title: How to Focus Two Text Boxes as SelectedItemChanged event of Treeview is triggerd?
body: <p>I am trying to focus the two text boxes as the user selects the treeview item in treeview. I am using a SlectedItemChanged event to achieve this. I need to focus both the text boxes at the same time.</p>
  
  <pre><code>    delegate void voiDelegate();
      private void click(object sender, RoutedPropertyChangedEventArgs&lt;object&gt; e)
      {
          TreeViewItem t;
          t =(TreeViewItem) tvMain.SelectedItem;
          StackPanel s = (StackPanel)t.Header;
          List&lt;TextBlock&gt; l = new List&lt;TextBlock&gt;(3);
          foreach (TextBlock children in s.Children)
          {
              l.Add(children);
          }
          string ch = l[3].Text;
          string[] sp = ch.Split('-');
          int te = Convert.ToByte(sp[1]) - Convert.ToByte(sp[0]) + 1;
          PacketDisplay1.SelectionStart = PacketDisplay2.SelectionStart = Convert.ToByte(sp[0]);
          PacketDisplay1.SelectionLength= PacketDisplay2.SelectionLength = te;
          voiDelegate giveFocusDelegate = new voiDelegate(giveFocus);
          Dispatcher.BeginInvoke(giveFocusDelegate, new object[] { });
  
      }
      private void giveFocus()
      {
          PacketDisplay1.Focus();
          PacketDisplay2.Focus();
      }  
  </code></pre>
  
  <p>Here focus is happening only in PacketDisplay2 text box.<br>
   how can I achieve Focus in Both text boxes?
   thanks.</p>