Why can't I filter my data?

[kyuranger]

I am a new being of DynamicData, I want to filter out the data containing letter 1, 2, 3 in WPF.

<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"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="auto"></RowDefinition>
            <RowDefinition Height="*"></RowDefinition>
        </Grid.RowDefinitions>
        <Grid VerticalAlignment="Top">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="auto"></ColumnDefinition>
                <ColumnDefinition Width="auto"></ColumnDefinition>
                <ColumnDefinition Width="auto"></ColumnDefinition>
            </Grid.ColumnDefinitions>
            <Button Click="Button_Click">1</Button>
            <Button Grid.Column="1" Click="Button_Click_1">2</Button>
            <Button Grid.Column="2" Click="Button_Click_2">3</Button>
        </Grid>
        <StackPanel Grid.Row="1">
            <ListBox x:Name="LB">

            </ListBox>
        </StackPanel>
    </Grid>
</Window>

using DynamicData.Binding;
using DynamicData;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace WpfApp1
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
            for (int i = 0; i <= 100; i++)
            {
                SourceList.Add(i.ToString());
            }
            SourceList.Connect().Bind(this.BindableList).Subscribe();
            LB.ItemsSource = BindableList;
        }
        private readonly SourceList<string> SourceList = new SourceList<string>();
        public IObservableCollection<string> BindableList { get; } = new ObservableCollectionExtended<string>();

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            SourceList.Connect().Filter(_ => _.Contains("1")).Bind(this.BindableList).Subscribe();
        }

        private void Button_Click_1(object sender, RoutedEventArgs e)
        {
            SourceList.Connect().Filter(_ => _.Contains("2")).Bind(this.BindableList).Subscribe();
        }

        private void Button_Click_2(object sender, RoutedEventArgs e)
        {
            SourceList.Connect().Filter(_ => _.Contains("3")).Bind(this.BindableList).Subscribe();
        }
    }
}

It seems it only sorts it but does not filter it. The data I don't need is still in the ListBox.

What's wrong with my code?

[bombizombi]

You connected to your source multiple times, and they all Bind to the same ObservableCollection. So, if you pressed all 3 buttons, your ListBox contains 3 filtered lists and also the original unfiltered list all bunched together.

You could use the Filter operator right from the start. It even accepts an IObservable of filter, so you can just push a new filter down its pipe, like this:

public partial class MainWindow : Window
 {
     public MainWindow()
     {
         InitializeComponent();
         for (int i = 0; i <= 100; i++)
         {
             SourceList.Add(i.ToString());
         }
         SourceList
             .Connect()
             .Filter(_filter)
             .Bind(this.BindableList)
             .Subscribe();
         LB.ItemsSource = BindableList;
     }
     private readonly SourceList<string> SourceList = new SourceList<string>();
     public IObservableCollection<string> BindableList { get; } = new ObservableCollectionExtended<string>();
     private BehaviorSubject<Func<string, bool>> _filter = new(x => true);

     private void Button_Click(object sender, RoutedEventArgs e)
     {
         _filter.OnNext(_ => _.Contains("1"));
     }

     private void Button_Click_1(object sender, RoutedEventArgs e)
     {
         _filter.OnNext(_ => _.Contains("2"));
     }

     private void Button_Click_2(object sender, RoutedEventArgs e)
     {
         _filter.OnNext(_ => _.Contains("3"));
     }
 }

[kyuranger]

Thank you so much.