Enable cache mode for LayoutModes (#3464)

Author: gave92

Files/BaseLayout.cs

@@ -290,6 +290,7 @@ private void FolderSettings_LayoutModeChangeRequested(object sender, EventArgs e
 
                 if (layoutType != ParentShellPageInstance.CurrentPageType)
                 {
+                    FolderSettings.IsLayoutModeChanging = true;
                     ParentShellPageInstance.ContentFrame.Navigate(layoutType, new NavigationArguments()
                     {
                         NavPathParam = navigationArguments.NavPathParam,

Files/ViewModels/ItemViewModel.cs

@@ -2275,10 +2275,10 @@ private void NotifyPropertyChanged([CallerMemberName] string propertyName = "")
 
         public void Dispose()
         {
+            CancelLoadAndClearFiles();
             addFilesCTS?.Dispose();
             semaphoreCTS?.Dispose();
             loadPropsCTS?.Dispose();
-            CloseWatcher();
         }
 
         /// <summary>

Files/Views/LayoutModes/GenericFileBrowser.xaml

@@ -17,7 +17,7 @@
     xmlns:muxc="using:Microsoft.UI.Xaml.Controls"
     xmlns:usercontrols="using:Files.UserControls"
     Background="{ThemeResource ApplicationPageBackgroundThemeBrush}"
-    NavigationCacheMode="Disabled"
+    NavigationCacheMode="Enabled"
     PointerWheelChanged="BaseLayout_PointerWheelChanged"
     mc:Ignorable="d">
 

Files/Views/LayoutModes/GenericFileBrowser.xaml.cs

@@ -112,11 +112,14 @@ private void SelectionRectangle_SelectionEnded(object sender, EventArgs e)
         protected override void OnNavigatedTo(NavigationEventArgs eventArgs)
         {
             base.OnNavigatedTo(eventArgs);
-            AllView.ItemsSource = ParentShellPageInstance.FilesystemViewModel.FilesAndFolders;
             ParentShellPageInstance.FilesystemViewModel.PropertyChanged += ViewModel_PropertyChanged;
             AllView.LoadingRow += AllView_LoadingRow;
             AllView.UnloadingRow += AllView_UnloadingRow;
             AppSettings.ThemeModeChanged += AppSettings_ThemeModeChanged;
+            if (AllView.ItemsSource == null)
+            {
+                AllView.ItemsSource = ParentShellPageInstance.FilesystemViewModel.FilesAndFolders;
+            }
             ViewModel_PropertyChanged(null, new PropertyChangedEventArgs("DirectorySortOption"));
             var parameters = (NavigationArguments)eventArgs.Parameter;
             if (parameters.IsLayoutSwitch)
@@ -154,8 +157,10 @@ protected override void OnNavigatingFrom(NavigatingCancelEventArgs e)
             AllView.LoadingRow -= AllView_LoadingRow;
             AllView.UnloadingRow -= AllView_UnloadingRow;
             AppSettings.ThemeModeChanged -= AppSettings_ThemeModeChanged;
-
-            AllView.ItemsSource = null;
+            if (e.SourcePageType != typeof(GenericFileBrowser))
+            {
+                AllView.ItemsSource = null;
+            }
         }
 
         private void AppSettings_ThemeModeChanged(object sender, EventArgs e)

Files/Views/LayoutModes/GridViewBrowser.xaml

@@ -15,7 +15,7 @@
     xmlns:muxc="using:Microsoft.UI.Xaml.Controls"
     x:Name="PageRoot"
     Background="{ThemeResource ApplicationPageBackgroundThemeBrush}"
-    NavigationCacheMode="Disabled"
+    NavigationCacheMode="Enabled"
     PointerPressed="GridViewBrowserViewer_PointerPressed"
     PointerWheelChanged="BaseLayout_PointerWheelChanged"
     mc:Ignorable="d">

Files/Views/LayoutModes/GridViewBrowser.xaml.cs

@@ -35,11 +35,14 @@ public GridViewBrowser()
         protected override void OnNavigatedTo(NavigationEventArgs eventArgs)
         {
             base.OnNavigatedTo(eventArgs);
-            FileList.ItemsSource = ParentShellPageInstance.FilesystemViewModel.FilesAndFolders;
             currentIconSize = GetIconSize();
             FolderSettings.LayoutModeChangeRequested -= FolderSettings_LayoutModeChangeRequested;
             FolderSettings.LayoutModeChangeRequested += FolderSettings_LayoutModeChangeRequested;
             SetItemTemplate(); // Set ItemTemplate
+            if (FileList.ItemsSource == null)
+            {
+                FileList.ItemsSource = ParentShellPageInstance.FilesystemViewModel.FilesAndFolders;
+            }
             var parameters = (NavigationArguments)eventArgs.Parameter;
             if (parameters.IsLayoutSwitch)
             {
@@ -60,8 +63,10 @@ protected override void OnNavigatingFrom(NavigatingCancelEventArgs e)
             base.OnNavigatingFrom(e);
             FolderSettings.LayoutModeChangeRequested -= FolderSettings_LayoutModeChangeRequested;
             FolderSettings.GridViewSizeChangeRequested -= FolderSettings_GridViewSizeChangeRequested;
-
-            FileList.ItemsSource = null;
+            if (e.SourcePageType != typeof(GridViewBrowser))
+            {
+                FileList.ItemsSource = null;
+            }
         }
 
         private async void SelectionRectangle_SelectionEnded(object sender, EventArgs e)