如何在触发 Treeview 的 SelectedItemChanged 事件时聚焦两个文本框？

Question

当用户在树形视图中选择树形视图项时，我试图集中两个文本框。我正在使用 SlectedItemChanged 事件来实现这一点。我需要同时关注两个文本框。

    delegate void voiDelegate();
    private void click(object sender, RoutedPropertyChangedEventArgs<object> e)
    {
        TreeViewItem t;
        t =(TreeViewItem) tvMain.SelectedItem;
        StackPanel s = (StackPanel)t.Header;
        List<TextBlock> l = new List<TextBlock>(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();
    }  

此处的焦点仅发生在 PacketDisplay2 文本框中。
如何在两个文本框中实现焦点？ 谢谢。

Answer 1

不可能同时关注 2 个文本框。 当您调用 PacketDisplay2.Focus() 时，PacketDisplay1 控件将失去焦点。 这是窗户的设计。

阅读以下链接：https://msdn.microsoft.com/en-us/library/aa969768%28v=vs.110%29.aspx

上面写的很清楚：Keyboard focus refers to the element that is currently receiving keyboard input. There can be only one element on the whole desktop that has keyboard focus.