wpf listView with ContextMenu 不使用数据绑定显示数据

Question

I have a problem with my List View.

It shows all the elements that I add to the ObservableCollection binded to it, just how it's supposed to work, but when I right-click any of it's elements, the bindings won't work and it won't display the data as I intend it to do.

I created another WPF project to show you the problem more clearly.

Here's my wpf code:

<Window x:Class="WpfApp2.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    Title="MainWindow" Height="350" Width="525">
<Grid>
    <ListView x:Name="listViewWithContextMenu" ItemsSource="{Binding  Path=CollectionOfThings}"  HorizontalAlignment="Stretch"  VerticalAlignment="Stretch">
        <ListView.View>
            <GridView>
                <GridViewColumn Width="120" Header="Name" DisplayMemberBinding="{Binding Name}"/>
                <GridViewColumn Width="120" Header="Quantity" DisplayMemberBinding="{Binding Quantity}"/>
            </GridView>
        </ListView.View>
        <ListView.ContextMenu>
            <ContextMenu>
                <StackPanel Orientation="Horizontal">
                    <StackPanel Orientation="Vertical" Margin="3">
                        <StackPanel Orientation="Horizontal">
                            <TextBlock Text="Name: "></TextBlock>
                            <TextBlock Text="{Binding Name}"></TextBlock>
                        </StackPanel>
                        <StackPanel Orientation="Horizontal">
                            <TextBlock Text="Quantity: "></TextBlock>
                            <TextBlock Text="{Binding Quantity}"></TextBlock>
                        </StackPanel>
                    </StackPanel>
                </StackPanel>
            </ContextMenu>
        </ListView.ContextMenu>
    </ListView>
</Grid>

and the c# code behind it:

using System.Windows;
using System.Collections.ObjectModel;

namespace WpfApp2
{
public partial class MainWindow : Window
{
    public ObservableCollection<DataOfThing> CollectionOfThings = new ObservableCollection<DataOfThing>();
    public MainWindow()
    {
        InitializeComponent();

        CollectionOfThings.Add(new DataOfThing() { Name = "Some Name", Quantity = 2 });
        CollectionOfThings.Add(new DataOfThing() { Name = "Some Other Name", Quantity = 3 });
        CollectionOfThings.Add(new DataOfThing() { Name = "Strange Name", Quantity = 1 });

        listViewWithContextMenu.ItemsSource = CollectionOfThings;
    }
}

public class DataOfThing
{
    public string Name { get; set; }
    public int Quantity { get; set; }

}

}

And here's what I get:

Answer 1

What happens is that ContextMenu is not in the same visual tree of your ListView (or any other control). It is completely separated from your Window element tree and that's why it gets lost on binding.

I got a solution that might not be the most beautiful but works :)

Set a ContextMenuOpening event to your ListView:

<ListView x:Name="listViewWithContextMenu" ItemsSource="{Binding Path=CollectionOfThings}"  HorizontalAlignment="Stretch"  VerticalAlignment="Stretch" ContextMenuOpening="listViewWithContextMenu_ContextMenuOpening">

And in your codebehind, do:

private void listViewWithContextMenu_ContextMenuOpening(object sender, ContextMenuEventArgs e)
{
    var list = sender as ListView;
    list.ContextMenu.DataContext = list.SelectedItem;
}