关于WPF上下文菜单的Xaml名称范围和模板问题

除了ContextMenu上的绑定之外,下面代码中的所有内容都可以工作。这显然是由于ContextMenu位于样式内部的事实,这使得它与xaml的其余部分处于不同的名称范围中。我正在寻找一个解决方案,我将不必实例化一个ContextMenu在代码背后,因为我必须应用解决方案的应用程序包含一个非常大的ContextMenu与许多绑定。必须有一种方法在xaml中实现这一点,否则它看起来像是一个严重的疏忽。还要注意,我已经尝试使用VisualTreeHelper和LogicalTreeHelper遍历元素树,但是我无法从窗口的根元素中找到ContextMenu(这些类显然跳过了感兴趣的元素)。总之,所有的代码都在下面。这可以粘贴到visualstudio中的一个新WPF应用程序中,并且不会丢失任何内容。

下面是App.xaml.cs的代码(xaml保持不变):

using System.Windows;

namespace WpfApplication1
{
    /// <summary>
    /// Interaction logic for App.xaml
    /// </summary>
    public partial class App : Application
    {
        protected override void OnStartup(StartupEventArgs e)
        {
            base.OnStartup(e);

            WindowV windowV = new WindowV();
            WindowVM windowVM = new WindowVM();

            windowV.DataContext = windowVM;

            windowV.Show();
        }
    }
}

以下是最初的Window1的xaml:

<Window x:Class="WpfApplication1.WindowV"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:src="clr-namespace:WpfApplication1"
        Name="MainWindow"
        Title="WindowV" Height="300" Width="300">
    <Window.Resources>
        <Style TargetType="{x:Type ItemsControl}">
            <Style.Triggers>
                <DataTrigger Binding="{Binding IsLocked}" Value="true">
                    <Setter Property="ItemsSource" Value="{Binding LockedList}" />
                    <Setter Property="ItemTemplate">
                        <Setter.Value>
                            <DataTemplate>
                                <TextBlock Text="{Binding}" />
                            </DataTemplate>
                        </Setter.Value>
                    </Setter>
                </DataTrigger>
                <DataTrigger Binding="{Binding IsLocked}" Value="false">
                    <Setter Property="ItemsSource" Value="{Binding RegularList}" />
                    <Setter Property="ItemTemplate">
                        <Setter.Value>
                            <DataTemplate>
                                <TextBlock Text="{Binding}">
                                    <TextBlock.ContextMenu>
                                        <ContextMenu>
                                            <MenuItem Header="{Binding MenuItem1, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}}" />
                                            <MenuItem Header="{Binding MenuItem2, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}}" />
                                            <MenuItem Header="{Binding MenuItem3, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}}" />
                                        </ContextMenu>
                                    </TextBlock.ContextMenu>
                                </TextBlock>
                            </DataTemplate>
                        </Setter.Value>
                    </Setter>
                </DataTrigger>
            </Style.Triggers>
        </Style>
    </Window.Resources>
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="4*" />
            <RowDefinition Height="*" />
        </Grid.RowDefinitions>
        <ItemsControl Grid.Row="0" />
        <Button Name="ToggleButton"
                Grid.Row="1"
                Content="Toggle Lock"
                Click="OnToggleLock" />
    </Grid>
</Window>

以下是最初的Window1的代码:

using System.Windows;
using System.Windows.Markup;

namespace WpfApplication1
{
    /// <summary>
    /// Interaction logic for Window1.xaml
    /// </summary>
    public partial class WindowV : Window
    {
        public WindowV()
        {
            InitializeComponent();
        }

        private void OnToggleLock(object sender, RoutedEventArgs e)
        {
            if (((WindowVM)(DataContext)).IsLocked == true)
                ((WindowVM)(DataContext)).IsLocked = false;
            else
                ((WindowVM)(DataContext)).IsLocked = true;
        }
    }
}

using System.Collections.Generic;
using System.ComponentModel;

namespace WpfApplication1
{
    public class WindowVM : INotifyPropertyChanged
    {
        public string MenuItem1
        {
            get
            {
                string str = "Menu item 1";
                return str;
            }
        }
        public string MenuItem2
        {
            get
            {
                string str = "Menu item 2";
                return str;
            }
        }
        public string MenuItem3
        {
            get
            {
                string str = "Menu item 3";
                return str;
            }
        }

        public List<string> LockedList
        {
            get
            {
                List<string> list = new List<string>();
                list.Add("This items control is currently locked.");
                return list;
            }
        }
        public List<string> RegularList
        {
            get
            {
                List<string> list = new List<string>();
                list.Add("Item number 1.");
                list.Add("Item number 2.");
                list.Add("Item number 3.");
                return list;
            }
        }

        private bool _isLocked;
        public bool IsLocked
        {
            get { return _isLocked; }
            set
            {
                if (_isLocked != value)
                {
                    _isLocked = value;
                    OnPropertyChanged("IsLocked");
                }
            }
        }

        public WindowVM()
        {
            IsLocked = false;
        }

        public event PropertyChangedEventHandler PropertyChanged;
        private void OnPropertyChanged(string PropertyName)
        {
            if (PropertyChanged != null)
                PropertyChanged(this, new PropertyChangedEventArgs(PropertyName));
        }
    }
}

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