title: WPF WrapPanel / ItemsControl not scrolling
body: <p>I have a wrap panel displaying items but I cant get a scroll bar to work properly any idea's whats wrong ?</p>
  
  <pre><code>       &lt;ScrollViewer&gt;
          &lt;ItemsControl Name="itemsControl"&gt;
              &lt;ItemsControl.ItemsPanel&gt;
                  &lt;ItemsPanelTemplate&gt;
                      &lt;WrapPanel ItemWidth="{Binding ElementName=sizeSlider, Path=Value}" 
                                     FlowDirection="LeftToRight"  Height="auto" Width="auto"
                                     HorizontalAlignment="Left" Name="wrapPanel1" 
                                     VerticalAlignment="Top"
                                     Margin="5"
                                 &gt;
                      &lt;/WrapPanel&gt;
                  &lt;/ItemsPanelTemplate&gt;
              &lt;/ItemsControl.ItemsPanel&gt;
          &lt;/ItemsControl&gt;
      &lt;/ScrollViewer&gt;
  &lt;/StackPanel&gt;
  </code></pre>
  
  <p></p>