title: Find control inside Listbox.ItemTemplate (WPF C#)
body: <p>I have some problems finding the right <code>TextBlock</code> control inside a <code>StackPanel</code>. 
  My markup:</p>
  
  <pre><code>&lt;ListBox Name="lstTimeline" ItemContainerStyle="{StaticResource TwItemStyle}"
           MouseDoubleClick="lstTimeline_MouseDoubleClick"&gt;
      &lt;ListBox.ItemTemplate&gt;
          &lt;DataTemplate&gt;
              &lt;DockPanel MaxWidth="{Binding ElementName=lstTimeline, Path=ActualWidth}"&gt;
                  &lt;Border Margin="10" DockPanel.Dock="Left"  BorderBrush="White"
                          BorderThickness="1" Height="48" Width="48" HorizontalAlignment="Center"&gt;
                      &lt;Image Source="{Binding ThumbNail, IsAsync=True}" Height="48" Width="48" /&gt;
                  &lt;/Border&gt;
                  &lt;StackPanel Name="stkPanel" Margin="10" DockPanel.Dock="Right"&gt;
                      &lt;TextBlock Text="{Binding UserName}" FontWeight="Bold" FontSize="18" /&gt;
                      &lt;TextBlock Text="{Binding Text}" Margin="0,4,0,0" FontSize="14"
                                 Foreground="#c6de96" TextWrapping="WrapWithOverflow" /&gt;
                      &lt;TextBlock Text="{Binding ApproximateTime}" FontSize="14"
                                 FontFamily="Georgia" FontStyle="Italic" Foreground="#BBB" /&gt;
                      &lt;TextBlock Text="{Binding ScreenName}" Name="lblScreenName"  FontSize="14"
                                 FontFamily="Georgia" FontStyle="Italic" Foreground="#BBB"
                                 Loaded="lblScreenName_Loaded" /&gt;
                  &lt;/StackPanel&gt;
              &lt;/DockPanel&gt;
          &lt;/DataTemplate&gt;
      &lt;/ListBox.ItemTemplate&gt;
  &lt;/ListBox&gt;
  </code></pre>
  
  <p>My double click code:</p>
  
  <pre><code>private void lstTimeline_MouseDoubleClick(object sender, MouseButtonEventArgs e)
  {
      ListBoxItem lbi = (lstTimeline.SelectedItem as ListBoxItem);
  
      StackPanel item = lbi.FindName("stkPanel") as StackPanel;
      if (item != null)
          MessageBox.Show("StackPanel null");
      TextBlock textBox = item.FindName("lblScreenName") as TextBlock;
      if (textBox != null)
          MessageBox.Show("TextBlock null");
  
      MessageBox.Show(textBox.Text);
  }
  </code></pre>
  
  <p>But the <code>StackPanel</code> is null.  How do find the right <code>TextBlock</code> in <code>SelectedItem</code>?</p>
  
  <p>Thanks for your help.</p>