POC

Author: yaira2

src/Files.App/Views/Layouts/BaseGroupableLayoutPage.cs

@@ -95,7 +95,7 @@ protected override void UnhookEvents()
 			ItemManipulationModel.RefreshItemsThumbnailInvoked -= ItemManipulationModel_RefreshItemsThumbnail;
 		}
 
-		protected override void Page_CharacterReceived(UIElement sender, CharacterReceivedRoutedEventArgs args)
+		protected override void Page_PreviewKeyDown(object sender, KeyRoutedEventArgs e)
 		{
 			if (ParentShellPageInstance is null ||
 				ParentShellPageInstance.CurrentPageType != this.GetType() ||
@@ -112,7 +112,7 @@ focusedElement is PasswordBox ||
 				DependencyObjectHelpers.FindParent<ContentDialog>(focusedElement) is not null)
 				return;
 
-			base.Page_CharacterReceived(sender, args);
+			base.Page_PreviewKeyDown(sender, e);
 		}
 
 		// Virtual methods

src/Files.App/Views/Layouts/BaseLayoutPage.cs

@@ -6,6 +6,7 @@
 using Files.App.Helpers.ContextFlyouts;
 using Files.App.UserControls.Menus;
 using Files.App.ViewModels.Layouts;
+using Microsoft.UI.Input;
 using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Controls;
 using Microsoft.UI.Xaml.Controls.Primitives;
@@ -23,6 +24,7 @@
 using Windows.Foundation.Collections;
 using Windows.Storage;
 using Windows.System;
+using Windows.UI.Core;
 using static Files.App.Helpers.PathNormalization;
 using DispatcherQueueTimer = Microsoft.UI.Dispatching.DispatcherQueueTimer;
 using SortDirection = Files.App.Data.Enums.SortDirection;
@@ -401,7 +403,7 @@ protected override async void OnNavigatedTo(NavigationEventArgs e)
 			base.OnNavigatedTo(e);
 
 			// Add item jumping handler
-			CharacterReceived += Page_CharacterReceived;
+			PreviewKeyDown += Page_PreviewKeyDown; ;
 
 			navigationArguments = (NavigationArguments)e.Parameter;
 			ParentShellPageInstance = navigationArguments.AssociatedTabInstance;
@@ -565,7 +567,7 @@ protected override void OnNavigatingFrom(NavigatingCancelEventArgs e)
 			base.OnNavigatingFrom(e);
 
 			// Remove item jumping handler
-			CharacterReceived -= Page_CharacterReceived;
+			PreviewKeyDown -= Page_PreviewKeyDown;
 			FolderSettings!.LayoutModeChangeRequested -= BaseFolderSettings_LayoutModeChangeRequested;
 			FolderSettings.GroupOptionPreferenceUpdated -= FolderSettings_GroupOptionPreferenceUpdated;
 			FolderSettings.GroupDirectionPreferenceUpdated -= FolderSettings_GroupDirectionPreferenceUpdated;
@@ -996,12 +998,39 @@ private void RemoveOverflow(CommandBarFlyout contextMenuFlyout)
 				overflowSeparator.Visibility = Visibility.Collapsed;
 		}
 
-		protected virtual void Page_CharacterReceived(UIElement sender, CharacterReceivedRoutedEventArgs args)
+		protected virtual void Page_PreviewKeyDown(object sender, KeyRoutedEventArgs e)
 		{
-			if (ParentShellPageInstance!.IsCurrentInstance)
+			var key = e.Key;
+			var filter = ParentShellPageInstance?.ShellViewModel.FilesAndFoldersFilter;
+
+			if (ParentShellPageInstance?.IsCurrentInstance != true)
+				return;
+
+			// OemMinus usually maps to virtual key code 189
+			bool isOemMinus = (int)key == 189;
+			bool isShiftDown = InputKeyboardSource.GetKeyStateForCurrentThread(VirtualKey.Shift).HasFlag(CoreVirtualKeyStates.Down);
+
+			char? keyChar = key switch
+			{
+				>= VirtualKey.A and <= VirtualKey.Z => (char)('A' + (key - VirtualKey.A)),
+				>= VirtualKey.Number0 and <= VirtualKey.Number9 => (char)('0' + (key - VirtualKey.Number0)),
+				_ => isOemMinus ? (isShiftDown ? '_' : '-') : null
+			};
+
+			if (keyChar.HasValue &&
+				!Path.GetInvalidFileNameChars().Contains(char.ToLowerInvariant(keyChar.Value)))
+			{
+				string ch = keyChar.Value.ToString().ToLowerInvariant();
+				ParentShellPageInstance.ShellViewModel.FilesAndFoldersFilter += ch;
+				JumpString += ch;
+			}
+			else if (key == VirtualKey.Space && !string.IsNullOrEmpty(filter))
+			{
+				ParentShellPageInstance.ShellViewModel.FilesAndFoldersFilter += " ";
+			}
+			else if (key == VirtualKey.Back && !string.IsNullOrEmpty(filter))
 			{
-				char letter = args.Character;
-				JumpString += letter.ToString().ToLowerInvariant();
+				ParentShellPageInstance.ShellViewModel.FilesAndFoldersFilter = filter[..^1];
 			}
 		}
 

src/Files.App/Views/MainPage.xaml.cs

@@ -216,6 +216,10 @@ private async Task OnPreviewKeyDownAsync(KeyRoutedEventArgs e)
 					if (source?.FindAscendantOrSelf<TextBox>() is not null)
 						break;
 
+					// Prevent the back key from executing a command if the filter header is not empty
+					if (e.Key is VirtualKey.Back && !string.IsNullOrEmpty(SidebarAdaptiveViewModel.PaneHolder?.ActivePaneOrColumn!.ShellViewModel.FilesAndFoldersFilter))
+						break;
+
 					// Execute command for hotkey
 					var command = Commands[hotKey];