C# WPF: Display child nodes of selected parent node as a grid

Question

I have a xml like this:

<root>
<project name="p1">
 <row field1="31" field2="3" Name="Joe"/>
  <row field1="39" field2="3" Name="Joey"/>
  <row field1="37" field2="3" Name="Joei"/>
</project>
<project name="p2">
 <row field1="31" field2="3" Name="Joe"/>
  <row field1="39" field2="3" Name="Joey"/>
</project>
</root>

Now the listbox displays the projects. When a project is selected in listbox, a grid has to display the rows. Is it possible to do this in Xaml? Or should i do it in the code as part of listbox's selectionChanged Event?