Feature: Display banner when recent items are turned off from File Explorer

src/Files.App/Filesystem/RecentItems.cs

@@ -1,6 +1,7 @@
 using Files.App.Helpers;
 using Files.App.Shell;
 using Files.Shared.Extensions;
+using Microsoft.Win32;
 using System;
 using System.Collections.Generic;
 using System.Collections.Specialized;
@@ -204,6 +205,47 @@ public Task<bool> UnpinFromRecentFiles(RecentItem item)
 			}));
 		}
 
+		public bool CheckIsRecentFilesEnabled()
+		{
+			using var subkey = Registry.CurrentUser.OpenSubKey(@"SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer");
+			using var advSubkey = Registry.CurrentUser.OpenSubKey(@"SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced");
+			using var userPolicySubkey = Registry.CurrentUser.OpenSubKey(@"SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer");
+			using var sysPolicySubkey = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer");
+
+			if (subkey is not null)
+			{
+				// quick access: show recent files option
+				bool showRecentValue = Convert.ToBoolean(subkey.GetValue("ShowRecent", true)); // 1 by default
+				if (!showRecentValue)
+				{
+					return false;
+				}
+			}
+
+			if (advSubkey is not null)
+			{
+				// settings: personalization > start > show recently opened items
+				bool startTrackDocsValue = Convert.ToBoolean(advSubkey.GetValue("Start_TrackDocs", true)); // 1 by default
+				if (!startTrackDocsValue)
+				{
+					return false;
+				}
+			}
+
+			// for users in group policies
+			var policySubkey = userPolicySubkey ?? sysPolicySubkey;
+			if (policySubkey is not null)
+			{
+				bool noRecentDocsHistoryValue = Convert.ToBoolean(policySubkey.GetValue("NoRecentDocsHistory", false)); // 0 by default
+				if (noRecentDocsHistoryValue)
+				{
+					return false;
+				}
+			}
+
+			return true;
+		}
+
 		/// <summary>
 		/// Returns whether two RecentItem enumerables have the same order.
 		/// This function depends on `RecentItem` implementing IEquatable.
@@ -212,6 +254,7 @@ private bool RecentItemsOrderEquals(IEnumerable<RecentItem> oldOrder, IEnumerabl
 		{
 			return oldOrder != null && newOrder != null && oldOrder.SequenceEqual(newOrder);
 		}
+
 		public void Dispose()
 		{
 			RecentItemsManager.Default.RecentItemsChanged -= OnRecentItemsChanged;

src/Files.App/Strings/en-US/Resources.resw

@@ -2935,4 +2935,7 @@
   <data name="SortBy" xml:space="preserve">
     <value>Sort by</value>
   </data>
+  <data name="RecentFilesDisabledOnWindowsWarning" xml:space="preserve">
+    <value>Recently used files is currently disabled in Windows File Explorer.</value>
+  </data>
 </root>

src/Files.App/UserControls/Widgets/RecentFilesWidget.xaml

@@ -5,7 +5,7 @@
 	xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
 	xmlns:fs="using:Files.App.Filesystem"
 	xmlns:helpers="using:Files.App.Helpers"
-	xmlns:local="using:Files.App.UserControls.Widgets"
+	xmlns:muxc="using:Microsoft.UI.Xaml.Controls"
 	xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
 	Background="{ThemeResource SolidBackgroundFillColorBaseBrush}"
 	mc:Ignorable="d">
@@ -15,14 +15,21 @@
 		MinHeight="200"
 		Orientation="Vertical"
 		Spacing="4">
+		<muxc:InfoBar
+			IsClosable="False"
+			IsIconVisible="True"
+			IsOpen="True"
+			Message="{helpers:ResourceString Name=RecentFilesDisabledOnWindowsWarning}"
+			Severity="Warning"
+			Visibility="{x:Bind IsRecentFilesDisabledInWindows, Mode=OneWay}" />
 		<TextBlock
 			x:Name="RecentItemDescription"
 			HorizontalAlignment="Stretch"
 			FontSize="14"
 			Text="{helpers:ResourceString Name=RecentItemDescription/Text}"
 			TextAlignment="Center"
 			TextWrapping="WrapWholeWords"
-			Visibility="{x:Bind Empty.Visibility, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
+			Visibility="{x:Bind EmptyRecentsTextVisibility, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
 		<ListView
 			x:Name="RecentsView"
 			HorizontalAlignment="Stretch"
@@ -129,4 +136,4 @@
 			</ListView.ItemTemplate>
 		</ListView>
 	</StackPanel>
-</UserControl>
+</UserControl>

src/Files.App/UserControls/Widgets/RecentFilesWidget.xaml.cs

@@ -18,7 +18,7 @@
 
 namespace Files.App.UserControls.Widgets
 {
-	public sealed partial class RecentFilesWidget : UserControl, IWidgetItemModel
+	public sealed partial class RecentFilesWidget : UserControl, IWidgetItemModel, INotifyPropertyChanged
 	{
 		private IUserSettingsService UserSettingsService { get; } = Ioc.Default.GetRequiredService<IUserSettingsService>();
 
@@ -30,14 +30,14 @@ public sealed partial class RecentFilesWidget : UserControl, IWidgetItemModel
 
 		public event RecentFileInvokedEventHandler RecentFileInvoked;
 
+		public event PropertyChangedEventHandler PropertyChanged;
+
 		private ObservableCollection<RecentItem> recentItemsCollection = new ObservableCollection<RecentItem>();
 
 		private SemaphoreSlim refreshRecentsSemaphore;
 
 		private CancellationTokenSource refreshRecentsCTS;
 
-		private EmptyRecentsText Empty { get; set; } = new EmptyRecentsText();
-
 		public string WidgetName => nameof(RecentFilesWidget);
 
 		public string AutomationProperties => "RecentFilesWidgetAutomationProperties/Name".GetLocalizedResource();
@@ -46,6 +46,34 @@ public sealed partial class RecentFilesWidget : UserControl, IWidgetItemModel
 
 		public bool IsWidgetSettingEnabled => UserSettingsService.AppearanceSettingsService.ShowRecentFilesWidget;
 
+		private Visibility emptyRecentsTextVisibility = Visibility.Collapsed;
+		public Visibility EmptyRecentsTextVisibility
+		{
+			get => emptyRecentsTextVisibility;
+			internal set
+			{
+				if (emptyRecentsTextVisibility != value)
+				{
+					emptyRecentsTextVisibility = value;
+					NotifyPropertyChanged(nameof(EmptyRecentsTextVisibility));
+				}
+			}
+		}
+
+		private bool isRecentFilesDisabledInWindows = false;
+		public bool IsRecentFilesDisabledInWindows
+		{
+			get => isRecentFilesDisabledInWindows;
+			internal set
+			{
+				if (isRecentFilesDisabledInWindows != value)
+				{
+					isRecentFilesDisabledInWindows = value;
+					NotifyPropertyChanged(nameof(IsRecentFilesDisabledInWindows));
+				}
+			}
+		}
+
 		public RecentFilesWidget()
 		{
 			InitializeComponent();
@@ -54,11 +82,17 @@ public RecentFilesWidget()
 			refreshRecentsCTS = new CancellationTokenSource();
 
 			// recent files could have changed while widget wasn't loaded
-			_ = App.RecentItemsManager.UpdateRecentFilesAsync();
+			_ = RefreshWidget();
 
 			App.RecentItemsManager.RecentFilesChanged += Manager_RecentFilesChanged;
 		}
 
+		public async Task RefreshWidget()
+		{
+			IsRecentFilesDisabledInWindows = App.RecentItemsManager.CheckIsRecentFilesEnabled() is false;
+			await App.RecentItemsManager.UpdateRecentFilesAsync();
+		}
+
 		private async void Manager_RecentFilesChanged(object sender, NotifyCollectionChangedEventArgs e)
 		{
 			await DispatcherQueue.EnqueueAsync(async () =>
@@ -100,7 +134,7 @@ private async Task UpdateRecentsList(NotifyCollectionChangedEventArgs e)
 				refreshRecentsCTS.Cancel();
 				refreshRecentsCTS = new CancellationTokenSource();
 
-				Empty.Visibility = Visibility.Collapsed;
+				EmptyRecentsTextVisibility = Visibility.Collapsed;
 
 				switch (e.Action)
 				{
@@ -131,9 +165,9 @@ private async Task UpdateRecentsList(NotifyCollectionChangedEventArgs e)
 				}
 
 				// update chevron if there aren't any items
-				if (recentItemsCollection.Count == 0)
+				if (recentItemsCollection.Count == 0 && !IsRecentFilesDisabledInWindows)
 				{
-					Empty.Visibility = Visibility.Visible;
+					EmptyRecentsTextVisibility = Visibility.Visible;
 				}
 			}
 			catch (Exception ex)
@@ -202,7 +236,7 @@ private async void ClearRecentItems_Click(object sender, RoutedEventArgs e)
 
 				if (success)
 				{
-					Empty.Visibility = Visibility.Visible;
+					EmptyRecentsTextVisibility = Visibility.Visible;
 				}
 			}
 			finally
@@ -211,43 +245,14 @@ private async void ClearRecentItems_Click(object sender, RoutedEventArgs e)
 			}
 		}
 
-		public Task RefreshWidget()
+		private void NotifyPropertyChanged([CallerMemberName] string propertyName = "")
 		{
-			// if files changed, event is fired to update widget
-			return App.RecentItemsManager.UpdateRecentFilesAsync();
+			PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
 		}
 
 		public void Dispose()
 		{
 			App.RecentItemsManager.RecentFilesChanged -= Manager_RecentFilesChanged;
 		}
 	}
-
-	public class EmptyRecentsText : INotifyPropertyChanged
-	{
-		private Visibility visibility;
-
-		public Visibility Visibility
-		{
-			get
-			{
-				return visibility;
-			}
-			set
-			{
-				if (value != visibility)
-				{
-					visibility = value;
-					NotifyPropertyChanged(nameof(Visibility));
-				}
-			}
-		}
-
-		public event PropertyChangedEventHandler PropertyChanged;
-
-		private void NotifyPropertyChanged([CallerMemberName] string propertyName = "")
-		{
-			PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
-		}
-	}
 }