Referencing objects in XAML design data - wpf

Question

How can I reference the same object twice (or more often) in a XAML design data file?
I tried to use {x:Reference}, but this does not seem to work.
Here is an example:
The combo box in the cells of the second column of the sample's data grid displays a list of "data types". The list of available data types comes from the Types property of the main window's view model (= the data context). The list of items in the grid comes from the Items property of the view model. Each item has a Name and a Type column, where Type references a data type object.
The sample grid looks like this:
Here is the XAML design data which should show the same grid contents in the Visual Studio designer (but it doesn't):
<?xml version="1.0" encoding="utf-8" ?>
<local:MainWindowViewModel
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:DataGridSample"
>
<local:MainWindowViewModel.Types>
<local:DataType Name="String" x:Name="String"/>
<local:DataType Name="Integer" x:Name="Integer"/>
</local:MainWindowViewModel.Types>
<local:MainWindowViewModel.Items>
<local:Item Name="Lorem" Type="{x:Reference String}"/>
<local:Item Name="Ipsum" Type="{x:Reference Integer}"/>
</local:MainWindowViewModel.Items>
</local:MainWindowViewModel>
Above, I am using {x:Reference String} to obtain a reference to the object that was created by <local:DataType Name="String" x:Name="String"/>.
In the Visual Studio designer, the list is empty, and the error message "Errors found in markup: ... DesignData.xaml" is displayed. In the editor for the design data XAML files, I get the error message "Service provider is missing the INameResolver service".
Is there any alternative to {x:Reference} which I could use in design data files to refer to an object?
For completeness, here are the remaining files of my sample:
MainWindow.xaml:
<Window x:Class="DataGridSample.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
mc:Ignorable="d"
Title="Sample" Height="300" Width="400"
d:DataContext="{d:DesignData Source=DesignData.xaml}">
<Window.Resources>
<CollectionViewSource x:Key="types" Source="{Binding Types}"/>
</Window.Resources>
<Grid>
<DataGrid ItemsSource="{Binding Items}" AutoGenerateColumns="False">
<DataGrid.Columns>
<DataGridTextColumn Binding="{Binding Name}" Header="Name" Width="*"/>
<DataGridComboBoxColumn SelectedItemBinding="{Binding Type}"
ItemsSource="{Binding Source={StaticResource types}}"
DisplayMemberPath="Name"
Header="Type" Width="*"/>
</DataGrid.Columns>
</DataGrid>
</Grid>
</Window>
MainWindow.xaml.cs:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
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 DataGridSample
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
readonly MainWindowViewModel _viewModel = new MainWindowViewModel();
public MainWindow()
{
InitializeComponent();
DataContext = _viewModel;
}
}
}
MainWindowViewModel.cs:
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Text;
namespace DataGridSample
{
public class MainWindowViewModel
{
private readonly ObservableCollection<DataType> _dataTypes;
private readonly ObservableCollection<Item> _items;
public MainWindowViewModel()
{
DataType typeString = new DataType {Name = "String"};
DataType typeInteger = new DataType {Name = "Integer"};
_dataTypes = new ObservableCollection<DataType> {typeString, typeInteger};
_items = new ObservableCollection<Item>
{
new Item {Name = "Lorem", Type = typeString},
new Item {Name = "Ipsum", Type = typeInteger}
};
}
public ObservableCollection<DataType> Types
{
get
{
return _dataTypes;
}
}
public ObservableCollection<Item> Items
{
get
{
return _items;
}
}
}
public class DataType
{
public string Name { get; set; }
}
public class Item
{
public string Name { get; set; }
public DataType Type { get; set; }
}
}

Answer 1

Background on why x:Reference doesn't work .....
x:Reference is a XAML 2009 feature.
You can't use x:Reference in XAML markup that is compiled according to the MSDN docs.
http://msdn.microsoft.com/en-us/library/ee795380.aspx
It's designed for loose XAML...e.g. if you create a XAML Page (.xaml) and load it via Internet Explorer.
When you use DesignData the Designer effectively creates and compiles a new class whose shape and content is as described in your DesignData file.
There's no support for it in Visual Studio/Blend Designers.
http://www.infoq.com/news/2009/12/XAML-2009-Future
Here's a counter argument.
Here is the explanation from Adam Nathan's WPF 4 unleashed book: "The
x:Reference markup extension is often mistakenly associated with the
XAML2009 features that can only be used from loose XAML at the time
of this writing. Although x:Reference is a new feature in WPF 4, it
can be used from XAML2006 just fine as long as your project is
targeting version 4 or later of the .NET Framework. One glitch is
that the XAML designer in Visual Studio 2010 doesn�t properly handle
x:Reference, so it gives the following design-time error that you can
safely ignore: Service provider is missing the INameResolver service"
http://wpftutorial.net/XAML2009.html
Workaround solution ...