Moved asynchronous image loading to Tile class

MapControl/Avalonia/Tile.Avalonia.cs

@@ -1,33 +1,47 @@
 using Avalonia;
 using Avalonia.Animation;
+using Avalonia.Media;
 using Avalonia.Styling;
+using Avalonia.Threading;
 using System;
+using System.Threading.Tasks;
 
 namespace MapControl
 {
     public partial class Tile
     {
-        private void FadeIn()
+        public async Task LoadImageAsync(Func<Task<IImage>> loadImageFunc)
         {
-            var fadeInAnimation = new Animation
+            var image = await loadImageFunc().ConfigureAwait(false);
-            {
-                Duration = MapBase.ImageFadeDuration,
-                Children =
-                {
-                    new KeyFrame
-                    {
-                        KeyTime = TimeSpan.Zero,
-                        Setters = { new Setter(Visual.OpacityProperty, 0d) }
-                    },
-                    new KeyFrame
-                    {
-                        KeyTime = MapBase.ImageFadeDuration,
-                        Setters = { new Setter(Visual.OpacityProperty, 1d) }
-                    }
-                }
-            };
 
-            _ = fadeInAnimation.RunAsync(Image);
+            await Dispatcher.UIThread.InvokeAsync(
+                () =>
+                {
+                    Image.Source = image;
+
+                    if (image != null && MapBase.ImageFadeDuration > TimeSpan.Zero)
+                    {
+                        var fadeInAnimation = new Animation
+                        {
+                            Duration = MapBase.ImageFadeDuration,
+                            Children =
+                            {
+                                new KeyFrame
+                                {
+                                    KeyTime = TimeSpan.Zero,
+                                    Setters = { new Setter(Visual.OpacityProperty, 0d) }
+                                },
+                                new KeyFrame
+                                {
+                                    KeyTime = MapBase.ImageFadeDuration,
+                                    Setters = { new Setter(Visual.OpacityProperty, 1d) }
+                                }
+                            }
+                        };
+
+                        _ = fadeInAnimation.RunAsync(Image);
+                    }
+                });
         }
     }
 }

MapControl/Avalonia/TileImageLoader.Avalonia.cs

@@ -1,18 +0,0 @@
-using Avalonia.Media;
-using Avalonia.Threading;
-using System;
-using System.Threading;
-using System.Threading.Tasks;
-
-namespace MapControl
-{
-    public partial class TileImageLoader
-    {
-        private static async Task LoadTileImage(Tile tile, Func<Task<IImage>> loadImageFunc)
-        {
-            var image = await loadImageFunc().ConfigureAwait(false);
-
-            await Dispatcher.UIThread.InvokeAsync(() => tile.SetImageSource(image));
-        }
-    }
-}

MapControl/Shared/Tile.cs

@@ -1,5 +1,4 @@
-using System;
+#if WPF
-#if WPF
 using System.Windows.Controls;
 using System.Windows.Media;
 #elif UWP
@@ -25,25 +24,12 @@ namespace MapControl
             Column = ((x % columnCount) + columnCount) % columnCount;
         }
 
+        public Image Image { get; } = new Image { Stretch = Stretch.Fill };
         public int ZoomLevel { get; }
         public int X { get; }
         public int Y { get; }
         public int Column { get; }
         public int Row => Y;
-
-        public Image Image { get; } = new Image { Stretch = Stretch.Fill };
-
         public bool IsPending { get; set; } = true;
-
-        public void SetImageSource(ImageSource image)
-        {
-            IsPending = false;
-            Image.Source = image;
-
-            if (image != null && MapBase.ImageFadeDuration > TimeSpan.Zero)
-            {
-                FadeIn();
-            }
-        }
     }
 }

MapControl/Shared/TileImageLoader.cs

@@ -7,13 +7,6 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Threading.Tasks;
-#if WPF
-using System.Windows.Media;
-#elif UWP
-using Windows.UI.Xaml.Media;
-#elif WINUI
-using Microsoft.UI.Xaml.Media;
-#endif
 
 namespace MapControl
 {
@@ -27,7 +20,7 @@ namespace MapControl
         void CancelLoadTiles();
     }
 
-    public partial class TileImageLoader : ITileImageLoader
+    public class TileImageLoader : ITileImageLoader
     {
         private static ILogger logger;
         private static ILogger Logger => logger ?? (logger = ImageLoader.LoggerFactory?.CreateLogger<TileImageLoader>());
@@ -161,9 +154,7 @@ namespace MapControl
 
             if (string.IsNullOrEmpty(cacheName))
             {
-                Task<ImageSource> LoadImage() => tileSource.LoadImageAsync(tile.Column, tile.Row, tile.ZoomLevel);
+                await tile.LoadImageAsync(() => tileSource.LoadImageAsync(tile.Column, tile.Row, tile.ZoomLevel)).ConfigureAwait(false);
-
-                await LoadTileImage(tile, LoadImage).ConfigureAwait(false);
             }
             else
             {
@@ -175,9 +166,7 @@ namespace MapControl
 
                     if (buffer?.Length > 0)
                     {
-                        Task<ImageSource> LoadImage() => tileSource.LoadImageAsync(buffer);
+                        await tile.LoadImageAsync(() => tileSource.LoadImageAsync(buffer)).ConfigureAwait(false);
-
-                        await LoadTileImage(tile, LoadImage).ConfigureAwait(false);
                     }
                 }
             }

MapControl/UWP/MapControl.UWP.csproj

@@ -282,7 +282,6 @@
       <Link>Tile.WinUI.cs</Link>
     </Compile>
     <Compile Include="Properties\AssemblyInfo.cs" />
-    <Compile Include="TileImageLoader.UWP.cs" />
     <EmbeddedResource Include="Properties\MapControl.UWP.rd.xml" />
   </ItemGroup>
   <ItemGroup>

MapControl/UWP/TileImageLoader.UWP.cs

@@ -1,36 +0,0 @@
-using System;
-using System.Threading;
-using System.Threading.Tasks;
-using Windows.UI.Core;
-using Windows.UI.Xaml.Media;
-
-namespace MapControl
-{
-    public partial class TileImageLoader
-    {
-        private static async Task LoadTileImage(Tile tile, Func<Task<ImageSource>> loadImageFunc)
-        {
-            var tcs = new TaskCompletionSource<object>();
-
-            async void LoadTileImage()
-            {
-                try
-                {
-                    tile.SetImageSource(await loadImageFunc());
-                    tcs.TrySetResult(null);
-                }
-                catch (Exception ex)
-                {
-                    tcs.TrySetException(ex);
-                }
-            }
-
-            if (!await tile.Image.Dispatcher.TryRunAsync(CoreDispatcherPriority.Low, LoadTileImage))
-            {
-                tcs.TrySetCanceled();
-            }
-
-            await tcs.Task;
-        }
-    }
-}

MapControl/WPF/Tile.WPF.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Threading.Tasks;
 using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Media;
@@ -9,6 +10,30 @@ namespace MapControl
 {
     public partial class Tile
     {
+        public async Task LoadImageAsync(Func<Task<ImageSource>> loadImageFunc)
+        {
+            var image = await loadImageFunc().ConfigureAwait(false);
+
+            await Image.Dispatcher.InvokeAsync(
+                () =>
+                {
+                    Image.Source = image;
+
+                    if (image != null && MapBase.ImageFadeDuration > TimeSpan.Zero)
+                    {
+                        if (image is BitmapSource bitmap && !bitmap.IsFrozen && bitmap.IsDownloading)
+                        {
+                            bitmap.DownloadCompleted += BitmapDownloadCompleted;
+                            bitmap.DownloadFailed += BitmapDownloadFailed;
+                        }
+                        else
+                        {
+                            BeginFadeInAnimation();
+                        }
+                    }
+                });
+        }
+
         private void BeginFadeInAnimation()
         {
             var fadeInAnimation = new DoubleAnimation
@@ -21,19 +46,6 @@ namespace MapControl
             Image.BeginAnimation(UIElement.OpacityProperty, fadeInAnimation);
         }
 
-        private void FadeIn()
-        {
-            if (Image.Source is BitmapSource bitmap && !bitmap.IsFrozen && bitmap.IsDownloading)
-            {
-                bitmap.DownloadCompleted += BitmapDownloadCompleted;
-                bitmap.DownloadFailed += BitmapDownloadFailed;
-            }
-            else
-            {
-                BeginFadeInAnimation();
-            }
-        }
-
         private void BitmapDownloadCompleted(object sender, EventArgs e)
         {
             var bitmap = (BitmapSource)sender;

MapControl/WPF/TileImageLoader.WPF.cs

@@ -1,17 +0,0 @@
-using System;
-using System.Threading;
-using System.Threading.Tasks;
-using System.Windows.Media;
-
-namespace MapControl
-{
-    public partial class TileImageLoader
-    {
-        private static async Task LoadTileImage(Tile tile, Func<Task<ImageSource>> loadImageFunc)
-        {
-            var image = await loadImageFunc().ConfigureAwait(false);
-
-            await tile.Image.Dispatcher.InvokeAsync(() => tile.SetImageSource(image));
-        }
-    }
-}

MapControl/WinUI/Tile.WinUI.cs

@@ -1,9 +1,15 @@
-#if UWP
+using System;
+using System.Threading.Tasks;
+#if UWP
+using Windows.UI.Core;
 using Windows.UI.Xaml;
+using Windows.UI.Xaml.Media;
 using Windows.UI.Xaml.Media.Animation;
 using Windows.UI.Xaml.Media.Imaging;
 #else
+using Microsoft.UI.Dispatching;
 using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Media;
 using Microsoft.UI.Xaml.Media.Animation;
 using Microsoft.UI.Xaml.Media.Imaging;
 #endif
@@ -12,6 +18,50 @@ namespace MapControl
 {
     public partial class Tile
     {
+        public async Task LoadImageAsync(Func<Task<ImageSource>> loadImageFunc)
+        {
+            var tcs = new TaskCompletionSource<object>();
+
+            async void LoadImage()
+            {
+                try
+                {
+                    var image = await loadImageFunc();
+
+                    Image.Source = image;
+
+                    if (image != null && MapBase.ImageFadeDuration > TimeSpan.Zero)
+                    {
+                        if (image is BitmapImage bitmap && bitmap.UriSource != null)
+                        {
+                            bitmap.ImageOpened += BitmapImageOpened;
+                            bitmap.ImageFailed += BitmapImageFailed;
+                        }
+                        else
+                        {
+                            BeginFadeInAnimation();
+                        }
+                    }
+
+                    tcs.TrySetResult(null);
+                }
+                catch (Exception ex)
+                {
+                    tcs.TrySetException(ex);
+                }
+            }
+#if UWP
+            if (!await Image.Dispatcher.TryRunAsync(CoreDispatcherPriority.Low, LoadImage))
+#else
+            if (!Image.DispatcherQueue.TryEnqueue(DispatcherQueuePriority.Low, LoadImage))
+#endif
+            {
+                tcs.TrySetCanceled();
+            }
+
+            await tcs.Task;
+        }
+
         private void BeginFadeInAnimation()
         {
             var fadeInAnimation = new DoubleAnimation
@@ -29,19 +79,6 @@ namespace MapControl
             storyboard.Begin();
         }
 
-        private void FadeIn()
-        {
-            if (Image.Source is BitmapImage bitmap && bitmap.UriSource != null)
-            {
-                bitmap.ImageOpened += BitmapImageOpened;
-                bitmap.ImageFailed += BitmapImageFailed;
-            }
-            else
-            {
-                BeginFadeInAnimation();
-            }
-        }
-
         private void BitmapImageOpened(object sender, RoutedEventArgs e)
         {
             var bitmap = (BitmapImage)sender;

MapControl/WinUI/TileImageLoader.WinUI.cs

@@ -1,36 +0,0 @@
-using Microsoft.UI.Dispatching;
-using Microsoft.UI.Xaml.Media;
-using System;
-using System.Threading;
-using System.Threading.Tasks;
-
-namespace MapControl
-{
-    public partial class TileImageLoader
-    {
-        private static Task LoadTileImage(Tile tile, Func<Task<ImageSource>> loadImageFunc)
-        {
-            var tcs = new TaskCompletionSource();
-
-            async void LoadTileImage()
-            {
-                try
-                {
-                    tile.SetImageSource(await loadImageFunc());
-                    tcs.TrySetResult();
-                }
-                catch (Exception ex)
-                {
-                    tcs.TrySetException(ex);
-                }
-            }
-
-            if (!tile.Image.DispatcherQueue.TryEnqueue(DispatcherQueuePriority.Low, LoadTileImage))
-            {
-                tcs.TrySetCanceled();
-            }
-
-            return tcs.Task;
-        }
-    }
-}