title: WPF Expander expand behind the grid row
body: <p>I have expander control in grid row. And I change the expander size on the expander button click to maximize the expander size.  And on the collapse status I minimize the expander size. The problem is the expander expands under the grid row.
  Is there is any way to make the expander expand on top of any control?</p>
  
  <pre><code>&lt;Grid AllowDrop="False"&gt;
      &lt;Grid.RowDefinitions&gt;
          &lt;RowDefinition Height="199*" /&gt;
          &lt;RowDefinition Height="175*" /&gt;
      &lt;/Grid.RowDefinitions&gt;
      &lt;Grid Height="60" HorizontalAlignment="Left" Margin="21,26,0,0" Name="grid1" VerticalAlignment="Top" Width="550" Background="#FFE59E9E"&gt;
          &lt;Label Content="Label" Height="28" HorizontalAlignment="Left" Margin="62,113,0,0" Name="label1" VerticalAlignment="Top" /&gt;
          &lt;TextBox Height="23" HorizontalAlignment="Left" Margin="130,115,0,0" Name="textBox1" VerticalAlignment="Top" Width="120" Background="#FF2B1313" /&gt;
      &lt;/Grid&gt;
      &lt;Expander Name="exp" Expanded="exp_Expanded" Background="#FF3383A7" BorderThickness="4" BorderBrush="{x:Null}" FlowDirection="LeftToRight" Collapsed="exp_Collapsed" ExpandDirection="Left" Height="49" VerticalAlignment="Top" HorizontalAlignment="Right" Width="602" Margin="0,139,237,0"&gt;
          &lt;DataGrid AutoGenerateColumns="False" Height="105" Name="dataGrid1" Width="200" HorizontalContentAlignment="Center" VerticalAlignment="Center" /&gt;
      &lt;/Expander&gt;
  &lt;/Grid&gt;
  
  
    private void exp_Expanded(object sender, RoutedEventArgs e)
      {
          var exp = (Expander) sender;
          //grid1.Width = 550;
         // grid1.Height = 40;
  
            exp.Width = 602;
           exp.Height = 300;
  
  
      }
  
      private void exp_Collapsed(object sender, RoutedEventArgs e)
      {
          var exp = (Expander)sender;
  
         // grid1.Height = 500;
          exp.Width = 602;
          exp.Height = 49;
  
  
  
      }
  </code></pre>