Add back propoerty load cancellation

Author: hez2010

Files/ViewModels/ItemViewModel.cs

@@ -46,6 +46,7 @@ public class ItemViewModel : ObservableObject, IDisposable
     {
         private readonly SemaphoreSlim enumFolderSemaphore;
         private readonly ConcurrentQueue<(uint Action, string FileName)> operationQueue;
+        private readonly ConcurrentDictionary<string, bool> itemLoadQueue;
         private readonly AsyncManualResetEvent operationEvent, loadPropsEvent;
         private IntPtr hWatchDir;
         private IAsyncAction aWatcherAction;
@@ -344,6 +345,7 @@ public ItemViewModel(FolderSettingsViewModel folderSettingsViewModel)
             filesAndFolders = new List<ListedItem>();
             FilesAndFolders = new BulkConcurrentObservableCollection<ListedItem>();
             operationQueue = new ConcurrentQueue<(uint Action, string FileName)>();
+            itemLoadQueue = new ConcurrentDictionary<string, bool>();
             addFilesCTS = new CancellationTokenSource();
             semaphoreCTS = new CancellationTokenSource();
             loadPropsCTS = new CancellationTokenSource();
@@ -452,6 +454,11 @@ public void CancelExtendedPropertiesLoading()
             loadPropsCTS = new CancellationTokenSource();
         }
 
+        public void CancelExtendedPropertiesLoadingForItem(ListedItem item)
+        {
+            itemLoadQueue.TryUpdate(item.ItemPath, true, false);
+        }
+
         public async Task ApplySingleFileChangeAsync(ListedItem item)
         {
             var newIndex = filesAndFolders.IndexOf(item);
@@ -900,13 +907,19 @@ public async Task LoadExtendedItemProperties(ListedItem item, uint thumbnailSize
             }
 
             item.ItemPropertiesInitialized = true;
+            itemLoadQueue[item.ItemPath] = false;
 
             try
             {
                 await Task.Run(async () =>
                 {
                     await loadPropsEvent.WaitAsync(loadPropsCTS.Token);
 
+                    if (itemLoadQueue.TryGetValue(item.ItemPath, out var canceled) && canceled)
+                    {
+                        return;
+                    }
+
                     var wasSyncStatusLoaded = false;
                     ImageSource groupImage = null;
                     bool loadGroupHeaderInfo = false;
@@ -1032,6 +1045,10 @@ await FilesystemTasks.Wrap(() => CoreApplication.MainView.DispatcherQueue.Enqueu
             {
                 // ignored
             }
+            finally
+            {
+                itemLoadQueue.TryRemove(item.ItemPath, out _);
+            }
         }
 
         private async Task<ImageSource> GetItemTypeGroupIcon(ListedItem item, BaseStorageFile matchingStorageItem = null)

Files/Views/LayoutModes/ColumnViewBase.xaml.cs

@@ -564,6 +564,10 @@ private void FileList_ContainerContentChanging(ListViewBase sender, ContainerCon
             {
                 UninitializeDrag(args.ItemContainer);
                 args.ItemContainer.PointerPressed -= FileListListItem_PointerPressed;
+                if (args.Item is ListedItem item)
+                {
+                    ParentShellPageInstance.FilesystemViewModel.CancelExtendedPropertiesLoadingForItem(item);
+                }
             }
         }
 

Files/Views/LayoutModes/ColumnViewBrowser.xaml.cs

@@ -740,6 +740,10 @@ private void FileList_ContainerContentChanging(ListViewBase sender, ContainerCon
             {
                 UninitializeDrag(args.ItemContainer);
                 args.ItemContainer.PointerPressed -= FileListListItem_PointerPressed;
+                if (args.Item is ListedItem item)
+                {
+                    ParentShellPageInstance.FilesystemViewModel.CancelExtendedPropertiesLoadingForItem(item);
+                }
             }
         }
 

Files/Views/LayoutModes/DetailsLayoutBrowser.xaml.cs

@@ -698,6 +698,10 @@ private void FileList_ContainerContentChanging(ListViewBase sender, ContainerCon
             {
                 UninitializeDrag(args.ItemContainer);
                 args.ItemContainer.PointerPressed -= FileListGridItem_PointerPressed;
+                if (args.Item is ListedItem item)
+                {
+                    ParentShellPageInstance.FilesystemViewModel.CancelExtendedPropertiesLoadingForItem(item);
+                }
             }
         }
 

Files/Views/LayoutModes/GridViewBrowser.xaml.cs

@@ -587,6 +587,10 @@ private void FileList_ContainerContentChanging(ListViewBase sender, ContainerCon
             {
                 UninitializeDrag(args.ItemContainer);
                 args.ItemContainer.PointerPressed -= FileListGridItem_PointerPressed;
+                if (args.Item is ListedItem item)
+                {
+                    ParentShellPageInstance.FilesystemViewModel.CancelExtendedPropertiesLoadingForItem(item);
+                }
             }
         }
     }