title: Draw line equal to page width in wp8
body: <p>I am using <code>Line</code> to draw line in my wp8 app, but when I change the page orientation, It's always the same width. I know the line width is static set to 480, how can I make it Auto to fit the page in both orientations. I'm using the line inside <code>ListBox</code> ItemTemplate.</p>
  
  <pre><code>&lt;ListBox x:Name="lsbReadingChapter" Style="{StaticResource ListBoxStyle1}" 
           Grid.Row="1" DoubleTap="lsbReadingChapter_DoubleTap"&gt;
      &lt;ListBox.ItemTemplate&gt;
          &lt;DataTemplate&gt;
            ....
            &lt;Line X1="0" X2="480" Y1="0" Y2="0" VerticalAlignment="Bottom"
                  StrokeThickness="1" Stroke="LightGray" /&gt;
          &lt;/DataTemplate&gt;
  
      &lt;/ListBox.ItemTemplate&gt;
  &lt;/ListBox&gt;
  </code></pre>
  
  <p>How to draw the line to auto fit the page in both orientations?</p>