override Size MeasureOverride(Size availableSize)
        {
            if (Target != null)
            {
                Target.Measure(availableSize);
                return Target.DesiredSize;
            }

            return base.MeasureOverride(availableSize);
        }

        protected override Size ArrangeOverride(Size finalSize)
        {
            if (Target != null)
                Target.Arrange(new Rect(new Point(0, 0), finalSize));

            return base.ArrangeOverride(finalSize);
        }

        #endregion

        #region Handle Events

        private void Attach()
        {
            _target.Loaded += OnTargetLoaded;
            _target.Unloaded += OnTargetUnloaded;
            _target.SizeChanged += OnTargetSizeChanged;
            _target.DragEnter += _target_DragEnter;
        }

        void _target_DragEnter(object sender, DragEventArgs e)
        {
            DrawGridLines();
        }


        private void Detach()
        {
            _target.Loaded -= OnTargetLoaded;
            _target.Unloaded -= OnTargetUnloaded;
            _target.SizeChanged -= OnTargetSizeChanged;
        }

        private void OnTargetLoaded(object sender, RoutedEventArgs e)
        {
            if (_headerRowPresenter == null)
                GetGridViewHeaderPresenter();
            DrawGridLines();
        }

        private void OnTargetUnloaded(object sender, RoutedEventArgs e)
        {
            DrawGridLines();
        }

        private void OnTargetSizeChanged(object sender, SizeChangedEventArgs e)
        {
            DrawGridLines();
        }

        private void OnScrollChanged(object sender, RoutedEventArgs e)
        {
            DrawGridLines();
        }
        #endregion  
    }

　　GridViewColumnHelper

internal  static class GridViewColumnHelper
    {
        private static PropertyInfo DesiredWidthProperty =
           typeof(GridViewColumn).GetProperty("DesiredWidth", BindingFlags.NonPublic | BindingFlags.Instance);

        public static double GetColumnWidth(this GridViewColumn column)
        {
            return (double.IsNaN(column.Width)) ? (double)DesiredWidthProperty.GetValue(column, null) : column.Width;
        }  
    }

　　

VisualService

public static class VisualService
    {
        public static double GetDpiFactor(this Visual target)
        {
            var source = PresentationSource.FromVisual(target);
            return source == null ? 1.0 : 1 / source.CompositionTarget.TransformToDevice.M11;
        }

        public static T GetAncestor<T>(this DependencyObject target)
            where T : DependencyObject
        {
            var parent = VisualTreeHelper.GetParent(target);
            if (parent is T)
                return (T)parent;

            if (parent != null)
                return parent.GetAncestor<T>();

            return null;
        }

        public static T GetDesendentChild<T>(this DependencyObject target)
            where T : DependencyObject
        {
            var childCount = VisualTreeHelper.GetChildrenCount(target);
            if (childCount == 0) return null;

            for (int i = 0; i < childCount; i++)
            {
                var current = VisualTreeHelper.GetChild(target, i);
                if (current is T)
                    return (T)current;

                var desendent = current.GetDesendentChild<T>();
                if (desendent != null)
                    return desendent;
            }
            return null;
        }
    }  

    <listViewWithLines:GridLineDecorator GridLineBrush="CornflowerBlue"   >
            <ListView >
                ...
            </ListView>
        </listViewWithLines:GridLineDecorator>