title: Binding a DynamicResource
body: <p>I'm trying to use a MultiBinding as the ItemsSource for a ListBox, and I want to bind a couple of collections to the MultiBinding.  The collections aren't populated until after the host control (a derivation of Page) has already been instantiated.  Just after being constructed, I call a method that sets up some of the data for the Page, including these collections.</p>
  
  <p>Right now, I have something like this:</p>
  
  <pre><code>public void Setup()
  {
      var items = MyObject.GetWithID(backingData.ID); // executes a db query to populate collection  
      var relatedItems = OtherObject.GetWithID(backingData.ID);
  }
  </code></pre>
  
  <p>and I want to do something like this in XAML:</p>
  
  <pre><code>&lt;Page ...
  
    ...
  
      &lt;ListBox&gt;
          &lt;ListBox.ItemsSource&gt;
              &lt;MultiBinding Converter="{StaticResource converter}"&gt;
                  &lt;Binding Source="{somehow get items}"/&gt;
                  &lt;Binding Source="{somehow get relatedItems}"/&gt;
              &lt;/MultiBinding&gt;
          &lt;/ListBox.ItemsSource&gt;
      &lt;/ListBox&gt;
    ...
  &lt;/Page&gt;
  </code></pre>
  
  <p>I know I can't use DynamicResource in a Binding, so what can I do?</p>