From 727c4b9c7468f0a019152bd08d16a95984c0e5c4 Mon Sep 17 00:00:00 2001
From: Andrew KeepCoding <andrewkeepcoding@gmail.com>
Date: Sat, 22 Nov 2025 11:09:51 +0900
Subject: [PATCH] Add sample code

---
 WinUIDemoApp/Shell.xaml    |  26 +++++++
 WinUIDemoApp/Shell.xaml.cs | 137 +++++++++++++++++++++++++++++++++++++
 2 files changed, 163 insertions(+)

diff --git a/WinUIDemoApp/Shell.xaml b/WinUIDemoApp/Shell.xaml
index b134cb1..a05b7e5 100644
--- a/WinUIDemoApp/Shell.xaml
+++ b/WinUIDemoApp/Shell.xaml
@@ -9,4 +9,30 @@
     Background="{ThemeResource ApplicationPageBackgroundThemeBrush}"
     mc:Ignorable="d">
 
+    <Grid Margin="8" ColumnDefinitions="*,*,*">
+        <StackPanel Grid.Column="0" Spacing="4">
+            <Button Command="{x:Bind ViewModel.AddItemCommand}" Content="Add item" />
+            <Button
+                Command="{x:Bind ViewModel.RemoveItemCommand}"
+                CommandParameter="{x:Bind ItemsListView.SelectedIndex, Mode=OneWay}"
+                Content="Remove item" />
+            <Button
+                Command="{x:Bind ViewModel.ReplaceItemCommand}"
+                CommandParameter="{x:Bind ItemsListView.SelectedIndex, Mode=OneWay}"
+                Content="Replace item" />
+            <Button Command="{x:Bind ViewModel.MoveItemCommand}" Content="Move item" />
+            <Button Command="{x:Bind ViewModel.ResetItemsCommand}" Content="Reset items" />
+        </StackPanel>
+        <ListView
+            x:Name="ItemsListView"
+            Grid.Column="1"
+            ItemsSource="{x:Bind ViewModel.Items}"
+            SelectedItem="{x:Bind ViewModel.SelectedItem, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
+        <ListView
+            x:Name="LogsListView"
+            Grid.Column="2"
+            ItemsSource="{x:Bind ViewModel.Logs}"
+            SelectedItem="{x:Bind ViewModel.SelectedLog, Mode=OneWay}" />
+    </Grid>
+
 </Page>
diff --git a/WinUIDemoApp/Shell.xaml.cs b/WinUIDemoApp/Shell.xaml.cs
index 9945b61..16c4e19 100644
--- a/WinUIDemoApp/Shell.xaml.cs
+++ b/WinUIDemoApp/Shell.xaml.cs
@@ -1,10 +1,124 @@
 using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
+using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Controls;
+using System;
+using System.Collections.ObjectModel;
+using System.Collections.Specialized;
 
 namespace WinUIDemoApp;
 
 public partial class ShellViewModel : ObservableObject
 {
+    public ShellViewModel()
+    {
+        Items.CollectionChanged += Items_CollectionChanged;
+    }
+
+    public ObservableCollection<string> Items { get; } = [];
+
+    public ObservableCollection<string> Logs { get; } = [];
+
+    [ObservableProperty]
+    public partial string? SelectedItem { get; set; }
+
+
+    [ObservableProperty]
+    public partial string? SelectedLog { get; set; }
+
+
+    [RelayCommand]
+    private void AddItem() => Items.Add($"Item {Items.Count}");
+
+    [RelayCommand]
+    private void RemoveItem(int index)
+    {
+        try
+        {
+            Items.RemoveAt(index);
+        }
+        catch (Exception exception)
+        {
+            Logs.Add($"Error removing item at index {index}: {exception.Message}");
+        }
+    }
+
+    [RelayCommand]
+    private void ReplaceItem(int index)
+    {
+        try
+        {
+            var item = Items[index];
+            Items[index] = item + " (Updated)";
+        }
+        catch (Exception exception)
+        {
+            Logs.Add($"Error replacing item at index {index}: {exception.Message}");
+        }
+    }
+
+    [RelayCommand]
+    private void MoveItem()
+    {
+        try
+        {
+            if (SelectedItem is null)
+            {
+                Logs.Add("No item selected to move.");
+                return;
+            }
+
+            int selectedItemIndex = Items.IndexOf(SelectedItem);
+            Items.Move(selectedItemIndex, (selectedItemIndex + 1) % Items.Count);
+        }
+        catch (Exception exception)
+        {
+            Logs.Add($"Error moving item: {exception.Message}");
+        }
+    }
+
+    [RelayCommand]
+    private void ResetItems()
+    {
+        Items.Clear();
+    }
+
+    private void Items_CollectionChanged(object? sender, NotifyCollectionChangedEventArgs e)
+    {
+        string logEntry = $"Time: {DateTime.Now}" + Environment.NewLine;
+        logEntry += $"Action: {e.Action}" + Environment.NewLine;
+
+        logEntry += $"Old Starting Index: {e.OldStartingIndex}" + Environment.NewLine;
+
+        if (e.OldItems is not null)
+        {
+            foreach (var oldItem in e.OldItems)
+            {
+                logEntry += $"Old Item: {oldItem}" + Environment.NewLine;
+            }
+        }
+        else
+        {
+            logEntry += "Old Items: None" + Environment.NewLine;
+        }
+
+        logEntry += $"New Starting Index: {e.NewStartingIndex}" + Environment.NewLine;
+
+        if (e.NewItems is not null)
+        {
+            foreach (var newItem in e.NewItems)
+            {
+                logEntry += $"New Item: {newItem}" + Environment.NewLine;
+            }
+        }
+        else
+        {
+            logEntry += "New Items: None" + Environment.NewLine;
+        }
+
+        Logs.Add(logEntry);
+        SelectedLog = logEntry;
+    }
 }
 
 public sealed partial class Shell : Page
@@ -12,7 +126,30 @@ public sealed partial class Shell : Page
     public Shell()
     {
         InitializeComponent();
+        LogsListView.Loaded += LogsListView_Loaded;
+        LogsListView.Unloaded += LogsListView_Unloaded;
     }
 
     public ShellViewModel ViewModel { get; } = new();
+
+    private void LogsListView_Loaded(object sender, Microsoft.UI.Xaml.RoutedEventArgs e)
+    {
+        if (sender is not ListView listView || listView.ItemsPanelRoot is null)
+            return;
+
+        listView.ItemsPanelRoot.SizeChanged += ItemsPanelRoot_SizeChanged;
+    }
+
+    private void LogsListView_Unloaded(object sender, RoutedEventArgs e)
+    {
+        if (sender is not ListView listView || listView.ItemsPanelRoot is null)
+            return;
+
+        listView.ItemsPanelRoot?.SizeChanged -= ItemsPanelRoot_SizeChanged;
+    }
+
+    private void ItemsPanelRoot_SizeChanged(object sender, Microsoft.UI.Xaml.SizeChangedEventArgs e)
+    {
+        LogsListView.ScrollIntoView(ViewModel.SelectedLog);
+    }
 }