如何选择一个数据绑定的TreeViewItem？ [英] How to select a databound TreeViewItem?
本文介绍了如何选择一个数据绑定的TreeViewItem？的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
XAML：
< Window.Resources>
< HierarchicalDataTemplate DataType =categoryItemsSource ={Binding XPath = child :: node（）}>
< TextBlock Text ={Binding XPath = @ name}FontWeight =Bold/>
< / HierarchicalDataTemplate>
< HierarchicalDataTemplate DataType =card>
< TextBlock Text ={Binding XPath =。/ title}FontStyle =Italic/>
< / HierarchicalDataTemplate>
< XmlDataProvider x：Key =dataxmlXPath =root / cards/>
< /Window.Resources>
< TreeView Name =treeView
ItemsSource ={Binding Source = {StaticResource dataxml}，
XPath =。/ *，
UpdateSourceTrigger = PropertyChanged}
/>
CS：
code> public partial class MainWindow：Window
{
XmlDataProvider xmlDataProvider = new XmlDataProvider（）;
public MainWindow（）
{
InitializeComponent（）;
xmlDataProvider = this.FindResource（dataxml）作为XmlDataProvider;
xmlDataProvider.Source = new Uri（System.IO.Path.GetFullPath（fullPathToXml），UriKind.Absolute）;
xmlDataProvider.Refresh（）;
}
public void AddChild（）
{
XmlNode newNode = xmlDataProvider.Document.CreateElement（card）;
XmlNode selectedItem =（XmlNode）treeView.SelectedItem;
if（selectedItem！= null）
{
//将newNode作为子选项添加到所选的
selectedItem.AppendChild（newNode）;
//选择子节点（newNode）??? < =====
}
else
{
//将newNode作为子代添加到rootnode并选择它：
xmlDataProvider.Document.DocumentElement [ card]。AppendChild（newNode）;
（treeView.ItemContainerGenerator.ContainerFromItem（newNode）作为TreeViewItem）.IsSelected = true;
}
xmlDataProvider.Document.Save（fullPathToXml）;
xmlDataProvider.Refresh（）;
}
}
XML：
< root>
< settings>
....
..
< / settings>
<卡>
< category name =C1>
< card name =card1>
< question> bla< / question>
< answer> blub< / answer>
< / card>
< category name =C2>
< card name =card4>
< question> bla< / question>
< answer> blub< / answer>
< / card>
< / category>
< / category>
< card name =card2>
< question> bla< / question>
< answer> blub< / answer>
< / card>
< card name =card3>
< question> bla< / question>
< answer> blub< / answer>
< / card>
< / cards>
< / root>
解决方案
迟到了，所以我的功能不是最流畅，但它的作品！
我已经评论过一次有同样的问题; - ）
使用：
using System;
使用System.Collections.Generic;
使用System.Linq;
使用System.Windows.Controls;
使用System.Xml;
使用System.Runtime.InteropServices;
功能：
code> ///< summary>
///在TreeView中选择一个XmlNode，该数据绑定到xmlDataProvider。
///< / summary>
///< param name =treeView> TreeView的引用。< / param>
///< param name =node>要选择的节点。< / param>
public static void SelectTreeViewNode（ref TreeView treeView，XmlNode node）
{
if（treeView.HasItems）
{
//转换为xml节点
var xmlNodeList = treeView.Items.Cast< XmlNode>（）; ;
//根级别的节点？ - >选择它
如果（xmlNodeList.Contains（node））
{
（treeView.ItemContainerGenerator.ContainerFromItem（node）as TreeViewItem）.IsSelected = true;
}
else
{
//获取rootnode
XmlNode根节点= GetRootNode（node，xmlNodeList）;
//获取父节点列表
列表< XmlNode> parentNodes = new List< XmlNode>（）;
GetAllParentNodes（rootNode，node，ref parentNodes）;
parentNodes.Reverse（）;
// finaly，选择节点
SelectNode（parentNodes，node，ref treeView，null）;
}
}
}
///< summary>
///循环递归到父节点，直到找到xmlNodeList中的节点。
///如果他找不到任何东西，则返回null。
///< / summary>
///< param name =node>起始节点< / param>
///< param name =xmlNodeList>具有可能根节点的列表< / param>
///< returns>根节点< / returns>
private static XmlNode GetRootNode（XmlNode node，IEnumerable< XmlNode> xmlNodeList）
{
if（！xmlNodeList.Contains（node）&& node.ParentNode！= null）
{
return GetRootNode（node.ParentNode，xmlNodeList）;
}
else if（xmlNodeList.Contains（node））返回节点;
else return null;
}
///< summary>
///从根节点内的实际节点返回所有父节点。工作递归。
///< / summary>
///< param name =rootNode>根节点< / param>
///< param name =actualNode> startnode< / param>
///< param name =parentNodes>输出列表的rererenz< / param>
private static void GetAllParentNodes（XmlNode rootNode，XmlNode actualNode，ref List< XmlNode> parentNodes）
{
if（actualNode.ParentNode！= null&！actualNode.Equals（rootNode） ）
{
parentNodes.Add（actualNode.ParentNode）;
GetAllParentNodes（rootNode，actualNode.ParentNode，ref parentNodes）;
}
}
///< summary>
///从一个数据绑定到一个xmlDataProvider的TreeView中选择一个XmlNode。
///< / summary>
///< param name =parentNodes>列表中的所有父节点都是rootnode。< / param>
///< param name =node>要选择的节点。< / param>
///< param name =treeView> TreeView的引用。< / param>
///< param name =item>递归的变量。< / param>
private static void SelectNode（List< XmlNode> parentNodes，XmlNode node，ref TreeView treeView，[可选，DefaultParameterValue（null）] TreeViewItem项）
{
if（parentNodes.Count> 0 ）
{
TreeViewItem tvItem;
if（item！= null）
tvItem = item.ItemContainerGenerator.ContainerFromItem（parentNodes.First（））作为TreeViewItem;
else
tvItem = treeView.ItemContainerGenerator.ContainerFromItem（parentNodes.First（））作为TreeViewItem;
parentNodes.RemoveAt（0）;
SelectNode（parentNodes，node，ref treeView，tvItem）;
}
else if（item！= null）
{
（item.ItemContainerGenerator.ContainerFromItem（node）as TreeViewItem）.IsSelected = true;
}
}
I have a XML databound to a TreeView with a XmlDataProvider. If i add a subnode to the XML the TreeView shows it, but how can i select this item?
XAML:
<Window.Resources>
<HierarchicalDataTemplate DataType="category" ItemsSource="{Binding XPath=child::node()}">
<TextBlock Text="{Binding XPath=@name}" FontWeight="Bold" />
</HierarchicalDataTemplate>
<HierarchicalDataTemplate DataType="card">
<TextBlock Text="{Binding XPath=./title}" FontStyle="Italic" />
</HierarchicalDataTemplate>
<XmlDataProvider x:Key="dataxml" XPath="root/cards"/>
</Window.Resources>
<TreeView Name="treeView"
ItemsSource="{Binding Source={StaticResource dataxml},
XPath=./*,
UpdateSourceTrigger=PropertyChanged}"
/>
CS:
public partial class MainWindow : Window
{
XmlDataProvider xmlDataProvider = new XmlDataProvider();
public MainWindow()
{
InitializeComponent();
xmlDataProvider = this.FindResource("dataxml") as XmlDataProvider;
xmlDataProvider.Source = new Uri(System.IO.Path.GetFullPath(fullPathToXml), UriKind.Absolute);
xmlDataProvider.Refresh();
}
public void AddChild()
{
XmlNode newNode = xmlDataProvider.Document.CreateElement("card");
XmlNode selectedItem = (XmlNode)treeView.SelectedItem;
if (selectedItem != null)
{
//add the newNode as child to the selected
selectedItem.AppendChild(newNode);
//select the childnode (newNode) ????? <=====
}
else
{
//add the newNode as child to the rootnode and select it:
xmlDataProvider.Document.DocumentElement["cards"].AppendChild(newNode);
(treeView.ItemContainerGenerator.ContainerFromItem(newNode) as TreeViewItem).IsSelected = true;
}
xmlDataProvider.Document.Save(fullPathToXml);
xmlDataProvider.Refresh();
}
}
XML:
<root>
<settings>
....
..
</settings>
<cards>
<category name="C1">
<card name="card1">
<question>bla</question>
<answer>blub</answer>
</card>
<category name="C2">
<card name="card4">
<question>bla</question>
<answer>blub</answer>
</card>
</category>
</category>
<card name="card2">
<question>bla</question>
<answer>blub</answer>
</card>
<card name="card3">
<question>bla</question>
<answer>blub</answer>
</card>
</cards>
</root>
解决方案
It is late, so my functions arent the smoothest, but it works! I have comment it for all that once have the same problem ;-)
Usings:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Controls;
using System.Xml;
using System.Runtime.InteropServices;
Function:
/// <summary>
/// Select a XmlNode in a TreeView that is databound to a xmlDataProvider.
/// </summary>
/// <param name="treeView">A referenz to the TreeView.</param>
/// <param name="node">The node to select.</param>
public static void SelectTreeViewNode(ref TreeView treeView, XmlNode node)
{
if (treeView.HasItems)
{
//cast to xml-nodes
var xmlNodeList = treeView.Items.Cast<XmlNode>(); ;
//node at root level? -> select it
if (xmlNodeList.Contains(node))
{
(treeView.ItemContainerGenerator.ContainerFromItem(node) as TreeViewItem).IsSelected = true;
}
else
{
//get rootnode
XmlNode rootNode = GetRootNode(node, xmlNodeList);
//get a list of parent nodes
List<XmlNode> parentNodes = new List<XmlNode>();
GetAllParentNodes(rootNode, node, ref parentNodes);
parentNodes.Reverse();
//finaly, select the node
SelectNode(parentNodes, node, ref treeView, null);
}
}
}
/// <summary>
/// Goes recursiv down the parent nodes until he finds a node that is in the xmlNodeList.
/// Returns null if he can´t find anything.
/// </summary>
/// <param name="node">The start node.</param>
/// <param name="xmlNodeList">A list with possible rootnodes.</param>
/// <returns>The rootnode</returns>
private static XmlNode GetRootNode(XmlNode node, IEnumerable<XmlNode> xmlNodeList)
{
if (!xmlNodeList.Contains(node) && node.ParentNode != null)
{
return GetRootNode(node.ParentNode, xmlNodeList);
}
else if (xmlNodeList.Contains(node)) return node;
else return null;
}
/// <summary>
/// Returns all parent nodes from the actual node within the rootNode. Works recursiv.
/// </summary>
/// <param name="rootNode">The rootnode.</param>
/// <param name="actualNode">The startnode</param>
/// <param name="parentNodes">The rererenz to the outputlist</param>
private static void GetAllParentNodes(XmlNode rootNode, XmlNode actualNode, ref List<XmlNode> parentNodes)
{
if (actualNode.ParentNode != null && !actualNode.Equals(rootNode))
{
parentNodes.Add(actualNode.ParentNode);
GetAllParentNodes(rootNode, actualNode.ParentNode, ref parentNodes);
}
}
/// <summary>
/// Select a XmlNode from a TreeView that is databound to a xmlDataProvider.
/// </summary>
/// <param name="parentNodes">All the parent nodes, first in the list is the rootnode.</param>
/// <param name="node">The node to select.</param>
/// <param name="treeView">A referenz to the TreeView.</param>
/// <param name="item">Variable for the recursion.</param>
private static void SelectNode(List<XmlNode> parentNodes, XmlNode node, ref TreeView treeView, [Optional, DefaultParameterValue(null)] TreeViewItem item)
{
if (parentNodes.Count > 0)
{
TreeViewItem tvItem;
if (item != null)
tvItem = item.ItemContainerGenerator.ContainerFromItem(parentNodes.First()) as TreeViewItem;
else
tvItem = treeView.ItemContainerGenerator.ContainerFromItem(parentNodes.First()) as TreeViewItem;
parentNodes.RemoveAt(0);
SelectNode(parentNodes, node, ref treeView, tvItem);
}
else if (item != null)
{
(item.ItemContainerGenerator.ContainerFromItem(node) as TreeViewItem).IsSelected = true;
}
}
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