title: How to have a control fill all available space
body: <p>I have a xaml code:</p>
  
  <pre><code>&lt;Grid&gt;
      &lt;WrapPanel&gt;
      &lt;TextBox &gt;&lt;/TextBox&gt;
      &lt;Button Content="GetIt" /&gt;
      &lt;/WrapPanel&gt;
  &lt;/Grid&gt;
  </code></pre>
  
  <p>How i can to get all available space for textBox?</p>
  
  <p>i want to do something like that:</p>
  
  <blockquote>
    <p>|[____________________][GetIt]|</p>
  </blockquote>