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C# can't binding to list view using observable collection

I have a problem when I try to bind a collection of type observable to listView. I am sure that the collection is updating correctly but nothing happening in the list view.

I am retrieving JSON objects and convert them to a collection of Observable.

public partial class MainWindow : Window
{
    public ObservableCollection<post> mproducts = new ObservableCollection<post>();

    public MainWindow()
    {

        InitializeComponent();
        DataContext = mproducts;
    }
    private static readonly HttpClient Client = new HttpClient();
    async void OnLoad(object sender, RoutedEventArgs e)
    {
        HttpResponseMessage response = await Client.GetAsync("https://jsonplaceholder.typicode.com/posts");
        response.EnsureSuccessStatusCode();
        string data = await response.Content.ReadAsStringAsync();

        mproducts = JsonConvert.DeserializeObject<ObservableCollection<post>>(data);
        MessageBox.Show(mproducts.Count.ToString());

    }
    public class post
    {
        public string UserId { get; set; }
        public string Id { get; set; }
        public string Title { get; set; }
        public string Body { get; set; }
    }

}

this is the XAML class:

<Window x:Class="WpfApp1.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"
        xmlns:local="clr-namespace:WpfApp1"
        mc:Ignorable="d"
        Loaded="OnLoad"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
    
        <ListView x:Name="products" Margin="400,0,0,0" Width="600" SelectionChanged="ListView_SelectionChanged" ItemsSource="{Binding mproducts}"; >
           
           
            <ListView.View>
                <GridView>
                    <GridViewColumn Width="160" Header="Description" DisplayMemberBinding="{Binding UserId}"/>
                    <GridViewColumn Width="160" Header="Date Filed" DisplayMemberBinding="{Binding Id}"/>
                    <GridViewColumn Width="160" Header="Filed By" DisplayMemberBinding="{Binding Title}"/>
                    <GridViewColumn Width="150" Header="Page" DisplayMemberBinding="{Binding Body}"/>
                    <GridViewColumn Width="Auto" Header="" />
                </GridView>
            </ListView.View>
        </ListView>
    </Grid>


</Window>

when the app loads it shows in the Message box number 100, which means the collection is updated.

The binding of the ListBox should look like this

ItemsSource="{Binding}"

because you are binding to the collection itself which is stored in the DataContext . Also in your code you should do DataContext = mproducts; in the OnLoad event after you assign the collection to mproducts like this:

mproducts = JsonConvert.DeserializeObject<ObservableCollection<post>>(data);
DataContext = mproducts;

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