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    <p>Sadly any <code>DataGridColumn</code> hosted under <code>DataGrid.Columns</code> is not part of <code>Visual</code> tree and therefore not connected to the data context of the datagrid. So bindings do not work with their properties such as <code>Visibility</code> or <code>Header</code> etc (although these properties are valid dependency properties!). </p> <p>Now you may wonderhow is that possible? Isn't their <code>Binding</code> property supposed to be bound to the data context? Well it simply is a hack. The binding does not really work. It is actually the datagrid cells that <strong>copy</strong> / <strong>clone</strong> this binding object and use it for displaying their own contents!</p> <p>So now back to solving your issue, I assume that <code>HeaderItems</code> is a property of the object that is set as the <code>DataContext</code> of your parent View. We <em>can</em> connect the <code>DataContext</code> of the view to any <code>DataGridColumn</code> via something we call a <strong><code>ProxyElement</code></strong>.</p> <p>The example below illustrates how to connect a logical child such as <code>ContextMenu</code> or <code>DataGridColumn</code> to the parent View's <code>DataContext</code></p> <pre><code> &lt;Window x:Class="WpfApplicationMultiThreading.Window5" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:vb="http://schemas.microsoft.com/wpf/2008/toolkit" Title="Window5" Height="300" Width="300" &gt; &lt;Grid x:Name="MyGrid"&gt; &lt;Grid.Resources&gt; &lt;FrameworkElement x:Key="ProxyElement" DataContext="{Binding}"/&gt; &lt;/Grid.Resources&gt; &lt;Grid.DataContext&gt; &lt;TextBlock Text="Text Column Header" Tag="Tag Columne Header"/&gt; &lt;/Grid.DataContext&gt; &lt;ContentControl Visibility="Collapsed" Content="{StaticResource ProxyElement}"/&gt; &lt;vb:DataGrid AutoGenerateColumns="False" x:Name="MyDataGrid"&gt; &lt;vb:DataGrid.ItemsSource&gt; &lt;x:Array Type="{x:Type TextBlock}"&gt; &lt;TextBlock Text="1" Tag="1.1"/&gt; &lt;TextBlock Text="2" Tag="1.2"/&gt; &lt;TextBlock Text="3" Tag="2.1"/&gt; &lt;TextBlock Text="4" Tag="2.2"/&gt; &lt;/x:Array&gt; &lt;/vb:DataGrid.ItemsSource&gt; &lt;vb:DataGrid.Columns&gt; &lt;vb:DataGridTextColumn Header="{Binding DataContext.Text, Source={StaticResource ProxyElement}}" Binding="{Binding Text}"/&gt; &lt;vb:DataGridTextColumn Header="{Binding DataContext.Tag, Source={StaticResource ProxyElement}}" Binding="{Binding Tag}"/&gt; &lt;/vb:DataGrid.Columns&gt; &lt;/vb:DataGrid&gt; &lt;/Grid&gt; &lt;/Window&gt; </code></pre> <p>The view above encountered the same binding error that you have found if I did not have implemented the ProxyElement hack. The ProxyElement is any FrameworkElement that <strong>steals</strong> the <code>DataContext</code> from the main View and offers it to the logical child such as <code>ContextMenu</code> or <code>DataGridColumn</code>. For that it must be hosted as a <code>Content</code> into an invisible <code>ContentControl</code> which is under the same View.</p> <p>I hope this guides you in correct direction.</p>
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    1. COI find having to use this hacky proxy stuff really disapointing but I cannot find another way to achieve the same functionality otherwise... Thank you.
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    2. COThis didn't work for me but after reading Josh Smith's article about Virtual Branches I tried adding the OneWayToSource binding on my root control to set the "ProxyElement" DataContext and that worked.
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    3. CO@jpierson, are you using `Silverlight`? Coz it works for me in `WPF`. For silverlight the implementation is different.
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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