Привязка ObservableCollection к ListView с использованием MVVM

У меня возникла проблема при попытке привязать Observable Collection к элементу управления ListView. Я не уверен, что мой шаблон проектирования верен. Я храню список пользователей в модели представления как ObservableCollection. Затем я устанавливаю источник ListView в качестве этой коллекции. Однако когда я делаю ListView.ItemTemplate, ему не нравится следующее:

<TextBlock Text = "{x:Bind Username}" Grid.Column = "0"></TextBlock>"

Пишет, что имя пользователя не найдено в UserViewModel.

Если я изменю DataTemplate на использование модели, идентификатор/имя пользователя будет работать, но RelayCommand — нет.

Я использую WinUi 3, Entity Framework Core и набор инструментов сообщества MVVM.

Это код, который у меня есть до сих пор:

Модель

public partial class User: ObservableObject
{
    public int Id { get; set; }

    [ObservableProperty]
    private string _username = string.Empty;
    
    partial void OnUsernameChanged(string? oldValue, string newValue)
    {
        Debug.WriteLine("Username changed");        
    }
}

Посмотреть модель

public partial class UserViewModel : ObservableObject
{
    RecipeDBContext context;

    private ObservableCollection<User> _users;        
    public ObservableCollection<User> Users
    {
        get { return _users; }
        set
        {
            if (_users != value)
            {
                if (_users != null)
                {
                    _users.CollectionChanged -= OnCollectionChanged;
                }

                _users = value;

                if (_users != null)
                {
                    _users.CollectionChanged += OnCollectionChanged;
                }
            }
        }
    }
    

    public UserViewModel() 
    {
        context = new RecipeDBContext();
        _users = new ObservableCollection<User>();
        UpdateUsers(context.User.ToList());

    }

    public void UpdateUsers(List<User> users)
    {
        _users.Clear();
        foreach (User user in users)
        {
            Users.Add(user);
        }
    }

    void OnCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
    {
        if (e.NewItems != null)
        {
            foreach (User newItem in e.NewItems)
            {                                
                context.User.Add(newItem);                
            }
        }

        if (e.OldItems != null)
        {
            foreach (User oldItem in e.OldItems)
            {                
                context.User.Remove(oldItem);                
            }
        }
        context.SaveChanges();
    }

    [RelayCommand]
    public void DeleteUser(object o)
    {
        Debug.WriteLine("Called Delete User");
        if (o != null)
        {
            int id = int.Parse(o.ToString());
            
            using (context)
            {
                try
                {
                    context.User.Remove(new User() { Id = id });
                    context.SaveChanges();
                }
                catch (Exception ex)
                {
                    if (!context.User.Any(i => i.Id == id))
                    {                        
                        return;
                    }
                    else
                    {
                        throw ex;
                    }
                }
            }
        }
    }

    [RelayCommand]
    public void AddUser(object o)
    {
        if (o != null)
        {
            string username=o as string;
            if (username != String.Empty)
            {
                using (context)
                {
                    var user = new User()
                    {                        
                        Username = username,
                    };                    
                    context.User.Add(user);                                       
                    context.SaveChanges();
                }
            }
        }                                
    }

    [RelayCommand]
    private void ModifyName(object o)
    {
        string oldName = "fred";
        if (o != null)
        {
            string newUsername = o as string;
            if (newUsername != String.Empty)
            {
                for (int i = Users.Count - 1; i >= 0; i--)
                {                    
                    if (Users[i].Username == oldName)
                    {
                        Users[i].Username = newUsername;
                        context.SaveChanges();
                    }
                }
            }
            else
            {
                
            }
        }
    }
}

Вид

<Page
    x:Class = "Test.Views.UserPage"
    xmlns = "http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x = "http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local = "using:Test.Views"
    xmlns:d = "http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc = "http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:vm = "using:Test.ViewModels"    
    mc:Ignorable = "d"    
    xmlns:m = "using:Test.Models">
    
    <Page.DataContext>
        <vm:UserViewModel x:Name = "ViewModel"/>
    </Page.DataContext>

    <Grid>

        <Grid.RowDefinitions>
            <RowDefinition Height = "0.2*"></RowDefinition>
            <RowDefinition Height = "Auto"></RowDefinition>
            <RowDefinition Height = "Auto"></RowDefinition>
            <RowDefinition Height = "Auto"></RowDefinition>
            <RowDefinition Height = "Auto"></RowDefinition>
            <RowDefinition Height = "Auto"></RowDefinition>
            <RowDefinition Height = "Auto"></RowDefinition>
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width = "0.3*"></ColumnDefinition>
            <ColumnDefinition Width = "0.3*"></ColumnDefinition>
            <ColumnDefinition Width = "0.3*"></ColumnDefinition>
        </Grid.ColumnDefinitions>
        <Border BorderThickness = "1" BorderBrush = "Black" />
        <TextBlock FontSize = "30" Grid.Row = "0" Grid.Column = "0">LOGIN</TextBlock>
        <TextBlock Grid.Row = "1" Grid.Column = "0">User</TextBlock>
        <ListView x:Name = "usersListView" Grid.Row = "1" Grid.Column = "1" ItemsSource = "{x:Bind ViewModel.Users, Mode=TwoWay}">
            <ListView.Header>
                <Grid>
                    <Grid.ColumnDefinitions>
                        <ColumnDefinition Width = "0.3*"></ColumnDefinition>
                        <ColumnDefinition Width = "0.3*"></ColumnDefinition>
                        <ColumnDefinition Width = "0.3*"></ColumnDefinition>
                    </Grid.ColumnDefinitions>
                    <ListViewHeaderItem  Grid.Column = "0">
                        <TextBlock>Username</TextBlock>
                    </ListViewHeaderItem>
                    <ListViewHeaderItem  Grid.Column = "1">
                        <TextBlock>Recipes</TextBlock>
                    </ListViewHeaderItem>
                    <ListViewHeaderItem  Grid.Column = "2">
                        <TextBlock>Delete</TextBlock>
                    </ListViewHeaderItem>
                </Grid>
            </ListView.Header>

            <ListView.ItemTemplate>
                <DataTemplate x:DataType = "vm:UserViewModel">
                    <Grid>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width = "0.3*"></ColumnDefinition>
                            <ColumnDefinition Width = "0.3*"></ColumnDefinition>
                            <ColumnDefinition Width = "0.3*"></ColumnDefinition>
                        </Grid.ColumnDefinitions>
                        <TextBlock Text = "{x:Bind Username}" Grid.Column = "0"></TextBlock>
                        <Button Grid.Column = "2" Command = "{x:Bind DeleteUserCommand}" CommandParameter = "{x:Bind Id}">X</Button>
                    </Grid>
                </DataTemplate>
            </ListView.ItemTemplate>
        </ListView>
        <Button x:Name = "loginUserBtn" Click = "loginUserButton_Click" Grid.Row = "2" Grid.Column = "1">Login</Button>

        <TextBlock Grid.Row = "3" Grid.Column = "0" FontSize = "30">New User</TextBlock>
        <TextBlock Grid.Row = "4" Grid.Column = "0">Name</TextBlock>
        <TextBox x:Name = "newUserName" Grid.Row = "4" Grid.Column = "1"></TextBox>
        <Button x:Name = "addUserBtn" Click = "addUserButton_Click" Grid.Row = "5" Grid.Column = "1">Add User</Button>
        <Button x:Name = "addUserBtn1" Command = "{x:Bind ViewModel.AddUserCommand}" CommandParameter = "{Binding Text, ElementName=newUserName}" Grid.Row = "5" Grid.Column = "2">Add User1</Button>
        <Button x:Name = "getUserBtn" Click = "getUserButton_Click" Grid.Row = "6" Grid.Column = "0">Get All</Button>
    </Grid>
</Page>