WPF TreeView 选择事件执行两次,获取TreeView的父节点的解决方法

时间:2022-05-03
本文章向大家介绍WPF TreeView 选择事件执行两次,获取TreeView的父节点的解决方法,主要内容包括1.TreeView选择事件执行两次、2.Treeview获取父节点、基本概念、基础应用、原理机制和需要注意的事项等,并结合实例形式分析了其使用技巧,希望通过本文能帮助到大家理解应用这部分内容。

1.TreeView选择事件执行两次

Very often, we need to execute some code in SelectedItemChanged depending on the selected TreeViewItem. ButSelectedItemChanged is called twice. This is due to stealing focus from the main window, which is screwing something up.

What we have to do to avoid this is simply delay the call to our code, i.e., MyFunction() which we need to execute inSelectedItemChanged. Here's a workaround which delays the call to open the new window until the item selection code finishes up:

private delegate void NoArgDelegate();
 
void Window1_SelectedItemChanged(object sender, RoutedPropertyChangedEventArgs<object> e)
{
  Dispatcher.BeginInvoke(DispatcherPriority.Background, 
        (NoArgDelegate)delegate { MyFunction(); });
}

2.Treeview获取父节点

   private void treeView1_SelectedItemChanged(object sender, RoutedPropertyChangedEventArgs<object> e)
        {
            //节点(是子节点或者是根节点)
            TreeViewItem item = treeView1.SelectedItem as TreeViewItem;
 
            //获取父节点
            TreeViewItem parent = item.Parent as TreeViewItem;
            //判断父节点是否存在
            if (parent != null) {
                //显示父节点信息,这里显示 Header 信息
                MessageBox.Show("父节点的Header:" + parent.Header.ToString());
            } else {
                MessageBox.Show("没有父节点!");
            }
 
        }