Implement RefreshViewHandler on Windows

src/Controls/samples/Controls.Sample/Pages/Controls/RefreshViewPage.xaml

@@ -28,22 +28,18 @@
         <viewmodels:RefreshViewModel />
     </views:BasePage.BindingContext>
     <views:BasePage.Content>
-        <!--
-        https://github.com/dotnet/maui/issues/2022
-        <VerticalStackLayout
-            Margin="12">
-            <Label 
-                Text="Pull the items down to refresh the ScrollView."
-                Style="{StaticResource Headline}" />
-            <Label 
-                Text="{Binding Items.Count, StringFormat='Number of items: {0}'}" />-->
-
         <Grid>
             <Grid.RowDefinitions>
                 <RowDefinition Height="Auto"></RowDefinition>
                 <RowDefinition Height="*"></RowDefinition>
             </Grid.RowDefinitions>
             <VerticalStackLayout Grid.Row="0">
+                <VerticalStackLayout Margin="12">
+                    <Label 
+                        Text="Pull the items down to refresh the ScrollView."
+                        Style="{StaticResource Headline}" />
+                    <Label Text="{Binding Items.Count, StringFormat='Number of items: {0}'}" />
+                </VerticalStackLayout>
                 <HorizontalStackLayout>
                     <Button FontSize="10" Text="Toggle Refresh Color" Clicked="OnToggleRefreshColorClicked"></Button>
                     <Button FontSize="10" Text="Toggle Background Color" Clicked="OnToggleRefreshBackgroundColorClicked"></Button>
@@ -52,36 +48,28 @@
                     <Button FontSize="10" Text="Toggle Refresh" Clicked="OnTriggerRefreshClicked"></Button>
                     <Button FontSize="10" Text="Toggle Is Enabled" Clicked="OnToggleEnabledClicked"></Button>
                 </HorizontalStackLayout>
-                <HorizontalStackLayout>
+                <VerticalStackLayout>
                     <Label FontSize="10" Text="{Binding RefreshText}"></Label>
                     <Label FontSize="10" Text="{Binding EnabledText}"></Label>
-                </HorizontalStackLayout>
+                </VerticalStackLayout>
             </VerticalStackLayout>
-            <RefreshView  Grid.Row="1"
-                x:Name="refreshView"
-                IsRefreshing="{Binding IsRefreshing, Mode=TwoWay}"
-                IsEnabled="{Binding IsEnabled, Mode=TwoWay}"
-                RefreshColor="Teal"
-                Command="{Binding RefreshCommand}">
+            <RefreshView  
+                    Grid.Row="1"
+                    x:Name="refreshView"
+                    IsRefreshing="{Binding IsRefreshing, Mode=TwoWay}"
+                    IsEnabled="{Binding IsEnabled, Mode=TwoWay}"
+                    RefreshColor="Teal"
+                    Command="{Binding RefreshCommand}">
                 <ScrollView>
-                    <StackLayout 
-                        BindableLayout.ItemsSource="{Binding Items}"
-                        BindableLayout.ItemTemplate="{StaticResource ColorItemTemplate}">
-                    </StackLayout>
-                </ScrollView>
-                <!--
-                https://github.com/dotnet/maui/issues/2023
-                <FlexLayout 
+                    <FlexLayout
                         Direction="Row"
                         Wrap="Wrap"
                         AlignItems="Center"
                         AlignContent="Center"
                         BindableLayout.ItemsSource="{Binding Items}"
-                        BindableLayout.ItemTemplate="{StaticResource ColorItemTemplate}" />-->
-
+                        BindableLayout.ItemTemplate="{StaticResource ColorItemTemplate}" />
+                </ScrollView>
             </RefreshView>
         </Grid>
-
-        <!--</VerticalStackLayout>-->
     </views:BasePage.Content>
 </views:BasePage>

src/Controls/samples/Controls.Sample/ViewModels/RefreshViewModel.cs

@@ -57,7 +57,7 @@ void AddItems()
 			{
 				Items.Add(new RefreshItem
 				{
-					Color = Color.FromRgb(_random.Next(0, 255), _random.Next(0, 255), _random.Next(0, 255)),
+					Color = Color.FromRgb(_random.NextDouble(), _random.NextDouble(), _random.NextDouble()),
 					Name = $"Item {_itemNumber++}"
 				});
 			}

src/Controls/src/Core/Hosting/AppHostBuilderExtensions.cs

@@ -51,6 +51,7 @@ public static IMauiHandlersCollection AddMauiControlsHandlers(this IMauiHandlers
 			handlersCollection.AddHandler<ImageButton, ImageButtonHandler>();
 			handlersCollection.AddHandler<IndicatorView, IndicatorViewHandler>();
 			handlersCollection.AddHandler<RadioButton, RadioButtonHandler>();
+			handlersCollection.AddHandler<RefreshView, RefreshViewHandler>();
 			handlersCollection.AddHandler<SwipeItem, SwipeItemMenuItemHandler>();
 			handlersCollection.AddHandler<SwipeView, SwipeViewHandler>();
 
@@ -60,7 +61,6 @@ public static IMauiHandlersCollection AddMauiControlsHandlers(this IMauiHandlers
 			handlersCollection.AddHandler<MenuBarItem, MenuBarItemHandler>();
 
 #if ANDROID || IOS
-			handlersCollection.AddHandler<RefreshView, RefreshViewHandler>();
 			handlersCollection.AddHandler<SwipeItemView, SwipeItemViewHandler>();
 #endif
 #if WINDOWS || ANDROID

src/Core/src/Handlers/RefreshView/RefreshViewHandler.Windows.cs

@@ -1,35 +1,127 @@
-using System;
-using System.Collections.Generic;
-using System.Text;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Maui.Dispatching;
+using Microsoft.Maui.Graphics;
 using Microsoft.UI.Xaml.Controls;
+using Windows.Foundation;
+using WBrush = Microsoft.UI.Xaml.Media.Brush;
 
 namespace Microsoft.Maui.Handlers
 {
 	public partial class RefreshViewHandler : ViewHandler<IRefreshView, RefreshContainer>
 	{
+		bool _isLoaded;
+		Deferral? _refreshCompletionDeferral;
+
 		protected override RefreshContainer CreatePlatformView()
 		{
-			return new RefreshContainer();
+			return new RefreshContainer
+			{
+				PullDirection = RefreshPullDirection.TopToBottom
+			};
 		}
 
-		[MissingMapper]
-		public static void MapIsRefreshing(IRefreshViewHandler handler, IRefreshView refreshView)
+		protected override void ConnectHandler(RefreshContainer nativeView)
 		{
+			nativeView.Loaded += OnLoaded;
+			nativeView.RefreshRequested += OnRefresh;
+
+			base.ConnectHandler(nativeView);
 		}
 
-		[MissingMapper]
-		public static void MapContent(IRefreshViewHandler handler, IRefreshView refreshView)
+		protected override void DisconnectHandler(RefreshContainer nativeView)
 		{
+			nativeView.Loaded -= OnLoaded;
+			nativeView.RefreshRequested -= OnRefresh;
+
+			CompleteRefresh();
+
+			base.DisconnectHandler(nativeView);
 		}
 
-		[MissingMapper]
+		public static void MapIsRefreshing(IRefreshViewHandler handler, IRefreshView refreshView)
+			=> (handler as RefreshViewHandler)?.UpdateIsRefreshing();
+
+		public static void MapContent(IRefreshViewHandler handler, IRefreshView refreshView)
+			=> UpdateContent(handler);
+
 		public static void MapRefreshColor(IRefreshViewHandler handler, IRefreshView refreshView)
+			=> UpdateRefreshColor(handler);
+
+		public static void MapRefreshViewBackground(IRefreshViewHandler handler, IView view)
+			=> UpdateBackground(handler);
+
+		void UpdateIsRefreshing()
 		{
+			if (!_isLoaded)
+				return;
+
+			if (!VirtualView?.IsRefreshing ?? false)
+				CompleteRefresh();
+			else if (_refreshCompletionDeferral == null)
+				PlatformView?.RequestRefresh();
 		}
 
-		[MissingMapper]
-		public static void MapRefreshViewBackground(IRefreshViewHandler handler, IView view)
+		static void UpdateContent(IRefreshViewHandler handler)
+		{
+			handler.PlatformView.Content =
+				handler.VirtualView.Content.ToPlatform(handler.MauiContext!);
+		}
+
+		static void UpdateRefreshColor(IRefreshViewHandler handler)
+		{
+			if (handler.VirtualView == null || handler.PlatformView?.Visualizer == null)
+				return;
+
+			handler.PlatformView.Visualizer.Foreground = handler.VirtualView.RefreshColor != null	
+				? handler.VirtualView.RefreshColor.ToPlatform()	
+				: (WBrush)UI.Xaml.Application.Current.Resources["DefaultTextForegroundThemeBrush"];
+		}
+
+		static void UpdateBackground(IRefreshViewHandler handler)
+		{
+			if (handler.PlatformView?.Visualizer == null)
+				return;
+
+			if (handler.VirtualView.Background != null)
+				handler.PlatformView.Visualizer.Background = handler.VirtualView.Background.ToPlatform();
+		}
+
+		// Telling the refresh to start before the control has been sized
+		// causes no refresh circle to show up
+		void OnLoaded(object sender, object args)
+		{
+			var refreshControl = sender as RefreshContainer;
+
+			if (refreshControl == null || MauiContext == null)
+				return;
+
+			refreshControl.Loaded -= OnLoaded;
+			MauiContext.Services
+				.GetRequiredService<IDispatcher>()
+				.Dispatch(() =>
+				{
+					_isLoaded = true;
+					UpdateIsRefreshing();
+				});
+		}
+
+		void OnRefresh(object sender, RefreshRequestedEventArgs args)
+		{
+			CompleteRefresh();
+			_refreshCompletionDeferral = args.GetDeferral();
+
+			if (VirtualView != null)
+				VirtualView.IsRefreshing = true;
+		}
+
+		void CompleteRefresh()
 		{
+			if (_refreshCompletionDeferral != null)
+			{
+				_refreshCompletionDeferral.Complete();
+				_refreshCompletionDeferral.Dispose();
+				_refreshCompletionDeferral = null;
+			}
 		}
 	}
 }

src/Core/src/Handlers/RefreshView/RefreshViewHandler.iOS.cs

@@ -17,12 +17,14 @@ protected override MauiRefreshView CreatePlatformView()
 		protected override void ConnectHandler(MauiRefreshView platformView)
 		{
 			platformView.RefreshControl.ValueChanged += OnRefresh;
+
 			base.ConnectHandler(platformView);
 		}
 
 		protected override void DisconnectHandler(MauiRefreshView platformView)
 		{
 			platformView.RefreshControl.ValueChanged -= OnRefresh;
+
 			base.DisconnectHandler(platformView);
 		}
 
@@ -61,6 +63,5 @@ static void UpdateRefreshColor(IRefreshViewHandler handler)
 			if (color != null)
 				handler.PlatformView.RefreshControl.TintColor = color;
 		}
-
 	}
 }