Small fix for threading.

Microsoft.Toolkit.Uwp.SampleApp/Data/GitHub.cs

@@ -5,9 +5,9 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Net.Http;
 using System.Threading.Tasks;
 using Newtonsoft.Json;
-using Windows.Web.Http;
 
 namespace Microsoft.Toolkit.Uwp.SampleApp.Data
 {
@@ -27,11 +27,22 @@ namespace Microsoft.Toolkit.Uwp.SampleApp.Data
                 {
                     using (var client = new HttpClient())
                     {
-                        client.DefaultRequestHeaders.TryAppendWithoutValidation("User-Agent", "Mozilla/5.0 (Windows NT 10.0; WOW64; Trident/7.0; rv:11.0) like Gecko");
-
                         var uri = $"{_root}/repos/{_repoOwner}/{_repoName}/releases";
-                        var result = await client.GetStringAsync(new Uri(uri));
-                        _releases = JsonConvert.DeserializeObject<List<GitHubRelease>>(result).Take(5).ToList();
+
+                        var request = new HttpRequestMessage(HttpMethod.Get, uri);
+                        request.Headers.Add("User-Agent", "Mozilla/5.0 (Windows NT 10.0; WOW64; Trident/7.0; rv:11.0) like Gecko");
+
+                        using (request)
+                        {
+                            using (var response = await client.SendAsync(request))
+                            {
+                                if (response.IsSuccessStatusCode)
+                                {
+                                    var result = await response.Content.ReadAsStringAsync();
+                                    _releases = JsonConvert.DeserializeObject<List<GitHubRelease>>(result).Take(5).ToList();
+                                }
+                            }
+                        }
                     }
                 }
                 catch (Exception)

Microsoft.Toolkit.Uwp.SampleApp/Models/Sample.cs

@@ -569,20 +569,16 @@ namespace Microsoft.Toolkit.Uwp.SampleApp
                                         options = new PropertyOptions();
                                         var split = value.Split('.');
                                         var typeName = string.Join(".", split.Take(split.Length - 1));
-                                        Debug.WriteLine("AAA");
                                         var enumType = LookForTypeByName(typeName);
                                         options.DefaultValue = Enum.Parse(enumType, split.Last());
                                     }
                                     catch (Exception ex)
                                     {
-                                        Debug.WriteLine("BBB");
                                         Debug.WriteLine($"Unable to parse enum from {value}({ex.Message})");
                                         TrackingManager.TrackException(ex);
                                         continue;
                                     }
 
-                                    Debug.WriteLine("CCC");
-
                                     break;
 
                                 case PropertyKind.Bool:

Microsoft.Toolkit.Uwp.SampleApp/Models/Samples.cs

@@ -4,6 +4,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.IO;
 using System.Linq;
 using System.Threading;
@@ -63,7 +64,9 @@ namespace Microsoft.Toolkit.Uwp.SampleApp
             var fullFileName = Path.Combine(_installedLocationPath, "Microsoft.Toolkit.Uwp.SampleApp", fileName);
 
             var stream = new MemoryStream();
+            Debug.WriteLine($"LoadLocalFile{Thread.CurrentThread.ManagedThreadId}");
             await File.OpenRead(fullFileName).CopyToAsync(stream);
+            Debug.WriteLine($"LoadLocalFile{Thread.CurrentThread.ManagedThreadId} End");
             stream.Seek(0, SeekOrigin.Begin);
 
             return stream;

Microsoft.Toolkit.Uwp.SampleApp/Pages/About.xaml.cs

@@ -5,9 +5,11 @@
 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
+using System.Diagnostics;
 using System.IO;
 using System.Linq;
 using System.Runtime.CompilerServices;
+using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.Toolkit.Uwp.Helpers;
 using Microsoft.Toolkit.Uwp.UI.Animations;
@@ -107,7 +109,7 @@ namespace Microsoft.Toolkit.Uwp.SampleApp.Pages
 
             _compositor = ElementCompositionPreview.GetElementVisual(this).Compositor;
 
-            var t = Init();
+            _ = Init();
 
             Window.Current.CoreWindow.KeyDown += CoreWindow_KeyDown;
         }
@@ -129,34 +131,45 @@ namespace Microsoft.Toolkit.Uwp.SampleApp.Pages
 
         private async Task Init()
         {
+            Debug.WriteLine(Thread.CurrentThread.ManagedThreadId);
+
             var loadDataTask = UpdateSections();
             var recentSamplesTask = Samples.GetRecentSamples();
             var gitHubTask = Data.GitHub.GetPublishedReleases();
 
+            Debug.WriteLine(Thread.CurrentThread.ManagedThreadId);
+
             await Task.WhenAll(loadDataTask, recentSamplesTask, gitHubTask);
 
-            RecentSamples = recentSamplesTask.Result;
-            GitHubReleases = gitHubTask.Result;
+            Debug.WriteLine(Thread.CurrentThread.ManagedThreadId);
 
-            var counter = 1;
-            var delay = 70;
-
-            foreach (var child in InnerGrid.Children)
+            // Workaround WinUI3 threading issue
+            await DispatcherQueue.ExecuteOnUIThreadAsync(() =>
             {
-                if (child is ItemsControl itemsControl == false)
-                {
-                    Implicit.GetShowAnimations(child).Add(new OpacityAnimation()
-                    {
-                        From = 0,
-                        To = 1,
-                        Duration = TimeSpan.FromMilliseconds(300),
-                        Delay = TimeSpan.FromMilliseconds(counter++ * delay),
-                        SetInitialValueBeforeDelay = true
-                    });
-                }
-            }
+                RecentSamples = recentSamplesTask.Result;
 
-            Root.Visibility = Visibility.Visible;
+                GitHubReleases = gitHubTask.Result;
+
+                var counter = 1;
+                var delay = 70;
+
+                foreach (var child in InnerGrid.Children)
+                {
+                    if (child is ItemsControl itemsControl == false)
+                    {
+                        Implicit.GetShowAnimations(child).Add(new OpacityAnimation()
+                        {
+                            From = 0,
+                            To = 1,
+                            Duration = TimeSpan.FromMilliseconds(300),
+                            Delay = TimeSpan.FromMilliseconds(counter++ * delay),
+                            SetInitialValueBeforeDelay = true
+                        });
+                    }
+                }
+
+                Root.Visibility = Visibility.Visible;
+            });
         }
 
         private void RecentSample_Click(object sender, RoutedEventArgs e)

Windows Community Toolkit.sln

@@ -58,6 +58,7 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution
 		Directory.Build.props = Directory.Build.props
 		Directory.Build.targets = Directory.Build.targets
 		global.json = global.json
+		nuget.config = nuget.config
 	EndProjectSection
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Microsoft.Toolkit.Uwp.Notifications.JavaScript", "Microsoft.Toolkit.Uwp.Notifications.JavaScript\Microsoft.Toolkit.Uwp.Notifications.JavaScript.csproj", "{94F8D702-3A9D-4CFB-85C9-79FC5DBD8B22}"

nuget.config

@@ -11,5 +11,6 @@
     <add key="nuget.org" value="https://api.nuget.org/v3/index.json" protocolVersion="3" />
     <add key="WinUI.Dependencies@Local" value="https://microsoft.pkgs.visualstudio.com/_packaging/WinUI.Dependencies%40Local/nuget/v3/index.json" />
     <add key="CsWinRT" value="https://microsoft.pkgs.visualstudio.com/_packaging/CsWinRT/nuget/v3/index.json" />
-	</packageSources>
+    <add key="dotnet5@Local" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet5%40Local/nuget/v3/index.json" />
+  </packageSources>
 </configuration>