title: How to stretch Grid within a Viewbox
body: <p>I would like to stretch  <code>Grid</code> within a <code>Viewbox</code>. The code I have god does not work properly. Any clue?</p>
  
  <pre><code> &lt;Viewbox HorizontalAlignment="Stretch" VerticalAlignment="Stretch"&gt;
          &lt;Grid HorizontalAlignment="Stretch" VerticalAlignment="Stretch"&gt;
           &lt;Grid.ColumnDefinitions&gt;
                  &lt;ColumnDefinition Width="Auto"&gt;&lt;/ColumnDefinition&gt;
              &lt;/Grid.ColumnDefinitions&gt;
              &lt;Grid.RowDefinitions&gt;
                  &lt;RowDefinition Height="*"&gt;&lt;/RowDefinition&gt;
                  &lt;RowDefinition Height="Auto"&gt;&lt;/RowDefinition&gt;
              &lt;/Grid.RowDefinitions&gt;
   &lt;/Grid&gt;
  &lt;/Viewbox&gt;
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/2dHMk.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/2dHMk.png" alt="enter image description here"></a></p>