Let's say I have the below xml, which is used to create my list of objects:

<Authors>

  <Author Name="A">

    <Category Name="Nonfiction">

      <Book Name="1" Length="11" Date="21"/>

      <Book Name="2" Length="12" Date="22"/>

    </Category>

    <Category Name="Fiction">

      <Book Name="3" Length="13" Date="23"/>

      <Book Name="4" Length="14" Date="24"/>

    </Category>

  </Author>

  <Author Name="B">

    <Category Name="Article">

      <Book Name="5" Length="15" Date="25"/>

    </Category>

  </Author>

</Authors>

I want a grid that looks like the below. The grid is bound to a list of Authors and each author row ("A" or "B") should be expandable/collapsable to show or hide the list of books, each category its own subsection, with each of the book properties editable.  

Is there any example showing this setup?