C# 获取视图模型内的TreeView SelectedItem

我正在尝试获取ViewModel中选定的TreeView节点

内部Xaml

<Grid>
        <TreeView ItemsSource="{Binding TreeViewModel.TreeData}">
            <TreeView.Resources>
                <HierarchicalDataTemplate ItemsSource="{Binding  GroupTables}" DataType="{x:Type tbl:StaticTablesGroup}">
                    <Label Content="{Binding Name}"/>

                </HierarchicalDataTemplate>

                <DataTemplate DataType="{x:Type tbl:GroupTable}">
                    <Label Content="{Binding Name}"/>
                </DataTemplate>
            </TreeView.Resources>

            <TreeView.ItemContainerStyle>
                <Style TargetType="TreeViewItem">
                    <Setter Property="IsSelected" Value="{Binding IsSelected, Mode=TwoWay}" />
                    <Style.Triggers>
                        <Trigger Property="IsSelected" Value="True">
                            <Setter Property="FontWeight" Value="Bold" />
                        </Trigger>
                    </Style.Triggers>
                </Style>
            </TreeView.ItemContainerStyle>
        </TreeView>        
    </Grid>

内部模型

public class TreeTablesViewModel : ViewModelBase
    {
        private TablesXML _tables;
        public TreeTablesViewModel()
        {

            _tables = Deserialize.GuymasterXml();
        }

        public List<StaticTablesGroup> TreeData
        {
            get
            {
                return _tables.StaticTablesGroups;
            }

            set
            {
                _tables.StaticTablesGroups = value;
                OnPropertyChanged("TreeData");
            }
        }       
    }

public类TreeTablesViewModel:ViewModelBase
{
私有表xml_表；
公共树etablesviewmodel（）
{
_tables=反序列化.GuymasterXml（）；
}
公共列表树数据
{
得到
{
返回_tables.statictablegroups；
}
设置
{
_tables.statictablegroups=值；
不动产变更（“TreeData”）；
}
}       
}

最后是数据类

[XmlRoot("Tables")]
    public class TablesXML
    {
        public TablesXML()
        {
            StaticTablesGroups = new List<StaticTablesGroup>();
        }


        [XmlArray("StaticGroups")]
        [XmlArrayItem("StaticGroup", typeof(StaticTablesGroup))]
        public List<StaticTablesGroup> StaticTablesGroups { get; set; }

    }

    public class StaticTablesGroup
    {
        public StaticTablesGroup()
        {
            GroupTables = new List<GroupTable>();
        }

        [XmlAttribute("Name")]
        public string Name { get; set; }

        //[XmlArray("StaticGroup")]
        [XmlElement("Table", typeof(GroupTable))]
        public List<GroupTable> GroupTables { get; set; }


    }


    public class GroupTable
    {

        [XmlElement("TableName")]
        public string Name { get; set; }
        [XmlElement("TableTag")]
        public string Tag { get; set; }

        private bool _isSelected;
        public bool IsSelected
        {
            get { return _isSelected; }
            set
            {
                if (_isSelected != value)
                {
                    _isSelected = value;

                }
            }
        }
    }

[XmlRoot（“表”）]
公共类表XML
{
公共表XML（）
{
StaticTablesGroups=新列表（）；
}
[XmlArray（“静态组”）]
[XmlArrayItem（“StaticGroup”，typeof（statictablegroup））]
公共列表组{get；set；}
}
公共类组
{
公共表组（）
{
GroupTables=新列表（）；
}
[XmlAttribute（“名称”）]
公共字符串名称{get；set；}
//[XmlArray（“StaticGroup”）]
[XmlElement（“表格”，类型（GroupTable））]
公共列表组表{get；set；}
}
公共类分组表
{
[XmlElement（“表名”）]
公共字符串名称{get；set；}
[XmlElement（“TableTag”）]
公共字符串标记{get；set；}
私立学校当选；
公选学校
{
获取{return}isSelected；}
设置
{
如果（_isSelected！=值）
{
_isSelected=值；
}
}
}
}

选择Treeview节点后，将在GroupTable或StaticTablesGroup中引发IsSelected。 如何在TreeTablesViewModel中获取所选节点

---

谢谢

获取TreeViewItem（我认为这是您的意思）的最简单方法是从树的选择处理程序中的项目容器生成器获取它

    private void treeView_SelectedItemChanged(object sender, RoutedPropertyChangedEventArgs<object> e)
    {
        TreeView tv = e.Source as TreeView;
        TreeViewItem tvi = tv.ItemContainerGenerator.ContainerFromItem(e.NewValue) as TreeViewItem;
    }

private void treeView\u SelectedItemChanged（对象发送方，RoutedPropertyChangedEventArgs e）
{
TreeView tv=e.来源为TreeView；
TreeViewItem tvi=tv.ItemContainerGenerator.ContainerFromItem（e.NewValue）作为TreeViewItem；
}

XAML

    <TreeView ItemsSource="{Binding TreeViewModel.TreeData}" SelectedItemChanged="treeView_SelectedItemChanged" >

---

从这里我想您可以进入视图模型。

您不应该试图在视图模型内操纵视图对象（TreeView、TreeView、TreeNode等）。视图模型必须仅操作业务/poco对象

如果要检索与所选可视对象（TreeViewItem或node）对应的基础业务对象，可以使用如下行为：

public class TreeviewSelectedItemTracker
{
    public static TreeTablesViewModel GetSelectedItemHolder(DependencyObject obj)
    {
        return (TreeTablesViewModel)obj.GetValue(SelectedItemHolderProperty);
    }

    public static void SetSelectedItemHolder(DependencyObject obj, TreeTablesViewModel value)
    {
        obj.SetValue(SelectedItemHolderProperty, value);
    }

    public static readonly DependencyProperty SelectedItemHolderProperty =
        DependencyProperty.RegisterAttached("SelectedItemHolder", typeof(TreeTablesViewModel), typeof(TreeviewSelectedItemTracker), new PropertyMetadata(null, OnSelectedChanged));

    private static void OnSelectedChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        TreeView tv = (TreeView)d;
        tv.Loaded += Tv_Loaded;
    }

    private static void Tv_Loaded(object sender, RoutedEventArgs e)
    {
        TreeView tv = (TreeView)sender;
        tv.Loaded -= Tv_Loaded;
        tv.Unloaded += Tv_Unloaded;
        tv.SelectedItemChanged += Tv_SelectedItemChanged;
    }

    private static void Tv_Unloaded(object sender, RoutedEventArgs e)
    {
        TreeView tv = (TreeView)sender;

        tv.Unloaded -= Tv_Unloaded;
        tv.SelectedItemChanged -= Tv_SelectedItemChanged;
    }

    private static void Tv_SelectedItemChanged(object sender, RoutedPropertyChangedEventArgs<object> e)
    {
        TreeView tv = (TreeView)sender;

        var cotr = GetSelectedItemHolder(tv);

        cotr.SelectedItem = tv.SelectedItem;

    }
}

---

我尝试不使用MVVM模式来添加代码。谢谢您的回复。我将Selecteditem属性添加到TreeTablesViewModel:private object\u Selecteditem；公共对象SelectedItem{get{return{U SelectedItem；}set{U SelectedItem=value；OnPropertyChanged（“SelectedItem”）；}}但是，viewModel中的SelectedItem永远不会执行。我做错了什么。在XAML中：是否尝试在行为中的SelectedItemChanged处理程序中放置断点，以查看事件是否引发？Tv_SelectedItemChanged事件从未引发。这意味着对“SelectedItemHolder”属性的绑定未绑定到正确的对象。绑定不能指向SelectEditeProperty本身，而是指向视图模型：vm:TreeviewSelectedItemTracker.SelectedItemHolder=“{binding TreeViewModel}”

<TreeView ItemsSource="{Binding TreeViewModel.TreeData}" local:TreeviewSelectedItemTracker.SelectedItemHolder="{Binding}"/>