Refresh PhotoEditor C# sample to modern Windows App SDK conventions

Samples/PhotoEditor/README.md

@@ -32,6 +32,8 @@ A mini-app for viewing and editing image files, demonstrating XAML layout, data
 ### PhotoEditor C# Sample Application
 ![Photo Editor csharp sample showing the image collection page, and editing controls](images/CS_Picture1.png)
 
+> **Note**. The C# (`cs-winui`) sample has been refreshed to modern Windows App SDK conventions: it targets Windows App SDK 1.8, uses a Mica backdrop with a `TitleBar`, the `App.MainWindow`/`DispatcherQueue` window lifecycle, and nullable reference types, with the legacy UWP `ApiInformation`/`ConnectedAnimationService.GetForCurrentView` and contract-based conditional XAML removed. It loads its bundled sample photos from the app's install location (`Assets\Samples`).
+
 ## Features
 
 Photo Editor demonstrates:
@@ -41,8 +43,7 @@ Photo Editor demonstrates:
 * XAML styling and UI customization, including [connected animations](https://docs.microsoft.com/windows/uwp/design/motion/connected-animation).
 * Image effects from [**Windows.UI.Composition**](https://docs.microsoft.com/uwp/api/windows.ui.composition).
 * Loading images from the **Pictures** library using data virtualization to increase performance when there are numerous files.
-* The [**Microsoft.Graphics.Win2D**](https://microsoft.github.io/Win2D/WinUI3/html/Introduction.htm) NuGet package (an easy-to-use Windows Runtime API for immediate-mode 2D graphics rendering).
-For WinUI).
+* The [**Microsoft.Graphics.Win2D**](https://microsoft.github.io/Win2D/WinUI3/html/Introduction.htm) NuGet package (an easy-to-use Windows Runtime API for immediate-mode 2D graphics rendering for WinUI).
 
 ### C++/WinRT-specific features
 

Samples/PhotoEditor/cs-winui/.gitignore

@@ -0,0 +1,54 @@
+## .NET / Visual Studio
+[Bb]in/
+[Oo]bj/
+[Dd]ebug/
+[Rr]elease/
+.vs/
+*.user
+*.suo
+*.userosscache
+*.sln.docstates
+artifacts/
+
+# Build logs
+[Ll]og/
+[Ll]ogs/
+*.log
+*.binlog
+
+# Test results
+[Tt]est[Rr]esult*/
+*.trx
+*.coverage
+*.coveragexml
+
+# NuGet
+*.nupkg
+*.snupkg
+*.nuget.props
+*.nuget.targets
+project.lock.json
+
+# MSIX packaging output
+AppPackages/
+BundleArtifacts/
+*.msix
+*.msixupload
+*.appx
+*.appxbundle
+*.appxupload
+
+# Publish output
+publish/
+*.pubxml
+PublishScripts/
+
+# Code analysis and tooling
+_ReSharper*/
+*.DotSettings.user
+*.dotCover
+.idea/
+
+# Generated files
+Generated\ Files/
+*_wpftmp.csproj

Samples/PhotoEditor/cs-winui/App.xaml

@@ -1,4 +1,4 @@
-<!-- Copyright (c) Microsoft Corporation.
+<!-- Copyright (c) Microsoft Corporation.
  Licensed under the MIT License. -->
 
 <Application
@@ -10,12 +10,11 @@
         <ResourceDictionary>
             <ResourceDictionary.MergedDictionaries>
                 <XamlControlsResources xmlns="using:Microsoft.UI.Xaml.Controls" />
-                <!-- Other merged dictionaries here -->
             </ResourceDictionary.MergedDictionaries>
-            <!-- Other app resources here -->
-            <SolidColorBrush x:Key="RatingControlSelectedForeground" Color="White"/>
 
-            <!--  Window width adaptive breakpoints.  -->
+            <SolidColorBrush x:Key="RatingControlSelectedForeground" Color="White" />
+
+            <!-- Window width adaptive breakpoints. -->
             <x:Double x:Key="MinWindowBreakpoint">0</x:Double>
             <x:Double x:Key="MediumWindowBreakpoint">641</x:Double>
             <x:Double x:Key="LargeWindowBreakpoint">1008</x:Double>

Samples/PhotoEditor/cs-winui/App.xaml.cs

@@ -1,23 +1,47 @@
-// Copyright (c) Microsoft Corporation.
+// Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
-using Microsoft.UI.Xaml;
 using System;
+using Microsoft.UI.Dispatching;
+using Microsoft.UI.Xaml;
 
-// To learn more about WinUI, the WinUI project structure,
-// and more about our project templates, see: http://aka.ms/winui-project-info.
+namespace PhotoEditor;
 
-namespace PhotoEditor
+/// <summary>
+/// Provides application-specific behavior to supplement the default Application class.
+/// </summary>
+public partial class App : Application
 {
-    public partial class App : Application
+    /// <summary>
+    /// Gets the application's main window. WinUI 3 desktop has no <c>Window.Current</c>,
+    /// so the sample tracks the main window here (migration: Window.Current -> App.MainWindow).
+    /// </summary>
+    public static MainWindow MainWindow { get; private set; } = null!;
+
+    /// <summary>
+    /// Gets the DispatcherQueue for the UI thread. Replaces UWP's CoreDispatcher.
+    /// </summary>
+    public static DispatcherQueue MainDispatcherQueue { get; private set; } = null!;
+
+    /// <summary>
+    /// Gets the HWND of the main window, used to associate pickers with the window
+    /// (migration: pickers must be initialized with the owning window handle).
+    /// </summary>
+    public static IntPtr WindowHandle { get; private set; }
+
+    public App()
     {
-        protected override void OnLaunched(Microsoft.UI.Xaml.LaunchActivatedEventArgs args)
-        {
-            Window = new MainWindow();
-            Window.Activate();
-            WindowHandle = WinRT.Interop.WindowNative.GetWindowHandle(Window);
-        }
-        public static MainWindow Window { get; private set; }
-        public static IntPtr WindowHandle { get; private set; }
+        InitializeComponent();
+    }
+
+    protected override void OnLaunched(LaunchActivatedEventArgs args)
+    {
+        MainWindow = new MainWindow();
+        MainDispatcherQueue = MainWindow.DispatcherQueue;
+        WindowHandle = WinRT.Interop.WindowNative.GetWindowHandle(MainWindow);
+
+        // Navigate only after MainWindow is assigned: pages read App.MainWindow in OnNavigatedTo.
+        MainWindow.NavigateToMainPage();
+        MainWindow.Activate();
     }
-}
+}

Samples/PhotoEditor/cs-winui/DetailPage.xaml

@@ -1,15 +1,13 @@
-<!-- Copyright (c) Microsoft Corporation.
+<!-- Copyright (c) Microsoft Corporation.
  Licensed under the MIT License. -->
 
 <Page x:Class="PhotoEditor.DetailPage"
       xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
       xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
       xmlns:local="using:PhotoEditor"
-      xmlns:muxc="using:Microsoft.UI.Xaml.Controls"
       xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
       xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
-      mc:Ignorable="d"
-      RequestedTheme="Dark">
+      mc:Ignorable="d">
 
     <Page.Resources>
         <Flyout x:Key="zoomFlyout">
@@ -37,11 +35,7 @@
             </StackPanel>
         </Flyout>
 
-        <ControlTemplate TargetType="Slider" x:Key="FancySliderControlTemplate"
-                         xmlns:contract6Present="http://schemas.microsoft.com/winfx/2006/xaml/presentation?IsApiContractPresent(Windows.Foundation.UniversalApiContract,6)"
-                         xmlns:contract6NotPresent="http://schemas.microsoft.com/winfx/2006/xaml/presentation?IsApiContractNotPresent(Windows.Foundation.UniversalApiContract,6)"
-                         xmlns:contract7Present="http://schemas.microsoft.com/winfx/2006/xaml/presentation?IsApiContractPresent(Windows.Foundation.UniversalApiContract,7)"
-                         xmlns:contract7NotPresent="http://schemas.microsoft.com/winfx/2006/xaml/presentation?IsApiContractNotPresent(Windows.Foundation.UniversalApiContract,7)">
+        <ControlTemplate TargetType="Slider" x:Key="FancySliderControlTemplate">
             <Grid Margin="{TemplateBinding Padding}">
                 <Grid.Resources>
                     <Style TargetType="Thumb" x:Key="SliderThumbStyle">
@@ -239,16 +233,8 @@
 
                                     Height="{ThemeResource SliderTrackThemeHeight}"
                                     Grid.Row="1"
-                                    Grid.ColumnSpan="3"
-                                    contract7Present:RadiusX="{Binding CornerRadius, RelativeSource={RelativeSource TemplatedParent}, Converter={StaticResource TopLeftCornerRadiusDoubleValueConverter}}"
-                                    contract7Present:RadiusY="{Binding CornerRadius, RelativeSource={RelativeSource TemplatedParent}, Converter={StaticResource BottomRightCornerRadiusDoubleValueConverter}}"
-                                    contract7NotPresent:RadiusX="{Binding Source={ThemeResource ControlCornerRadius}, Converter={StaticResource TopLeftCornerRadiusDoubleValueConverter}}"
-                                    contract7NotPresent:RadiusY="{Binding Source={ThemeResource ControlCornerRadius}, Converter={StaticResource BottomRightCornerRadiusDoubleValueConverter}}" />
-                        <Rectangle x:Name="HorizontalDecreaseRect" Fill="{TemplateBinding Foreground}" Grid.Row="1"
-                                    contract7Present:RadiusX="{Binding CornerRadius, RelativeSource={RelativeSource TemplatedParent}, Converter={StaticResource TopLeftCornerRadiusDoubleValueConverter}}"
-                                    contract7Present:RadiusY="{Binding CornerRadius, RelativeSource={RelativeSource TemplatedParent}, Converter={StaticResource BottomRightCornerRadiusDoubleValueConverter}}"
-                                    contract7NotPresent:RadiusX="{Binding Source={ThemeResource ControlCornerRadius}, Converter={StaticResource TopLeftCornerRadiusDoubleValueConverter}}"
-                                    contract7NotPresent:RadiusY="{Binding Source={ThemeResource ControlCornerRadius}, Converter={StaticResource BottomRightCornerRadiusDoubleValueConverter}}" />
+                                    Grid.ColumnSpan="3" />
+                        <Rectangle x:Name="HorizontalDecreaseRect" Fill="{TemplateBinding Foreground}" Grid.Row="1" />
                         <TickBar x:Name="TopTickBar"
                                     Visibility="Collapsed"
                                     Fill="{ThemeResource SliderTickBarFill}"
@@ -299,19 +285,11 @@
                                     Fill="{TemplateBinding Background}"
                                     Width="{ThemeResource SliderTrackThemeHeight}"
                                     Grid.Column="1"
-                                    Grid.RowSpan="3"
-                                    contract7Present:RadiusX="{Binding CornerRadius, RelativeSource={RelativeSource TemplatedParent}, Converter={StaticResource TopLeftCornerRadiusDoubleValueConverter}}"
-                                    contract7Present:RadiusY="{Binding CornerRadius, RelativeSource={RelativeSource TemplatedParent}, Converter={StaticResource BottomRightCornerRadiusDoubleValueConverter}}"
-                                    contract7NotPresent:RadiusX="{Binding Source={ThemeResource ControlCornerRadius}, Converter={StaticResource TopLeftCornerRadiusDoubleValueConverter}}"
-                                    contract7NotPresent:RadiusY="{Binding Source={ThemeResource ControlCornerRadius}, Converter={StaticResource BottomRightCornerRadiusDoubleValueConverter}}" />
+                                    Grid.RowSpan="3" />
                         <Rectangle x:Name="VerticalDecreaseRect"
                                     Fill="{TemplateBinding Foreground}"
                                     Grid.Column="1"
-                                    Grid.Row="2"
-                                    contract7Present:RadiusX="{Binding CornerRadius, RelativeSource={RelativeSource TemplatedParent}, Converter={StaticResource TopLeftCornerRadiusDoubleValueConverter}}"
-                                    contract7Present:RadiusY="{Binding CornerRadius, RelativeSource={RelativeSource TemplatedParent}, Converter={StaticResource BottomRightCornerRadiusDoubleValueConverter}}"
-                                    contract7NotPresent:RadiusX="{Binding Source={ThemeResource ControlCornerRadius}, Converter={StaticResource TopLeftCornerRadiusDoubleValueConverter}}"
-                                    contract7NotPresent:RadiusY="{Binding Source={ThemeResource ControlCornerRadius}, Converter={StaticResource BottomRightCornerRadiusDoubleValueConverter}}" />
+                                    Grid.Row="2" />
                         <TickBar x:Name="LeftTickBar"
                                     Visibility="Collapsed"
                                     Fill="{ThemeResource SliderTickBarFill}"
@@ -350,7 +328,7 @@
 
     </Page.Resources>
 
-    <RelativePanel Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
+    <RelativePanel>
         <StackPanel x:Name="TitlePanel" Orientation="Horizontal">
             <AppBarButton x:Name="BackButton" Click="BackButton_Click" Margin="0, 0, 12, 0">
                 <SymbolIcon Symbol="Back"/>
@@ -364,7 +342,7 @@
                        Visibility="{x:Bind item.NeedsSaved, Mode=OneWay}" />
         </StackPanel>
         <CommandBar x:Name="MainCommandBar"
-                    Background="{ThemeResource ApplicationPageBackgroundThemeBrush}"
+                    Background="Transparent"
                     RelativePanel.AlignRightWithPanel="True"
                     RelativePanel.AlignTopWithPanel="True"
                     OverflowButtonVisibility="Collapsed"
@@ -466,12 +444,11 @@
                                  Text="{x:Bind item.ImageTitle, Mode=TwoWay}"
                                  Padding="12"
                                  Grid.ColumnSpan="2" />
-                        <muxc:RatingControl Value="{x:Bind item.ImageRating, Mode=TwoWay}"
-                                                Padding="12"
-                                                Grid.Row="1"
-                                                Grid.ColumnSpan="2"
-                                                Margin="0,0,0,16">
-                        </muxc:RatingControl>
+                        <RatingControl Value="{x:Bind item.ImageRating, Mode=TwoWay}"
+                                       Padding="12"
+                                       Grid.Row="1"
+                                       Grid.ColumnSpan="2"
+                                       Margin="0,0,0,16" />
 
 
                         <Slider Header="Exposure"