title: RelativeSource binding from a ToolTip or ContextMenu
body: <p>What am I doing wrong here?:</p>
  
  <pre><code> &lt;GridViewColumn&gt;
      &lt;GridViewColumn.CellTemplate&gt;
         &lt;DataTemplate&gt;
            &lt;Button&gt;
              &lt;Button.ToolTip&gt;
                &lt;TextBlock Text="{Binding Path=Title, RelativeSource={RelativeSource AncestorType=Window}}" /&gt;
  </code></pre>
  
  <p>That's just a simplified example, that doesn't work anyway :) 
  Actually I need to get a value from another property that is in scope of the Window's DataContext.</p>
  
  <p>Help me pls.</p>