How to bind to two properties in different sources?
<p>I'd like to have a combobox whose ItemsSource is fed from a posteViewSource and it's SelectedItem to be bound to the idPoste field of the table that is linked to superviseurViewSource.</p>

<pre><code>&lt;Window.Resources&gt;
    &lt;local:StagesBDDataSet x:Key="stagesBDDataSet"/&gt;
    &lt;CollectionViewSource x:Key="superviseurViewSource" Source="{Binding Superviseur, Source={StaticResource stagesBDDataSet}}"/&gt;
    &lt;CollectionViewSource x:Key="posteViewSource" Source="{Binding Poste, Source={StaticResource stagesBDDataSet}}"/&gt;
&lt;/Window.Resources&gt;
</code></pre>

<p>Here's my combobox definition:</p>

<pre><code>        &lt;ComboBox x:Name="idPosteComboBox" DataContext="{StaticResource posteViewSource}" ItemsSource="{Binding}" Height="23" Width="120" DisplayMemberPath="idPoste" /&gt;
</code></pre>

<p>The combobox is in a grid whose DataContext is set to : {StaticResource superviseurViewSource}. The binding with the items works perfectly, but I don't know if it's possible to have another DataContext for the SelectedItem property. Any hints would be appreciated, thanks.</p>