WPF 4数据网格:显示&;隐藏列

WPF 4数据网格:显示&;隐藏列,wpf,xaml,wpfdatagrid,Wpf,Xaml,Wpfdatagrid,我正在尝试为DataGrid实现列选择器功能,如果我试图将列标题的内容定义为字符串以外的内容,就会遇到问题。下面是一个非常简化的示例,所有样式、视图模型、绑定等都已剥离 共有3列: 第一列使用字符串作为标题。 第二列尝试将标题内容设置为带有工具提示的标签。 第三列使用工具提示将标题内容设置为TextBlock 单击A列的“切换可见性”按钮可以正常工作。B列和C列的切换可见性按钮都会导致InvalidOperationException,消息为“指定的元素已经是另一个元素的逻辑子元素。请先断开连接

我正在尝试为DataGrid实现列选择器功能,如果我试图将列标题的内容定义为字符串以外的内容,就会遇到问题。下面是一个非常简化的示例,所有样式、视图模型、绑定等都已剥离

共有3列:

第一列使用字符串作为标题。 第二列尝试将标题内容设置为带有工具提示的标签。 第三列使用工具提示将标题内容设置为TextBlock

单击A列的“切换可见性”按钮可以正常工作。B列和C列的切换可见性按钮都会导致InvalidOperationException,消息为“指定的元素已经是另一个元素的逻辑子元素。请先断开连接。”


谢谢大家。

我认为如果您只使用
DataGridTemplateColumn.HeaderStyle
而不是
DataGridTemplateColumn.Header

作为c列的示例:

<DataGridTemplateColumn x:Name="colC" Width="40*" IsReadOnly="True" >
    <DataGridTemplateColumn.HeaderStyle>
        <Style TargetType="DataGridColumnHeader">
            <Setter Property="ContentTemplate">
                <Setter.Value>
                    <DataTemplate>
                        <TextBlock Text="Column C"  ToolTip="A short explanation of Column C "/>
                    </DataTemplate>
                </Setter.Value>
            </Setter>
        </Style>
    </DataGridTemplateColumn.HeaderStyle>
    <DataGridTemplateColumn.CellTemplate>
        <DataTemplate>
            <TextBlock  />
        </DataTemplate>
    </DataGridTemplateColumn.CellTemplate>
  </DataGridTemplateColumn>
</DataGridTemplateColumn.HeaderStyle>

当我在资源中定义了一个控件,并试图在多个控件的内容区域中使用它时,我曾经遇到过这个问题。这不起作用,因为控件只能属于一个父控件

相反,我需要定义一个包含我想要的控件的模板,并直接设置对象的模板而不是内容

你对@Gimno答案的评论让我觉得情况就是这样

尝试更改它,而不是直接在DataGrid.Header的内容中设置标签/文本框,将DataGrid.HeaderTemplate设置为包含标签或文本框的DataTemplate

编辑

下面是一些示例代码

<DataGridTemplateColumn x:Name="colB" Width="40*" IsReadOnly="True" >
    <DataGridTemplateColumn.HeaderTemplate>
        <DataTemplate>
            <Label Content="Column B" ToolTip="A short explanation of Column B"/>
        </DataTemplate>
    </DataGridTemplateColumn.HeaderTemplate>
    <DataGridTemplateColumn.CellTemplate>
        <DataTemplate>
            <TextBlock />
        </DataTemplate>
    </DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>

我喜欢CodePlex的列选择器解决方案:

我清理代码并删除不必要的代码:

using System;
using System.Collections.Generic;
using System.Configuration;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using System.Windows.Media;
using Microsoft.Xaml.Behaviors;

namespace Behaviors
{
    public class WpfDataGridConfigurationBehavior : Behavior<DependencyObject>
    {

        #region "public Properties"


        public bool DontPersistVisibleColumns { get; set; }
        public bool DontPersistColumnsOrder { get; set; }

        public string ContextMenuChoices { get; set; } = "Alphabetical Menu,Show All Columns";

        public string DataGridName { get; set; }

        #endregion "public Properties"

        #region "private Properties"

        private DataGrid dataGrid;

        private ContextMenu theContextMenu; // Context Menu for the field chooser.

        private string AllColumnsHeaders { get; set; }
        private string AllColumnDisplayIndexes { get; set; }

        private int nBaseItems = 5;
        private MenuItem mnuAlpha;
        private MenuItem mnuShowAll;

        #endregion "Private Properties"

        protected override void OnAttached()
        {
            base.OnAttached();

            dataGrid = this.AssociatedObject as DataGrid;
            if (DataGridName == null) DataGridName = dataGrid.Name;

            ContextMenu_BuildStaticMenu();

            dataGrid.Loaded += (sender, e) => { DataGrid_Loaded(); };
            dataGrid.AutoGeneratedColumns += DataGrid_AutoGeneratedColumns;

            dataGrid.ColumnReordered += (sender, e) => { DataGrid_ColumnReordered(sender); };

            dataGrid.ContextMenuOpening += (sender, e) => { DataGrid_ContextMenuOpening(e); };

            dataGrid.LoadingRow += (sender, e) => { e.Row.Header = (e.Row.GetIndex() + 1).ToString(); };

            dataGrid.RowHeaderWidth = 0;
            var ns = new Style(typeof(DataGridRowHeader)) { BasedOn = dataGrid.RowHeaderStyle };
            ns.Setters.Add(new Setter(Control.FontWeightProperty, FontWeights.Bold));
            ns.Setters.Add(new Setter(Control.FontSizeProperty, 11.0));
            ns.Setters.Add(new Setter(Control.PaddingProperty, new Thickness(4, 0, 4, 0)));
            dataGrid.RowHeaderStyle = ns;
        }

        private void DataGrid_AutoGeneratedColumns(object sender, EventArgs e)
        {
            DataGrid_Loaded();
        }


        #region "DataGrid Events"


        private void DataGrid_ContextMenuOpening(ContextMenuEventArgs e)
        {
            var dep = (DependencyObject)e.OriginalSource;

            // iteratively traverse the visual tree
            while ((dep != null) && !(dep is DataGridCell) && !(dep is DataGridColumnHeader))
                dep = VisualTreeHelper.GetParent(dep);

            if (dep == null)
                return;

            if (dep is DataGridColumnHeader)
            {
                // do something
            }

            if (dep is DataGridCell)
            {
                // navigate further up the tree
                while ((dep != null) && !(dep is DataGridRow))
                    dep = VisualTreeHelper.GetParent(dep);

                var row = dep as DataGridRow;

                dataGrid.ItemContainerGenerator.IndexFromContainer(row);
            }
        }

        private void DataGrid_ColumnReordered(object sender)
        {
            Settings_SaveDisplayIndexes(sender);

            ContextMenu_BuildMenu();
        }

        private void DataGrid_Loaded()
        {
            ContextMenu_BuildMenu(false);

            VisibleColumns_Initialize();
        }

        #endregion "DataGrid Events"

        #region "ContextMenu Methods and Events"

        private void ContextMenu_BuildStaticMenu()
        {
            theContextMenu = new ContextMenu { FontSize = 11, StaysOpen = true };

            mnuAlpha = new MenuItem
            {
                Header = ContextMenuChoices.Split(',')[0],
                FontWeight = FontWeights.Bold,
                IsCheckable = true,
                StaysOpenOnClick = true
            };
            mnuAlpha.Click += (sender, e) => { ContextMenu_BuildMenu(); };

            mnuShowAll = new MenuItem
            {
                Header = ContextMenuChoices.Split(',')[1],
                FontWeight = FontWeights.Bold,
                IsCheckable = true,
                StaysOpenOnClick = true
            };
            mnuShowAll.Checked += (sender, e) => { VisibleColumns = AllColumnsHeaders; };
            mnuShowAll.Click += (sender, e) =>
            {
                if (mnuShowAll.IsChecked == false) VisibleColumns_Initialize();
            };


            theContextMenu.Items.Add(mnuShowAll);
            theContextMenu.Items.Add(mnuAlpha);
        }

        private void ContextMenu_BuildMenu(bool pbRebuild = true)
        {
            for (int i = theContextMenu.Items.Count - 1; i > 0; i--)
                if (((MenuItem)theContextMenu.Items[i]).FontWeight != FontWeights.Bold)
                    theContextMenu.Items.Remove(theContextMenu.Items[i]);

            nBaseItems = theContextMenu.Items.Count;

            // Attach the context menu to the DataGrid ColumnHeaders
            var headersPresenter = WpfDataGridConfigurationBehaviorFinder.FindChild<DataGridColumnHeadersPresenter>(dataGrid);
            ContextMenuService.SetContextMenu(headersPresenter, theContextMenu);

            if (VisibleColumns == null)
                throw (new SettingsPropertyNotFoundException("User's VisibleColumns setting not found."));

            // Get the current column ordering from user.config

            if (DisplayIndexes == null)
                throw (new SettingsPropertyNotFoundException("User's DisplayIndexes setting not found."));

            AllColumnDisplayIndexes = DisplayIndexes;
            string[] colIndexes = AllColumnDisplayIndexes.Split(new[] { ';' }, StringSplitOptions.RemoveEmptyEntries);

            var dataGridColumns = dataGrid.Columns.OrderBy(x => x.DisplayIndex);

            // Sort the columns in display index order so menu header order matchs display column order
            if (pbRebuild == false)
                // Initially the datagrid column order is such that display indexes are the same as the col indexes
                if (colIndexes.Length > 0)
                    dataGridColumns = dataGrid.Columns.OrderBy(x => Convert.ToInt16(colIndexes[x.DisplayIndex]));

            if (mnuAlpha.IsChecked)
                dataGridColumns = dataGrid.Columns.OrderBy(x => x.Header.ToString());

            AllColumnsHeaders = "";
            foreach (var col in dataGridColumns)
            {
                // All column name to a list of all column headers for later use.
                AllColumnsHeaders = $"{col.Header.ToString().Replace("\n", " ").Replace("\r", " ")};{AllColumnsHeaders}";

                // Add new menu item in display order.
                ContextMenu_AddNewMenuItem(col);
            }

            string sTemp = VisibleColumns;
            VisibleColumns = null;
            VisibleColumns = sTemp;

        }

        private void ContextMenu_AddNewMenuItem(DataGridColumn col)
        {
            var menuItem = new MenuItem { Header = col.Header.ToString().Replace("\n", " ").Replace("\r", " "), StaysOpenOnClick = true };
            var saVisibleColumns = new List<string> { string.Empty };
            if (VisibleColumns != null)
            {
                saVisibleColumns = VisibleColumns.Split(new[] { ';' }, StringSplitOptions.RemoveEmptyEntries).ToList();
            }

            menuItem.IsChecked = (saVisibleColumns.Contains(menuItem.Header));
            menuItem.Click += (sender, e) => { ContextMenu_ColumnName_Click(sender); };

            theContextMenu.Items.Add(menuItem);
        }

        private void ContextMenu_ColumnName_Click(object sender)
        {
            var mi = sender as MenuItem;

            // Get the column name that was clicked
            string colName = mi.Header.ToString();


            // Capture new visible columns list
            Settings_SaveVisibleColumns(mi, colName);
        }

        #endregion "ContextMenu Methods and Events"

        #region "Settings Methods"

        private void Settings_SaveVisibleColumns(MenuItem mi, string colName)
        {
            if (theContextMenu.Items.Count - nBaseItems < dataGrid.Columns.Count)
                return;

            // Put the visible column names into an array
            var saVisibleColumns = VisibleColumns.Split(new char[] { ';' }, StringSplitOptions.RemoveEmptyEntries).ToList();
            if (saVisibleColumns != null && saVisibleColumns.Count > 0 &&
                saVisibleColumns[saVisibleColumns.Count - 1].StartsWith("-"))
                saVisibleColumns.RemoveAt(saVisibleColumns.Count - 1);

            // If the menu item is unchecked (column is not visible)
            if (!mi.IsChecked)
                // Make the column visible by adding its name to the Visible Columns list
                saVisibleColumns.Add(colName);

            else
            // Hide the column by removing its name from the VisibleColumns list
            if (saVisibleColumns.Contains(colName) && saVisibleColumns.Count > 1)
                saVisibleColumns.Remove(colName);

            VisibleColumns = string.Join(";", saVisibleColumns) + ";";
        }

        private void Settings_SaveDisplayIndexes(object sender)
        {
            // Capture the new column order
            AllColumnDisplayIndexes = "";
            foreach (DataGridColumn col in ((DataGrid)sender).Columns)
            {
                AllColumnDisplayIndexes +=
                    (AllColumnDisplayIndexes.Length > 0 ? ";" : "") + col.DisplayIndex;
            }

            DisplayIndexes = AllColumnDisplayIndexes;
        }

        #endregion "Settings Methods"

        #region DisplayIndexes (DependencyProperty)

        public string DisplayIndexes
        {
            get { return (string)GetValue(DisplayIndexesProperty); }
            set { SetValue(DisplayIndexesProperty, value); }
        }

        public static readonly DependencyProperty DisplayIndexesProperty =
            DependencyProperty.Register("DisplayIndexes", typeof(string), typeof(WpfDataGridConfigurationBehavior), new PropertyMetadata("", OnDisplayIndexesChanged));

        private static void OnDisplayIndexesChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            ((WpfDataGridConfigurationBehavior)d).DisplayIndexesChanged(e);
        }

        public void DisplayIndexesChanged(DependencyPropertyChangedEventArgs e)
        {
            // Persist the new column order
            if (dataGrid != null && !DontPersistColumnsOrder)
                Settings_Save(DataGridName + "DisplayIndexes", AllColumnDisplayIndexes);
        }

        #endregion "DisplayIndexes (DependencyProperty)"

        #region VisibleColumns (DependencyProperty)

        /// <summary>
        /// 
        /// Gets or sets a value indicating the names of columns 
        /// (as they appear in the column header) to be visible, seperated by a semicolon.
        /// 
        /// Columns whose names are not here will be hidden.
        /// </summary>

        public string VisibleColumns
        {
            get { return (string)GetValue(VisibleColumnsProperty); }
            set { SetValue(VisibleColumnsProperty, value); }
        }

        private void VisibleColumns_Initialize()
        {
            // Get saved VisibleColumns from app.config
            // Initialize VisibleColumns
            VisibleColumns = string.IsNullOrEmpty(VisibleColumns.Replace("\n", " ").Replace("\r", " ")) ? AllColumnsHeaders : VisibleColumns;
        }


        public static readonly DependencyProperty VisibleColumnsProperty =
            DependencyProperty.Register("VisibleColumns", typeof(string), typeof(WpfDataGridConfigurationBehavior), new PropertyMetadata("", OnVisibleColumnsChanged));

        private static void OnVisibleColumnsChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            ((WpfDataGridConfigurationBehavior)d).VisibleColumnsChanged(e);
        }



        /// <summary>
        /// 
        /// Updates the display
        /// 
        /// </summary>
        /// <param name="e"></param>

        public void VisibleColumnsChanged(DependencyPropertyChangedEventArgs e)
        {
            if (theContextMenu == null)
                return;

            if (e.NewValue != null)
            {
                var showTheseColumns = e.NewValue.ToString().Split(new[] { ';' }, StringSplitOptions.RemoveEmptyEntries);
                var saContextMenuVisibleItems = new List<string>();

                int iCol = 0;

                foreach (MenuItem menuItem in theContextMenu.Items)
                {
                    // Show/Hide the Context Menu item's checkmark.
                    if (menuItem.FontWeight == FontWeights.Bold) continue;

                    menuItem.IsChecked = showTheseColumns.Contains(menuItem.Header.ToString());
                    if (menuItem.IsChecked) saContextMenuVisibleItems.Add(menuItem.Header.ToString());

                    mnuShowAll.IsChecked = mnuShowAll.IsChecked && menuItem.IsChecked;

                    // Assign menu item's column's DisplayIndex in display order, (i.e. in menu item order), looking up each column by header name.)
                    if (mnuAlpha.IsChecked == false)
                        dataGrid.Columns.First(x => x.Header.ToString().Replace("\n", " ").Replace("\r", " ") == menuItem.Header.ToString()).DisplayIndex = iCol++;
                }

                // Show the columns
                foreach (var col in dataGrid.Columns)
                    col.Visibility =
                        showTheseColumns.Contains(col.Header.ToString().Replace("\n", " ").Replace("\r", " "))
                        && (saContextMenuVisibleItems.Contains(col.Header.ToString().Replace("\n", " ")
                            .Replace("\r", " ")))
                            ? Visibility.Visible
                            : Visibility.Collapsed;

                // Persist the new visible columns list

                if (dataGrid != null && !DontPersistVisibleColumns)
                    Settings_Save(DataGridName + "VisibleColumns", VisibleColumns);

            }
        }

        #endregion "VisibleColumns"

        public static void Settings_Save(string propertyName, string propertyValue)
        {
            foreach (SettingsPropertyValue property in Settings.Default.PropertyValues)
            {
                if (propertyName == property.Name)
                {
                    property.PropertyValue = propertyValue;
                    Settings.Default.Save();
                }
            }
        }

    }
    
     public static class WpfDataGridConfigurationBehaviorFinder
    {
        public static T FindChild<T>(DependencyObject depObj) where T : DependencyObject
        {
            // Confirm obj is valid. 
            if (depObj == null) return null;

            // success case
            if (depObj is T) return depObj as T;

            for (int i = 0; i < VisualTreeHelper.GetChildrenCount(depObj); i++)
            {
                T obj = FindChild<T>(VisualTreeHelper.GetChild(depObj, i));
                if (obj != null) return obj;
            }
            return null;
        }

        public interface IBreakVisualParenting
        {
            DependencyObject Parent { get; }
        }

        public static T LastVisualAncestorOfType<T>(this DependencyObject element) where T : DependencyObject
        {
            T item = null;

            var parent = VisualTreeHelper.GetParent(element);
            while (parent != null)
            {
                if (parent is T)
                    item = (T)parent;
                if (parent is IBreakVisualParenting)
                {
                    parent = ((IBreakVisualParenting)parent).Parent;
                }
                else
                    parent = VisualTreeHelper.GetParent(parent);
            }

            return item;
        }

    }
}
使用系统;
使用System.Collections.Generic;
使用系统配置;
使用System.Linq;
使用System.Windows;
使用System.Windows.Controls;
使用System.Windows.Controls.Primitives;
使用System.Windows.Media;
使用Microsoft.Xaml.Behaviors;
命名空间行为
{
公共类WpfDataGridConfigurationBehavior:行为
{
#区域“公共财产”
public bool DontPersistVisibleColumns{get;set;}
公共bool DontPersistColumnsOrder{get;set;}
公共字符串ContextMenuChoices{get;set;}=“字母菜单,显示所有列”;
公共字符串DataGridName{get;set;}
#endregion“公共财产”
#区域“私人财产”
私有数据网格;
私有上下文菜单上下文菜单;//字段选择器的上下文菜单。
私有字符串AllColumnsHeaders{get;set;}
私有字符串AllColumnDisplayIndexes{get;set;}
私人项目=5;
私人MenuItem mnuAlpha;
私人MenuItem mnuShowAll;
#endregion“私有财产”
受保护的覆盖无效附加()
{
base.onatached();
dataGrid=this.AssociatedObject作为dataGrid;
如果(DataGridName==null)DataGridName=dataGrid.Name;
ContextMenu_BuildStaticMenu();
dataGrid.Loaded+=(发送方,e)=>{dataGrid_Loaded();};
dataGrid.AutoGeneratedColumns+=dataGrid_AutoGeneratedColumns;
dataGrid.ColumnReordered+=(发送方,e)=>{dataGrid_ColumnReordered(发送方);};
dataGrid.ContextMenuOpening+=(发送方,e)=>{dataGrid_ContextMenuOpening(e);};
dataGrid.LoadingRow+=(发送方,e)=>{e.Row.Header=(e.Row.GetIndex()+1).ToString();};
dataGrid.RowHeaderWidth=0;
var ns=新样式(typeof(DataGridRowHeader)){BasedOn=dataGrid.RowHeaderStyle};
添加(新的Setter(Control.FontWeightProperty,FontWeights.Bold));
添加(新的Setter(Control.FontSizeProperty,11.0));
添加(新Setter(Control.PaddingProperty,新厚度(4,0,4,0));
dataGrid.RowHeaderStyle=ns;
}
私有void DataGrid_AutoGeneratedColumns(对象发送方,事件参数e)
{
DataGrid_已加载();
}
#区域“数据网格事件”
私有void DataGrid_ContextMenuOpening(ContextMenuEventArgs e)
{
var dep=(DependencyObject)e.OriginalSource;
//迭代遍历可视化树
而((dep!=null)&&&!(dep是DataGridCell)&&!(dep是DataGridColumnHeader))
dep=VisualTreeHelper.GetParent(dep);
if(dep==null)
返回;
if(dep是DataGridColumnHeader)
{
//做点什么
}
if(dep是DataGridCell)
{
//在树上进一步导航
而((dep!=null)&&!(dep是DataGridRow))
dep=VisualTreeHelper.GetParent(dep);
var row=dep作为DataGridRow;
dataGrid.ItemContainerGenerator.IndexFromContainer(行);
}
}
私有void DataGrid\u列重新排序(对象发送方)
{
设置\u保存显示索引(发送方);
ContextMenu_BuildMenu();
}
私有void DataGrid_加载()
{
ContextMenu_BuildMenu(false);
VisibleColumns_Initialize();
}
#endregion“数据网格事件”
#区域“上下文菜单方法和事件”
私有void ContextMenu_BuildStaticMenu()
{
ContextMenu=newcontextmenu{FontSize=11,StaysOpen=true};
mnuAlpha=新
<DataGridTemplateColumn x:Name="colB" Width="40*" IsReadOnly="True" >
    <DataGridTemplateColumn.HeaderTemplate>
        <DataTemplate>
            <Label Content="Column B" ToolTip="A short explanation of Column B"/>
        </DataTemplate>
    </DataGridTemplateColumn.HeaderTemplate>
    <DataGridTemplateColumn.CellTemplate>
        <DataTemplate>
            <TextBlock />
        </DataTemplate>
    </DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
using System;
using System.Collections.Generic;
using System.Configuration;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using System.Windows.Media;
using Microsoft.Xaml.Behaviors;

namespace Behaviors
{
    public class WpfDataGridConfigurationBehavior : Behavior<DependencyObject>
    {

        #region "public Properties"


        public bool DontPersistVisibleColumns { get; set; }
        public bool DontPersistColumnsOrder { get; set; }

        public string ContextMenuChoices { get; set; } = "Alphabetical Menu,Show All Columns";

        public string DataGridName { get; set; }

        #endregion "public Properties"

        #region "private Properties"

        private DataGrid dataGrid;

        private ContextMenu theContextMenu; // Context Menu for the field chooser.

        private string AllColumnsHeaders { get; set; }
        private string AllColumnDisplayIndexes { get; set; }

        private int nBaseItems = 5;
        private MenuItem mnuAlpha;
        private MenuItem mnuShowAll;

        #endregion "Private Properties"

        protected override void OnAttached()
        {
            base.OnAttached();

            dataGrid = this.AssociatedObject as DataGrid;
            if (DataGridName == null) DataGridName = dataGrid.Name;

            ContextMenu_BuildStaticMenu();

            dataGrid.Loaded += (sender, e) => { DataGrid_Loaded(); };
            dataGrid.AutoGeneratedColumns += DataGrid_AutoGeneratedColumns;

            dataGrid.ColumnReordered += (sender, e) => { DataGrid_ColumnReordered(sender); };

            dataGrid.ContextMenuOpening += (sender, e) => { DataGrid_ContextMenuOpening(e); };

            dataGrid.LoadingRow += (sender, e) => { e.Row.Header = (e.Row.GetIndex() + 1).ToString(); };

            dataGrid.RowHeaderWidth = 0;
            var ns = new Style(typeof(DataGridRowHeader)) { BasedOn = dataGrid.RowHeaderStyle };
            ns.Setters.Add(new Setter(Control.FontWeightProperty, FontWeights.Bold));
            ns.Setters.Add(new Setter(Control.FontSizeProperty, 11.0));
            ns.Setters.Add(new Setter(Control.PaddingProperty, new Thickness(4, 0, 4, 0)));
            dataGrid.RowHeaderStyle = ns;
        }

        private void DataGrid_AutoGeneratedColumns(object sender, EventArgs e)
        {
            DataGrid_Loaded();
        }


        #region "DataGrid Events"


        private void DataGrid_ContextMenuOpening(ContextMenuEventArgs e)
        {
            var dep = (DependencyObject)e.OriginalSource;

            // iteratively traverse the visual tree
            while ((dep != null) && !(dep is DataGridCell) && !(dep is DataGridColumnHeader))
                dep = VisualTreeHelper.GetParent(dep);

            if (dep == null)
                return;

            if (dep is DataGridColumnHeader)
            {
                // do something
            }

            if (dep is DataGridCell)
            {
                // navigate further up the tree
                while ((dep != null) && !(dep is DataGridRow))
                    dep = VisualTreeHelper.GetParent(dep);

                var row = dep as DataGridRow;

                dataGrid.ItemContainerGenerator.IndexFromContainer(row);
            }
        }

        private void DataGrid_ColumnReordered(object sender)
        {
            Settings_SaveDisplayIndexes(sender);

            ContextMenu_BuildMenu();
        }

        private void DataGrid_Loaded()
        {
            ContextMenu_BuildMenu(false);

            VisibleColumns_Initialize();
        }

        #endregion "DataGrid Events"

        #region "ContextMenu Methods and Events"

        private void ContextMenu_BuildStaticMenu()
        {
            theContextMenu = new ContextMenu { FontSize = 11, StaysOpen = true };

            mnuAlpha = new MenuItem
            {
                Header = ContextMenuChoices.Split(',')[0],
                FontWeight = FontWeights.Bold,
                IsCheckable = true,
                StaysOpenOnClick = true
            };
            mnuAlpha.Click += (sender, e) => { ContextMenu_BuildMenu(); };

            mnuShowAll = new MenuItem
            {
                Header = ContextMenuChoices.Split(',')[1],
                FontWeight = FontWeights.Bold,
                IsCheckable = true,
                StaysOpenOnClick = true
            };
            mnuShowAll.Checked += (sender, e) => { VisibleColumns = AllColumnsHeaders; };
            mnuShowAll.Click += (sender, e) =>
            {
                if (mnuShowAll.IsChecked == false) VisibleColumns_Initialize();
            };


            theContextMenu.Items.Add(mnuShowAll);
            theContextMenu.Items.Add(mnuAlpha);
        }

        private void ContextMenu_BuildMenu(bool pbRebuild = true)
        {
            for (int i = theContextMenu.Items.Count - 1; i > 0; i--)
                if (((MenuItem)theContextMenu.Items[i]).FontWeight != FontWeights.Bold)
                    theContextMenu.Items.Remove(theContextMenu.Items[i]);

            nBaseItems = theContextMenu.Items.Count;

            // Attach the context menu to the DataGrid ColumnHeaders
            var headersPresenter = WpfDataGridConfigurationBehaviorFinder.FindChild<DataGridColumnHeadersPresenter>(dataGrid);
            ContextMenuService.SetContextMenu(headersPresenter, theContextMenu);

            if (VisibleColumns == null)
                throw (new SettingsPropertyNotFoundException("User's VisibleColumns setting not found."));

            // Get the current column ordering from user.config

            if (DisplayIndexes == null)
                throw (new SettingsPropertyNotFoundException("User's DisplayIndexes setting not found."));

            AllColumnDisplayIndexes = DisplayIndexes;
            string[] colIndexes = AllColumnDisplayIndexes.Split(new[] { ';' }, StringSplitOptions.RemoveEmptyEntries);

            var dataGridColumns = dataGrid.Columns.OrderBy(x => x.DisplayIndex);

            // Sort the columns in display index order so menu header order matchs display column order
            if (pbRebuild == false)
                // Initially the datagrid column order is such that display indexes are the same as the col indexes
                if (colIndexes.Length > 0)
                    dataGridColumns = dataGrid.Columns.OrderBy(x => Convert.ToInt16(colIndexes[x.DisplayIndex]));

            if (mnuAlpha.IsChecked)
                dataGridColumns = dataGrid.Columns.OrderBy(x => x.Header.ToString());

            AllColumnsHeaders = "";
            foreach (var col in dataGridColumns)
            {
                // All column name to a list of all column headers for later use.
                AllColumnsHeaders = $"{col.Header.ToString().Replace("\n", " ").Replace("\r", " ")};{AllColumnsHeaders}";

                // Add new menu item in display order.
                ContextMenu_AddNewMenuItem(col);
            }

            string sTemp = VisibleColumns;
            VisibleColumns = null;
            VisibleColumns = sTemp;

        }

        private void ContextMenu_AddNewMenuItem(DataGridColumn col)
        {
            var menuItem = new MenuItem { Header = col.Header.ToString().Replace("\n", " ").Replace("\r", " "), StaysOpenOnClick = true };
            var saVisibleColumns = new List<string> { string.Empty };
            if (VisibleColumns != null)
            {
                saVisibleColumns = VisibleColumns.Split(new[] { ';' }, StringSplitOptions.RemoveEmptyEntries).ToList();
            }

            menuItem.IsChecked = (saVisibleColumns.Contains(menuItem.Header));
            menuItem.Click += (sender, e) => { ContextMenu_ColumnName_Click(sender); };

            theContextMenu.Items.Add(menuItem);
        }

        private void ContextMenu_ColumnName_Click(object sender)
        {
            var mi = sender as MenuItem;

            // Get the column name that was clicked
            string colName = mi.Header.ToString();


            // Capture new visible columns list
            Settings_SaveVisibleColumns(mi, colName);
        }

        #endregion "ContextMenu Methods and Events"

        #region "Settings Methods"

        private void Settings_SaveVisibleColumns(MenuItem mi, string colName)
        {
            if (theContextMenu.Items.Count - nBaseItems < dataGrid.Columns.Count)
                return;

            // Put the visible column names into an array
            var saVisibleColumns = VisibleColumns.Split(new char[] { ';' }, StringSplitOptions.RemoveEmptyEntries).ToList();
            if (saVisibleColumns != null && saVisibleColumns.Count > 0 &&
                saVisibleColumns[saVisibleColumns.Count - 1].StartsWith("-"))
                saVisibleColumns.RemoveAt(saVisibleColumns.Count - 1);

            // If the menu item is unchecked (column is not visible)
            if (!mi.IsChecked)
                // Make the column visible by adding its name to the Visible Columns list
                saVisibleColumns.Add(colName);

            else
            // Hide the column by removing its name from the VisibleColumns list
            if (saVisibleColumns.Contains(colName) && saVisibleColumns.Count > 1)
                saVisibleColumns.Remove(colName);

            VisibleColumns = string.Join(";", saVisibleColumns) + ";";
        }

        private void Settings_SaveDisplayIndexes(object sender)
        {
            // Capture the new column order
            AllColumnDisplayIndexes = "";
            foreach (DataGridColumn col in ((DataGrid)sender).Columns)
            {
                AllColumnDisplayIndexes +=
                    (AllColumnDisplayIndexes.Length > 0 ? ";" : "") + col.DisplayIndex;
            }

            DisplayIndexes = AllColumnDisplayIndexes;
        }

        #endregion "Settings Methods"

        #region DisplayIndexes (DependencyProperty)

        public string DisplayIndexes
        {
            get { return (string)GetValue(DisplayIndexesProperty); }
            set { SetValue(DisplayIndexesProperty, value); }
        }

        public static readonly DependencyProperty DisplayIndexesProperty =
            DependencyProperty.Register("DisplayIndexes", typeof(string), typeof(WpfDataGridConfigurationBehavior), new PropertyMetadata("", OnDisplayIndexesChanged));

        private static void OnDisplayIndexesChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            ((WpfDataGridConfigurationBehavior)d).DisplayIndexesChanged(e);
        }

        public void DisplayIndexesChanged(DependencyPropertyChangedEventArgs e)
        {
            // Persist the new column order
            if (dataGrid != null && !DontPersistColumnsOrder)
                Settings_Save(DataGridName + "DisplayIndexes", AllColumnDisplayIndexes);
        }

        #endregion "DisplayIndexes (DependencyProperty)"

        #region VisibleColumns (DependencyProperty)

        /// <summary>
        /// 
        /// Gets or sets a value indicating the names of columns 
        /// (as they appear in the column header) to be visible, seperated by a semicolon.
        /// 
        /// Columns whose names are not here will be hidden.
        /// </summary>

        public string VisibleColumns
        {
            get { return (string)GetValue(VisibleColumnsProperty); }
            set { SetValue(VisibleColumnsProperty, value); }
        }

        private void VisibleColumns_Initialize()
        {
            // Get saved VisibleColumns from app.config
            // Initialize VisibleColumns
            VisibleColumns = string.IsNullOrEmpty(VisibleColumns.Replace("\n", " ").Replace("\r", " ")) ? AllColumnsHeaders : VisibleColumns;
        }


        public static readonly DependencyProperty VisibleColumnsProperty =
            DependencyProperty.Register("VisibleColumns", typeof(string), typeof(WpfDataGridConfigurationBehavior), new PropertyMetadata("", OnVisibleColumnsChanged));

        private static void OnVisibleColumnsChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            ((WpfDataGridConfigurationBehavior)d).VisibleColumnsChanged(e);
        }



        /// <summary>
        /// 
        /// Updates the display
        /// 
        /// </summary>
        /// <param name="e"></param>

        public void VisibleColumnsChanged(DependencyPropertyChangedEventArgs e)
        {
            if (theContextMenu == null)
                return;

            if (e.NewValue != null)
            {
                var showTheseColumns = e.NewValue.ToString().Split(new[] { ';' }, StringSplitOptions.RemoveEmptyEntries);
                var saContextMenuVisibleItems = new List<string>();

                int iCol = 0;

                foreach (MenuItem menuItem in theContextMenu.Items)
                {
                    // Show/Hide the Context Menu item's checkmark.
                    if (menuItem.FontWeight == FontWeights.Bold) continue;

                    menuItem.IsChecked = showTheseColumns.Contains(menuItem.Header.ToString());
                    if (menuItem.IsChecked) saContextMenuVisibleItems.Add(menuItem.Header.ToString());

                    mnuShowAll.IsChecked = mnuShowAll.IsChecked && menuItem.IsChecked;

                    // Assign menu item's column's DisplayIndex in display order, (i.e. in menu item order), looking up each column by header name.)
                    if (mnuAlpha.IsChecked == false)
                        dataGrid.Columns.First(x => x.Header.ToString().Replace("\n", " ").Replace("\r", " ") == menuItem.Header.ToString()).DisplayIndex = iCol++;
                }

                // Show the columns
                foreach (var col in dataGrid.Columns)
                    col.Visibility =
                        showTheseColumns.Contains(col.Header.ToString().Replace("\n", " ").Replace("\r", " "))
                        && (saContextMenuVisibleItems.Contains(col.Header.ToString().Replace("\n", " ")
                            .Replace("\r", " ")))
                            ? Visibility.Visible
                            : Visibility.Collapsed;

                // Persist the new visible columns list

                if (dataGrid != null && !DontPersistVisibleColumns)
                    Settings_Save(DataGridName + "VisibleColumns", VisibleColumns);

            }
        }

        #endregion "VisibleColumns"

        public static void Settings_Save(string propertyName, string propertyValue)
        {
            foreach (SettingsPropertyValue property in Settings.Default.PropertyValues)
            {
                if (propertyName == property.Name)
                {
                    property.PropertyValue = propertyValue;
                    Settings.Default.Save();
                }
            }
        }

    }
    
     public static class WpfDataGridConfigurationBehaviorFinder
    {
        public static T FindChild<T>(DependencyObject depObj) where T : DependencyObject
        {
            // Confirm obj is valid. 
            if (depObj == null) return null;

            // success case
            if (depObj is T) return depObj as T;

            for (int i = 0; i < VisualTreeHelper.GetChildrenCount(depObj); i++)
            {
                T obj = FindChild<T>(VisualTreeHelper.GetChild(depObj, i));
                if (obj != null) return obj;
            }
            return null;
        }

        public interface IBreakVisualParenting
        {
            DependencyObject Parent { get; }
        }

        public static T LastVisualAncestorOfType<T>(this DependencyObject element) where T : DependencyObject
        {
            T item = null;

            var parent = VisualTreeHelper.GetParent(element);
            while (parent != null)
            {
                if (parent is T)
                    item = (T)parent;
                if (parent is IBreakVisualParenting)
                {
                    parent = ((IBreakVisualParenting)parent).Parent;
                }
                else
                    parent = VisualTreeHelper.GetParent(parent);
            }

            return item;
        }

    }
}