WPF DataGrid: Binding DataGridColumn visibility to ContextMenu MenuItems IsChecked (MVVM)

Question

I want to control DataGrid column visibility through a ContextMenu available to the user by right-clicking the column header. The ContextMenu displays the names of all available columns. I am using MVVM design pattern.

My question is: How do I bind the DataGridColumn's Visibility property to the IsChecked property of a MenuItem located in the ContextMenu.

Some mockup code:

<UserControl.Resources>         
    <ContextMenu x:Key="ColumnHeaderContextMenu">  
        <MenuItem Header="Menu Item..1" IsCheckable="True" />  
    </ContextMenu>  
    <Style x:Key="ColumnHeaderStyle" 
           TargetType="{x:Type toolkit:DataGridColumnHeader}">  
        <Setter Property="ContextMenu" 
                Value="{StaticResource ColumnHeaderContextMenu}" />  
    </Style>  
    <BooleanToVisibilityConverter x:Key="booleanToVisibilityConverter" />  
</UserControl.Resources>  

...flaf flaf flaf

<toolkit:DataGrid x:Name="MyGrid" AutoGenerateColumns="False" 
    ItemsSource="{Binding MyCollection, Mode=Default}" 
    EnableColumnVirtualization="True" IsReadOnly="True" 
    ColumnHeaderStyle="{StaticResource ColumnHeaderStyle}">  
    <toolkit:DataGrid.Columns>  
        <toolkit:DataGridTextColumn Binding="{Binding Path=MyEntry}" 
            Header="MyEntry" Visibility="{Binding IsChecked, Converter=
                {StaticResource booleanToVisibilityConverter}.... />
    </toolkit:DataGrid.Columns>     
</toolkit:DataGrid>  

If I am being unclear please let me know and I will attempt to elaborate.

Cheers,

Carpospore

Answer 1

Updated 2021-09-29: Pasted the code from my old blog. I haven't worked with WPF in many years I know nothing about it anymore. This site has limits on post length so I had to share some of the example code using CodePile. See the links at bottom for usage. I believe the idea was the sample I made works in many scenarios versus just auto generated columns. I was working on a project where the columns were not known until runtime and could change dynamically. Also note there was a png file for the "eye" graphic, you'll need your own probably.

DataGridAPs.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Markup;
using System.Windows.Media;
using Microsoft.Windows.Controls;
using Microsoft.Windows.Controls.Primitives;

namespace CanUserHideColumnDemo
{
    public static class DataGridAPs
    {
        #region HideColumns
        #region HideColumnsHeader
        public static readonly DependencyProperty HideColumnsHeaderProperty =
            DependencyProperty.RegisterAttached("HideColumnsHeader",
            typeof(object), typeof(DataGridAPs));

        public static object GetHideColumnsHeader(DataGrid obj)
        {
            return obj.GetValue(HideColumnsHeaderProperty);
        }

        public static void SetHideColumnsHeader(DataGrid obj, object value)
        {
            obj.SetValue(HideColumnsHeaderProperty, value);
        }
        #endregion HideColumnsHeader

        #region HideColumnsHeaderTemplate
        public static readonly DependencyProperty HideColumnsHeaderTemplateProperty =
            DependencyProperty.RegisterAttached("HideColumnsHeaderTemplate",
            typeof(DataTemplate), typeof(DataGridAPs));

        public static DataTemplate GetHideColumnsHeaderTemplate(DataGrid obj)
        {
            return (DataTemplate)obj.GetValue(HideColumnsHeaderTemplateProperty);
        }

        public static void SetHideColumnsHeaderTemplate(DataGrid obj, DataTemplate value)
        {
            obj.SetValue(HideColumnsHeaderTemplateProperty, value);
        }
        #endregion HideColumnsHeaderTemplate

        #region HideColumnsIcon
        public static readonly DependencyProperty HideColumnsIconProperty =
            DependencyProperty.RegisterAttached("HideColumnsIcon",
            typeof(object), typeof(DataGridAPs));

        public static object GetHideColumnsIcon(DataGrid obj)
        {
            return obj.GetValue(HideColumnsIconProperty);
        }

        public static void SetHideColumnsIcon(DataGrid obj, object value)
        {
            obj.SetValue(HideColumnsIconProperty, value);
        }
        #endregion HideColumnsIcon

        #region CanUserHideColumns
        public static readonly DependencyProperty CanUserHideColumnsProperty =
            DependencyProperty.RegisterAttached("CanUserHideColumns",
            typeof(bool), typeof(DataGridAPs),
            new UIPropertyMetadata(false, OnCanUserHideColumnsChanged));

        public static bool GetCanUserHideColumns(DataGrid obj)
        {
            return (bool)obj.GetValue(CanUserHideColumnsProperty);
        }

        public static void SetCanUserHideColumns(DataGrid obj, bool value)
        {
            obj.SetValue(CanUserHideColumnsProperty, value);
        }

        private static void OnCanUserHideColumnsChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            DataGrid dataGrid = d as DataGrid;
            if (dataGrid == null)
                return;

            if ((bool)e.NewValue == false)
            {
                dataGrid.Loaded -= new RoutedEventHandler(dataGrid_Loaded);
                RemoveAllItems(dataGrid);
                return;
            }

            if (!dataGrid.IsLoaded)
            {
                dataGrid.Loaded -= new RoutedEventHandler(dataGrid_Loaded);
                dataGrid.Loaded += new RoutedEventHandler(dataGrid_Loaded);
            }
            else
                SetupColumnHeaders(dataGrid);
        }

        private static void dataGrid_Loaded(object sender, RoutedEventArgs e)
        {
            DataGrid dataGrid = sender as DataGrid;
            if (dataGrid == null)
                return;

            if (BindingOperations.IsDataBound(dataGrid, DataGrid.ItemsSourceProperty))
            {
                Binding b = BindingOperations.GetBinding(dataGrid, DataGrid.ItemsSourceProperty);
                dataGrid.TargetUpdated += new EventHandler<DataTransferEventArgs>(dataGrid_TargetUpdated);

                string xaml = XamlWriter.Save(b);
                Binding b2 = XamlReader.Parse(xaml) as Binding;
                if (b2 != null)
                {
                    b2.NotifyOnTargetUpdated = true;
                    BindingOperations.ClearBinding(dataGrid, DataGrid.ItemsSourceProperty);
                    BindingOperations.SetBinding(dataGrid, DataGrid.ItemsSourceProperty, b2);
                }
            }
            else
                SetupColumnHeaders(dataGrid);
        }

        private static void dataGrid_TargetUpdated(object sender, DataTransferEventArgs e)
        {
            if (e.Property != DataGrid.ItemsSourceProperty)
                return;

            DataGrid dataGrid = sender as DataGrid;
            if (dataGrid == null)
                return;

            EventHandler handler = null;
            handler = delegate
            {
                RemoveAllItems(dataGrid);
                if (SetupColumnHeaders(dataGrid))
                    dataGrid.LayoutUpdated -= handler;
            };

            dataGrid.LayoutUpdated += handler;
        }

        private static DataGridColumnHeader[] GetColumnHeaders(DataGrid dataGrid)
        {
            if (dataGrid == null)
                return null;

            dataGrid.UpdateLayout();
            DataGridColumnHeader[] columnHeaders = CustomVisualTreeHelper<DataGridColumnHeader>.FindChildrenRecursive(dataGrid);


            return (from DataGridColumnHeader columnHeader in columnHeaders
                    where columnHeader != null && columnHeader.Column != null
                    select columnHeader).ToArray();
        }

        private static string GetColumnName(DataGridColumn column)
        {
            if (column == null)
                return string.Empty;

            if (column.Header != null)
                return column.Header.ToString();
            else
                return string.Format("Column {0}", column.DisplayIndex);
        }

        private static MenuItem GenerateItem(DataGrid dataGrid, DataGridColumn column)
        {
            if (column == null)
                return null;

            MenuItem item = new MenuItem();
            item.Tag = column;

            item.Header = GetColumnName(column);
            if (string.IsNullOrEmpty(item.Header as string))
                return null;

            item.ToolTip = string.Format("Toggle column '{0}' visibility.", item.Header);

            item.IsCheckable = true;
            item.IsChecked = column.Visibility == Visibility.Visible;

            item.Checked += delegate
            {
                SetItemIsChecked(dataGrid, column, true);
            };

            item.Unchecked += delegate
            {
                SetItemIsChecked(dataGrid, column, false);
            };

            return item;
        }

        public static MenuItem[] GetAttachedItems(DataGridColumnHeader columnHeader)
        {
            if (columnHeader == null || columnHeader.ContextMenu == null)
                return null;

            ItemsControl itemsContainer = (from object i in columnHeader.ContextMenu.Items
                                           where i is MenuItem && ((MenuItem)i).Tag != null && ((MenuItem)i).Tag.ToString() == "ItemsContainer"
                                           select i).FirstOrDefault() as MenuItem;

            if (itemsContainer == null)
                itemsContainer = columnHeader.ContextMenu;

            return (from object i in itemsContainer.Items
                    where i is MenuItem && ((MenuItem)i).Tag is DataGridColumn
                    select i).Cast<MenuItem>().ToArray();
        }

        private static DataGridColumn GetColumnFromName(DataGrid dataGrid, string columnName)
        {
            if (string.IsNullOrEmpty(columnName))
                return null;

            foreach (DataGridColumn column in dataGrid.Columns)
            {
                if (GetColumnName(column) == columnName)
                    return column;
            }

            return null;
        }

        private static DataGridColumnHeader GetColumnHeaderFromColumn(DataGrid dataGrid, DataGridColumn column)
        {
            if (dataGrid == null || column == null)
                return null;

            DataGridColumnHeader[] columnHeaders = GetColumnHeaders(dataGrid);
            return (from DataGridColumnHeader columnHeader in columnHeaders
                    where columnHeader.Column == column
                    select columnHeader).FirstOrDefault();
        }

        public static void RemoveAllItems(DataGrid dataGrid)
        {
            if (dataGrid == null)
                return;

            foreach (DataGridColumn column in dataGrid.Columns)
            {
                RemoveAllItems(dataGrid, column);
            }
        }

        public static void RemoveAllItems(DataGrid dataGrid, DataGridColumn column)
        {
            if (dataGrid == null || column == null)
                return;

            DataGridColumnHeader columnHeader = GetColumnHeaderFromColumn(dataGrid, column);
            List<MenuItem> itemsToRemove = new List<MenuItem>();

            if (columnHeader == null)
                return;

            // Mark items and/or items container for removal.
            if (columnHeader.ContextMenu != null)
            {
                foreach (object item in columnHeader.ContextMenu.Items)
                {
                    if (item is MenuItem && ((MenuItem)item).Tag != null
                        && (((MenuItem)item).Tag.ToString() == "ItemsContainer" || ((MenuItem)item).Tag is DataGridColumn))
                        itemsToRemove.Add((MenuItem)item);
                }
            }

            // Remove items and/or items container.
            foreach (MenuItem item in itemsToRemove)
            {
                columnHeader.ContextMenu.Items.Remove(item);
            }
        }

        public static void ResetupColumnHeaders(DataGrid dataGrid)
        {
            RemoveAllItems(dataGrid);
            SetupColumnHeaders(dataGrid);
        }

        private static void SetItemIsChecked(DataGrid dataGrid, DataGridColumn column, bool isChecked)
        {
            if (dataGrid == null || column == null)
                return;

            // Deny request if there are no other columns visible. Otherwise,
            // they'd have no way of changing the visibility of any columns
            // again.
            //if (!isChecked && (from DataGridColumn c in dataGrid.Columns
            //                   where c.Visibility == Visibility.Visible
            //                   select c).Count() < 2)
            //    return;

            if (isChecked && column.Visibility != Visibility.Visible)
            {
                ShowColumn(dataGrid, column);
            }
            else if (!isChecked)
                column.Visibility = Visibility.Hidden;

            DataGridColumnHeader[] columnHeaders = GetColumnHeaders(dataGrid);
            ItemsControl itemsContainer = null;
            object containerHeader = GetHideColumnsHeader(dataGrid);

            foreach (DataGridColumnHeader columnHeader in columnHeaders)
            {
                itemsContainer = null;
                if (columnHeader != null)
                {
                    if (columnHeader.ContextMenu == null)
                        continue;

                    itemsContainer = (from object i in columnHeader.ContextMenu.Items
                                      where i is MenuItem && ((MenuItem)i).Header == containerHeader
                                      select i).FirstOrDefault() as MenuItem;
                }

                if (itemsContainer == null)
                    itemsContainer = columnHeader.ContextMenu;

                foreach (object item in itemsContainer.Items)
                {
                    if (item is MenuItem && ((MenuItem)item).Tag != null && ((MenuItem)item).Tag is DataGridColumn
                        && ((MenuItem)item).Header.ToString() == GetColumnName(column))
                    {
                        ((MenuItem)item).IsChecked = isChecked;
                    }
                }
            }
        }

        private static void SetupColumnHeader(DataGridColumnHeader columnHeader)
        {
            if (columnHeader == null)
                return;

            DataGrid dataGrid = CustomVisualTreeHelper<DataGrid>.FindAncestor(columnHeader);
            if (dataGrid == null)
                return;

            DataGridColumnHeader[] columnHeaders = GetColumnHeaders(dataGrid);
            if (columnHeaders == null)
                return;

            SetupColumnHeader(dataGrid, columnHeaders, columnHeader);
        }

        private static void SetupColumnHeader(DataGrid dataGrid, DataGridColumnHeader[] columnHeaders, DataGridColumnHeader columnHeader)
        {
            if (columnHeader.ContextMenu == null)
                columnHeader.ContextMenu = new ContextMenu();

            ItemsControl itemsContainer = null;
            itemsContainer = columnHeader.ContextMenu;

            object containerHeader = GetHideColumnsHeader(dataGrid);
            if (containerHeader != null)
            {
                MenuItem ic = (from object i in columnHeader.ContextMenu.Items
                               where i is MenuItem && ((MenuItem)i).Tag != null && ((MenuItem)i).Tag.ToString() == "ItemsContainer"
                               select i).FirstOrDefault() as MenuItem;

                if (ic == null)
                {
                    itemsContainer = new MenuItem()
                    {
                        Header = containerHeader,
                        HeaderTemplate = GetHideColumnsHeaderTemplate(dataGrid) as DataTemplate,
                        Icon = GetHideColumnsIcon(dataGrid),
                        Tag = "ItemsContainer"
                    };
                    columnHeader.ContextMenu.Items.Add(itemsContainer);
                }
                else
                    return;
            }

            foreach (DataGridColumnHeader columnHeader2 in columnHeaders)
            {
                if (columnHeader2 != columnHeader
                    && itemsContainer is ContextMenu
                    && columnHeader2.ContextMenu == itemsContainer)
                {
                    continue;
                }
                itemsContainer.Items.Add(GenerateItem(dataGrid, columnHeader2.Column));
            }
        }

        public static bool SetupColumnHeaders(DataGrid dataGrid)
        {
            DataGridColumnHeader[] columnHeaders = GetColumnHeaders(dataGrid);
            if (columnHeaders == null || columnHeaders.Count() == 0)
                return false;

            RemoveAllItems(dataGrid);
            columnHeaders = GetColumnHeaders(dataGrid);
            foreach (DataGridColumnHeader columnHeader in columnHeaders)
            {
                SetupColumnHeader(dataGrid, columnHeaders, columnHeader);
            }

            return true;
        }

        /// <summary>
        /// Shows a column within the datagrid, which is not straightforward
        /// because the datagrid not only hides a column when you tell it to
        /// do so, but it also completely destroys its associated column
        /// header. Meaning we need to set it up again. Before we can do
        /// so we have to turn all columns back on again so we can get a
        /// complete list of their column headers, then turn them back off
        /// again.
        /// </summary>
        /// <param name="dataGrid"></param>
        /// <param name="column"></param>
        private static void ShowColumn(DataGrid dataGrid, DataGridColumn column)
        {
            if (dataGrid == null || column == null)
                return;

            column.Visibility = Visibility.Visible;

            // Turn all columns on, but store their original visibility so we
            // can restore it after we're done.
            Dictionary<DataGridColumn, Visibility> vis = new Dictionary<DataGridColumn, Visibility>();
            foreach (DataGridColumn c in dataGrid.Columns)
            {
                vis.Add(c, c.Visibility);
                c.Visibility = Visibility.Visible;
            }
            dataGrid.UpdateLayout();

            DataGridColumnHeader columnHeader = GetColumnHeaderFromColumn(dataGrid, column);
            SetupColumnHeader(columnHeader);

            foreach (DataGridColumn c in vis.Keys)
            {
                if ((Visibility)vis[c] != Visibility.Visible)
                {
                    c.Visibility = (Visibility)vis[c];
                }
            }
            dataGrid.UpdateLayout();

            // Now we need to uncheck items that are associated with hidden
            // columns.
            SyncItemsOnColumnHeader(columnHeader);
        }

        private static void SyncItemsOnColumnHeader(DataGridColumnHeader columnHeader)
        {
            bool isVisible;
            foreach (MenuItem item in GetAttachedItems(columnHeader))
            {
                if (item.Tag is DataGridColumn)
                {
                    isVisible = ((DataGridColumn)item.Tag).Visibility == Visibility.Visible ? true : false;
                    if (item.IsChecked != isVisible)
                    {
                        item.IsChecked = isVisible;
                    }
                }
            }
        }
        #endregion CanUserHideColumns

        #region CustomVisualTreeHelper
        private static class CustomVisualTreeHelper<TReturn> where TReturn : DependencyObject
        {
            public static TReturn FindAncestor(DependencyObject descendant)
            {
                DependencyObject parent = descendant;
                while (parent != null && !(parent is TReturn))
                {
                    parent = VisualTreeHelper.GetParent(parent);
                }

                if (parent != null)
                {
                    return (TReturn)parent;
                }
                return default(TReturn);
            }

            public static TReturn FindChild(DependencyObject parent)
            {
                int childCount = VisualTreeHelper.GetChildrenCount(parent);
                DependencyObject child = null;

                for (int childIndex = 0; childIndex < childCount; childIndex++)
                {
                    child = VisualTreeHelper.GetChild(parent, childIndex);
                    if (child is TReturn)
                    {
                        return (TReturn)(object)child;
                    }
                }
                return default(TReturn);
            }

            public static TReturn FindChildRecursive(DependencyObject parent)
            {
                int childCount = VisualTreeHelper.GetChildrenCount(parent);
                DependencyObject child = null;

                for (int childIndex = 0; childIndex < childCount; childIndex++)
                {
                    child = VisualTreeHelper.GetChild(parent, childIndex);
                    if (child is TReturn)
                    {
                        return (TReturn)(object)child;
                    }
                    else
                    {
                        child = CustomVisualTreeHelper<TReturn>.FindChildRecursive(child);
                        if (child is TReturn)
                        {
                            return (TReturn)(object)child;
                        }
                    }
                }
                return default(TReturn);
            }

            public static TReturn[] FindChildren(DependencyObject parent)
            {
                int childCount = VisualTreeHelper.GetChildrenCount(parent);
                DependencyObject child = null;
                List<TReturn> children = new List<TReturn>(childCount);

                for (int childIndex = 0; childIndex < childCount; childIndex++)
                {
                    child = VisualTreeHelper.GetChild(parent, childIndex);
                    if (child is TReturn)
                    {
                        children[childIndex] = (TReturn)(object)child;
                    }
                }
                return children.ToArray();
            }

            public static TReturn[] FindChildrenRecursive(DependencyObject parent)
            {
                int childCount = VisualTreeHelper.GetChildrenCount(parent);
                DependencyObject child = null;
                List<TReturn> children = new List<TReturn>();

                for (int childIndex = 0; childIndex < childCount; childIndex++)
                {
                    child = VisualTreeHelper.GetChild(parent, childIndex);
                    if (child is TReturn)
                    {
                        children.Add((TReturn)(object)child);
                    }

                    children.AddRange(CustomVisualTreeHelper<TReturn>.FindChildrenRecursive(child));
                }
                return children.ToArray();
            }
        }
        #endregion CustomVisualTreeHelper
        #endregion HideColumns
    }
}

Window1.xaml Window1.xaml.cs

Infringe

Just looked through it and it looks solid. I would give you a vote up but lack 1 in reputation :) – Carpospore

This worked beautifully!! Awesome stuff. Now I need to study it in detail once my deadline is over :) – Wavell

SO rules suggest that linking to a blog rather than posting the explicit content is not ideal. Can you actually answer the Q here? – Indices

And the blog is dead.... Would be nice to see the solution. – Tomlinson

Pasted relevant code in answer, good luck. – Infringe

Answer 2

I've been looking for a generic, XAML (i.e., no code-behind), automatic and simple example of a column chooser context menu that binds to a WPF DataGrid column header. I've read literally hundreds of articles, but none of them seem to do exactly the right thing, or they're no generic enough. So here's what I think is the best combined solution:

First, put these in the resource dictionary. I'll leave it as an exercise to the reader to write the Visibility/Boolean converter to ensure the checkboxes check when the column is visible and vice-versa. Note that by defining x:Shared="False" for the context menu resource, it'll get instance-specific state which means that you can use this single template/resource for all your datagrids and they'll all maintain their own state.

<Converters:VisiblityToInverseBooleanConverter x:Key="VisiblityToInverseBooleanConverter"/>

<ContextMenu x:Key="ColumnChooserMenu" x:Shared="False"
             DataContext="{Binding Path=PlacementTarget, RelativeSource={RelativeSource Self}}" 
             ItemsSource="{Binding Columns, RelativeSource={RelativeSource AncestorType={x:Type sdk:DataGrid}}}">
    <ContextMenu.ItemContainerStyle>
        <Style TargetType="MenuItem">
            <Setter Property="Header" Value="{Binding Header}"/>
            <Setter Property="AutomationProperties.Name" Value="{Binding Header}"/>
            <Setter Property="IsCheckable" Value="True" />
            <Setter Property="IsChecked" Value="{Binding Visibility, Mode=TwoWay, Converter={StaticResource VisiblityToInverseBooleanConverter}}" />
        </Style>
    </ContextMenu.ItemContainerStyle>
</ContextMenu>

<Style x:Key="ColumnHeaderStyle" TargetType="{x:Type Primitives:DataGridColumnHeader}">
    <Setter Property="ContextMenu" Value="{StaticResource ColumnChooserMenu}" />
</Style>

<ContextMenu x:Key="GridItemsContextMenu" >
    <MenuItem Header="Launch Do Some other action"/>
</ContextMenu>

Then define the DataGrid as follows (where OrdersQuery is some data source exposed by the View-model):

<sdk:DataGrid ItemsSource="{Binding OrdersQuery}"
              AutoGenerateColumns="True" 
              ColumnHeaderStyle="{StaticResource ColumnHeaderStyle}"
              ContextMenu="{StaticResource GridItemsContextMenu}">

  <!-- rest of datagrid stuff goes here -->

</sdk:DataGrid>

This will give you the following:

1. A context menu bound to the column headings which acts as a column chooser.
2. A context menu bound to the items in the grid (to perform actions on the items themselves - again, the binding of the actions is an exercise for the reader).

Hope this helps people who've been looking for an example like this.

Indices

This answer should be higher. Simple, elegant solution. – Biggin

Very neat solution! However one note: it only works if columns are auto generated. Obviously of course, but I it's worth mentioning. – Devland

Are you sure? Pretty certain it works for auto-generated or explicitly-generated columns (but haven't tried it for a couple of years so could be wrong). – Indices

It works for me and I am specifying my columns manually in XAML – Beslobber

Worked like a charm :). Thanks for sharing. This is way better than accepted answer. – Forrester

A good solution. However, the Header property of each column must be set to a simple string in order for it to work properly. There may be times, particularly in more complex grids, where this is not the case. An alternative might be to use the HeaderStringFormat property to store the text to use for the context menu item, and bind to that property instead. – Jasper

Answer 3

I know this is a bit old. But I was looking at doing this and this post is much simpler: http://iimaginec.wordpress.com/2011/07/25/binding-wpf-toolkit%E2%80%99s-datagridcolumn-to-a-viewmodel-datacontext-propogation-for-datagrid-columns-the-mvvm-way-to-interact-with-datagridcolumn/

All you need to do is set DataContext on the Columns and then bind Visibility to your ViewModel as per normal! :) Simple and effective

Harmonicon

Works great for me in 3.5 + WPF Toolkit – Kleiman

+1 That is the best explanation of the pattern that I've seen, thanks. – Disunite

Answer 4

Ok, this has been quite the exercise for a WPF n00b.

IanR thanks for the suggestion I used a similar aproach but it dosent take you all the way.

Here is what I have come up with if anyone can find a more consistent way of doing it I will appreciate any comments:

Impediments:

1. DataGridColumnHeader does not support a context menu. Therefore the context menu needs to be applied as a Style.

2. The contextmenu has its own datacontext so we have to use findancestor to link it to the ViewModels datacontext.

3. ATM the DataGrid control does not parse its datacontext to its Columns. This could be solved in codebehind however we are using the MVVM pattern so I decided to follow jamiers approach

Solution:

Place the following two blocks of code in Window.Resources

    <Style x:Key="ColumnHeaderStyle"
           TargetType="{x:Type toolkit:DataGridColumnHeader}">
        <Setter Property="ContextMenu" 
                Value="{StaticResource ColumnHeaderContextMenu}" />
    </Style>  

    <ContextMenu x:Key="ColumnHeaderContextMenu">
        <MenuItem x:Name="MyMenuItem"
                  IsCheckable="True"
                  IsChecked="{Binding DataContext.IsHidden, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type toolkit:DataGrid}}}"/>
    </ContextMenu>

The datagrid then looks something like this in XAML

        <toolkit:DataGrid x:Name="MyGrid"
                          AutoGenerateColumns="False"
                          ItemsSource="{Binding SampleCollection, Mode=Default}"
                          EnableColumnVirtualization="True"
                          IsReadOnly="True"
                          ColumnHeaderStyle="{StaticResource ColumnHeaderStyle}">
            <toolkit:DataGrid.Columns>
                <toolkit:DataGridTextColumn Binding="{Binding Path=SamplingUser}"
                                            Header="{Binding (FrameworkElement.DataContext).IsHidden, RelativeSource={x:Static RelativeSource.Self}}"
                                            Visibility="{Binding (FrameworkElement.DataContext).IsHidden,
                                                RelativeSource={x:Static RelativeSource.Self},
                                                Converter={StaticResource booleanToVisibilityConverter}}"/>

So the visibility property on the DataGridColumn and the ischeked property are both databound to the IsHidden property on the viewModel.

In the ViewModel:

    public bool IsHidden
    {
        get { return isHidden; }
        set 
        { if (value != isHidden)
            {
                isHidden = value;
                OnPropertyChanged("IsHidden");
                OnPropertyChanged("IsVisible");
            }
        }
    }  

The Helper class defined by Jaimer:

class DataGridSupport
{
    static DataGridSupport() 
    {

        DependencyProperty dp = FrameworkElement.DataContextProperty.AddOwner(typeof(DataGridColumn)); 
        FrameworkElement.DataContextProperty.OverrideMetadata ( typeof(DataGrid), new FrameworkPropertyMetadata(null, FrameworkPropertyMetadataOptions.Inherits, new PropertyChangedCallback(OnDataContextChanged)));

    }

    public static void OnDataContextChanged ( DependencyObject d, DependencyPropertyChangedEventArgs e)
    { 
        DataGrid grid = d as DataGrid ; 
        if ( grid != null  ) 
        {                 
            foreach ( DataGridColumn col in grid.Columns ) 
            { 
                col.SetValue ( FrameworkElement.DataContextProperty,  e.NewValue ); 
            } 
        } 
    }
}

Instanciated in the viewmodel (just to show done through Unity in real project)

    private static DataGridSupport dc = new DataGridSupport();

Cheers,

Carpospore

Answer 5

Instead of booleanToVisibilityConverter you can use x:static

<Setter TargetName="UIElement"  Property="UIElement.Visibility" Value="x:Static Visibility.Hidden" />

Statics in XAML: http://msdn.microsoft.com/en-us/library/ms742135.aspx

Dynode

Voted up only because the previous voter who voted this answer down did not provide any explanation regarding the voting down reason. – Costanzia

Answer 6

I did try to ge this to bind to the ContextMenu using 'ElementName', but in the end, got it work using Properties in the VM, e.g.

bool _isHidden;
public bool IsHidden
{
  get { return _isHidden; }
  set
  {
    if (value != _isHidden)
    {
      _isHidden = value;
      RaisePropertyChanged("IsHidden");
      RaisePropertyChanged("IsVisible");
    }
  }
}

public Visibility IsVisible
{
  get { return IsHidden ? Visibility.Hidden : Visibility.Visible; }
}

and in the XAML:

<Window.ContextMenu>
  <ContextMenu>
    <MenuItem Header="Hidden" IsCheckable="True" IsChecked="{Binding IsHidden}" />
  </ContextMenu>
</Window.ContextMenu>

<toolkit:DataGrid x:Name="MyGrid" AutoGenerateColumns="False" ItemsSource="{Binding MyCollection, Mode=Default}" EnableColumnVirtualization="True" IsReadOnly="True" ColumnHeaderStyle="{StaticResource ColumnHeaderStyle}">
  <toolkit:DataGrid.Columns>
    <toolkit:DataGridTextColumn Binding="{Binding Path=MyEntry}" Header="MyEntry" Visibility="{Binding Path=IsVisible, Mode=OneWay}" />
  </toolkit:DataGrid.Columns>
</toolkit:DataGrid>

Amen

Hi Ian could you elaborate it? I have a datagrid which binds to collection. I want to hide column (visibility) by checking boolean property. E.g Class ContextClass { CollectionForGrid; IsActive; } I am binding CollectionForGrid to Grid & I want to set visiblity of a column base on IsActive property. – Merete

@Rakesh - my best advice would be to open a new question, and I (along with the rest of the SO community) will try and answer it for you :) – Amen