Fix: Fixed issue where the preview pane didn't update when switching panes (#12647)

Author: hishitetsu

src/Files.App/Views/LayoutModes/BaseLayout.cs

@@ -188,7 +188,7 @@ public string JumpString
 			}
 		}
 
-		protected bool LockPreviewPaneContent { get; set; }
+		public bool LockPreviewPaneContent { get; set; }
 
 		private List<ListedItem>? selectedItems = new List<ListedItem>();
 		public List<ListedItem>? SelectedItems

src/Files.App/Views/LayoutModes/IBaseLayout.cs

@@ -13,22 +13,27 @@ public interface IBaseLayout : IDisposable
 
 		bool IsMiddleClickToScrollEnabled { get; set; }
 
-		public List<ListedItem>? SelectedItems { get; }
+		/// <summary>
+		/// If true, the preview pane is not updated when the selected item is changed.
+		/// </summary>
+		bool LockPreviewPaneContent { get; set; }
 
-		public ListedItem? SelectedItem { get; }
+		List<ListedItem>? SelectedItems { get; }
+
+		ListedItem? SelectedItem { get; }
 
 		ItemManipulationModel ItemManipulationModel { get; }
 
 		PreviewPaneViewModel PreviewPaneViewModel { get; }
 
-		public SelectedItemsPropertiesViewModel SelectedItemsPropertiesViewModel { get; }
+		SelectedItemsPropertiesViewModel SelectedItemsPropertiesViewModel { get; }
 
-		public DirectoryPropertiesViewModel DirectoryPropertiesViewModel { get; }
+		DirectoryPropertiesViewModel DirectoryPropertiesViewModel { get; }
 
-		public BaseLayoutCommandsViewModel? CommandsViewModel { get; }
+		BaseLayoutCommandsViewModel? CommandsViewModel { get; }
 
-		public CommandBarFlyout ItemContextMenuFlyout { get; set; }
+		CommandBarFlyout ItemContextMenuFlyout { get; set; }
 
-		public CommandBarFlyout BaseContextMenuFlyout { get; set; }
+		CommandBarFlyout BaseContextMenuFlyout { get; set; }
 	}
 }

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

@@ -324,15 +324,33 @@ private void Pane_Loaded(object sender, RoutedEventArgs e)
 			((UIElement)sender).GotFocus += Pane_GotFocus;
 		}
 
-		private void Pane_GotFocus(object sender, RoutedEventArgs e)
+		private async void Pane_GotFocus(object sender, RoutedEventArgs e)
 		{
 			var isLeftPane = sender == PaneLeft;
 			if (isLeftPane && (PaneRight?.SlimContentPage?.IsItemSelected ?? false))
+			{
+				PaneRight.SlimContentPage.LockPreviewPaneContent = true;
 				PaneRight.SlimContentPage.ItemManipulationModel.ClearSelection();
+				PaneRight.SlimContentPage.LockPreviewPaneContent = false;
+			}
 			else if (!isLeftPane && (PaneLeft?.SlimContentPage?.IsItemSelected ?? false))
+			{
+				PaneLeft.SlimContentPage.LockPreviewPaneContent = true;
 				PaneLeft.SlimContentPage.ItemManipulationModel.ClearSelection();
+				PaneLeft.SlimContentPage.LockPreviewPaneContent = false;
+			}
 
-			ActivePane = isLeftPane ? PaneLeft : PaneRight;
+			var activePane = isLeftPane ? PaneLeft : PaneRight;
+			if (ActivePane != activePane)
+			{
+				ActivePane = activePane;
+
+				if (ActivePane?.SlimContentPage is IBaseLayout page && !page.IsItemSelected)
+				{
+					page.PreviewPaneViewModel.IsItemSelected = false;
+					await page.PreviewPaneViewModel.UpdateSelectedItemPreview();
+				}
+			}
 		}
 
 		public void Dispose()