How to display List property In nested object c# MAUI

I’m working on an app in MAUI C#. Here is my code:

View :

<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="testbinding.MainPage"
             xmlns:local="clr-namespace:testbinding.ViewModel"
             x:DataType="local:TestViewModel">

    <ScrollView>
        <VerticalStackLayout>
            <CollectionView x:Name="Buttons" ItemsSource="{Binding TestModel.Toto}" EmptyView="pas de data" IsGrouped="True">
                <CollectionView.ItemTemplate >
                    <DataTemplate >
                        <VerticalStackLayout Spacing="300000" >
                            <Label Text="{Binding Plop}"></Label>
                        </VerticalStackLayout>
                    </DataTemplate>
                </CollectionView.ItemTemplate>
            </CollectionView>
        </VerticalStackLayout>
    </ScrollView>

</ContentPage>

The viewModel :

namespace testbinding.ViewModel
{
    public class TestViewModel : INotifyPropertyChanged
    {
        public TestModel TestModel { get; } = new TestModel();


        public TestViewModel()
        {
            TestModel = //call api that return the right object
            
        }

        public event PropertyChangedEventHandler PropertyChanged;

        void OnPropertyChanged(string propertyName) =>
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
  
    }
}

the model :

namespace testbinding.Model
{
    public class TestModel : INotifyPropertyChanged
    {
       private string id;
       private string name;
       private List<Toto> toto;
        public string Id 
        { 
          get { return id; }
          set { id = value; OnPropertyChanged(nameof(Id)); }
        }

        public string Name
        {
            get { return name; }
            set { name = value; OnPropertyChanged(nameof(Name)); }
        }

        public List<Toto> Toto
        {
            get { return toto; }
            set { toto =  value; OnPropertyChanged(nameof(Toto)); }
        }

        public event PropertyChangedEventHandler PropertyChanged;

        void OnPropertyChanged(string name) =>
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
    
    }
}

and the model in list:

namespace testbinding.Model
{
    public class Toto : INotifyPropertyChanged
    {
        private int id { get; set; }
        private string  plop { get; set; }
        public int Id 
        { get { return id; }
          set { id = value; OnPropertyChanged(nameof(Id)); }
        }
        public string  Plop
        {
            get { return plop; }
            set { plop = value; OnPropertyChanged(nameof(Plop)); }
        }

        public event PropertyChangedEventHandler PropertyChanged;

        void OnPropertyChanged(string name) =>
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
    }
}

I’m new with MVVM and I want to display the property Plop in a label in collectionView. I have this Error: Binding: Property "Plop" not found on "testbinding.ViewModel.TestViewModel". testbinding C:\sources\testbinding\MainPage.xaml.

I don’t understand the problem my property is in the model Toto and the call API return the right object with the datas.

>Solution :

you need to add an xmlns for your models

xmlns:model="clr-namespace:testbinding.Model"

then add this to your DataTemplate

<DataTemplate x:DataType="model:Toto" >