title: get itemscontrol reference  from item
body: <p>i need to drag items between several itemcontrols , each are bound to it's own collection 
  when i drag an item i need to know which itemscontrol it was originally dragged from . </p>
  
  <p>the draggable item template :</p>
  
  <pre><code>  &lt;DataTemplate&gt;
          &lt;Ellipse MouseDown="Ellipse_MouseDown" &gt;&lt;/Ellipse&gt;
    &lt;/DataTemplate&gt; 
  </code></pre>
  
  <p>the itemscontrols :</p>
  
  <pre><code>  &lt;ItemsControl Name="Pipe23" ItemsSource="{Binding Path=Pipes[23].Checkers}" ItemTemplate="{StaticResource PipeDataItem}"/&gt;
    &lt;ItemsControl Name="Pipe22" ItemsSource="{Binding Path=Pipes[22].Checkers}" ItemTemplate="{StaticResource PipeDataItem}"/&gt;
    &lt;ItemsControl Name="Pipe21" ItemsSource="{Binding Path=Pipes[21].Checkers}" ItemTemplate="{StaticResource PipeDataItem}"/&gt;
    &lt;ItemsControl Name="Pipe20" ItemsSource="{Binding Path=Pipes[20].Checkers}"  ItemTemplate="{StaticResource PipeDataItem}"/&gt;
  </code></pre>
  
  <p>when dragging an item on the MouseDown event i can reference the item being dragged but i also need 
  to reference the itemscontrol it was dragged from : how can this be done ?</p>
  
  <pre><code>    private void Ellipse_MouseDown(object sender, MouseButtonEventArgs e)
      {
          Ellipse ellipse = (Ellipse)sender;
          Checker checker = (Checker)ellipse.DataContext;
          //  how do i reference the itemsconrtol containing the current ellipse (item)    
      }
  </code></pre>