DYN-10516: Refresh Templates and Recent Files from disk dynamically

src/DynamoCoreWpf/Controls/StartPage.xaml.cs

@@ -1,5 +1,6 @@
 using Dynamo.Configuration;
 using Dynamo.Logging;
+using Dynamo.UI.Prompts;
 using Dynamo.Utilities;
 using Dynamo.ViewModels;
 using Dynamo.Wpf.Properties;
@@ -279,6 +280,17 @@ private void AddTemplateListItemFromPath(string filePath)
             this.TemplateFiles.Add(templateItem);
         }
 
+        internal void RefreshTemplateFiles()
+        {
+            TemplateFiles.Clear();
+            LoadTemplates();
+        }
+
+        internal void RefreshRecentFiles()
+        {
+            RefreshRecentFileList(DynamoViewModel.RecentFiles, true);
+        }
+
         internal void WalkDirectoryTree(System.IO.DirectoryInfo root, SampleFileEntry rootProperty)
         {
             try
@@ -654,6 +666,11 @@ private void HandleRegularCommand(StartPageListItem item)
         private void HandleFilePath(StartPageListItem item)
         {
             var path = item.ContextData;
+            if (HandleMissingFilePath(path))
+            {
+                return;
+            }
+
             // Listed templates: use the same open path as the template file-picker (ShowOpenTemplateDialog),
             // i.e. open as a new graph from the file contents, not as the saved template path on disk.
             object openArg = IsTemplateFilePath(path)
@@ -671,6 +688,38 @@ private bool IsTemplateFilePath(string path)
                 string.Equals(template.ContextData, path, StringComparison.OrdinalIgnoreCase));
         }
 
+        internal bool HandleMissingFilePath(string path)
+        {
+            if (File.Exists(path))
+            {
+                return false;
+            }
+
+            DynamoMessageBox.Show(
+                DynamoViewModel.Owner,
+                string.Format(Resources.MessageHomeFileMissing.Replace("\\n", Environment.NewLine), path),
+                Resources.MessageErrorOpeningFileGeneral,
+                MessageBoxButton.OK,
+                MessageBoxImage.Warning);
+
+            RemoveMissingFilePath(RecentFiles, path);
+            RemoveMissingFilePath(TemplateFiles, path);
+
+            return true;
+        }
+
+        private static void RemoveMissingFilePath(ObservableCollection<StartPageListItem> files, string path)
+        {
+            var missingFiles = files
+                .Where(file => string.Equals(file.ContextData, path, StringComparison.OrdinalIgnoreCase))
+                .ToList();
+
+            foreach (var missingFile in missingFiles)
+            {
+                files.Remove(missingFile);
+            }
+        }
+
         private void HandleExternalUrl(StartPageListItem item)
         {
             System.Diagnostics.Process.Start(new ProcessStartInfo(item.ContextData) { UseShellExecute = true });

src/DynamoCoreWpf/DynamoCoreWpf.csproj

@@ -59,7 +59,7 @@
 
     <Target Name="NpmRunBuildHomePage" BeforeTargets="BeforeBuild">
         <PropertyGroup>
-            <PackageVersion>1.0.31</PackageVersion>
+            <PackageVersion>1.0.32</PackageVersion>
             <PackageName>DynamoHome</PackageName>
         </PropertyGroup>
         <Exec Command="$(PowerShellCommand) -ExecutionPolicy Bypass -File &quot;$(SolutionDir)pkgexist.ps1&quot; &quot;$(PackageName)&quot; &quot;$(PackageVersion)&quot;" ConsoleToMSBuild="true">

src/DynamoCoreWpf/Properties/Resources.en-US.resx

@@ -4180,6 +4180,9 @@ To make this file into a new template, save it to a different folder, then move
   <data name="MessageErrorOpeningInvalidPath" xml:space="preserve">
     <value>Invalid file path provided. In case the file is archived, please make sure to extract it before opening.\n{0}</value>
   </data>
+  <data name="MessageHomeFileMissing" xml:space="preserve">
+    <value>This file is no longer available. It may have been moved, renamed, or deleted.\n{0}</value>
+  </data>
   <data name="GroupContextMenuFreezeGroup" xml:space="preserve">
     <value>Freeze Group</value>
   </data>

src/DynamoCoreWpf/Properties/Resources.resx

@@ -4171,6 +4171,9 @@ To make this file into a new template, save it to a different folder, then move
   <data name="MessageErrorOpeningInvalidPath" xml:space="preserve">
     <value>Invalid file path provided. In case the file is archived, please make sure to extract it before opening.\n{0}</value>
   </data>
+  <data name="MessageHomeFileMissing" xml:space="preserve">
+    <value>This file is no longer available. It may have been moved, renamed, or deleted.\n{0}</value>
+  </data>
   <data name="GroupContextMenuFreezeGroup" xml:space="preserve">
     <value>Freeze Group</value>
   </data>

src/DynamoCoreWpf/Views/HomePage/HomePage.xaml.cs

@@ -124,11 +124,20 @@ private void OnDataContextChanged(object sender, DependencyPropertyChangedEventA
             }
         }
 
-        private void DynamoViewModel_PropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e)
+        private async void DynamoViewModel_PropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e)
         {
             if(e.PropertyName == nameof(startPage.DynamoViewModel.ShowStartPage) && dynWebView?.CoreWebView2 != null)
             {
-                dynWebView.CoreWebView2.ExecuteScriptAsync(@$"window.setShowStartPageChanged('{startPage.DynamoViewModel.ShowStartPage}')");
+                if (startPage.DynamoViewModel.ShowStartPage)
+                {
+                    startPage.RefreshTemplateFiles();
+                    startPage.RefreshRecentFiles();
+
+                    await SendTemplateData();
+                    await SendRecentGraphsData();
+                }
+
+                await dynWebView.CoreWebView2.ExecuteScriptAsync(@$"window.setShowStartPageChanged('{startPage.DynamoViewModel.ShowStartPage}')");
             }
         }
 
@@ -338,11 +347,8 @@ private async Task SendSamplesData()
         /// </summary>
         private async Task SendTemplateData()
         {
-            var items = startPage.TemplateFiles?.DistinctBy(x => x.ContextData).ToList();
-            if (items != null && items.Any())
-            {
-                await LoadTemplates(items);
-            }
+            var items = startPage.TemplateFiles?.DistinctBy(x => x.ContextData).ToList() ?? new List<StartPageListItem>();
+            await LoadTemplates(items);
         }
 
         private async Task SendRecentGraphsData()
@@ -361,14 +367,12 @@ private async Task SendRecentGraphsData()
             }
 
             // Load recent files
-            var recentFiles = startPage.RecentFiles?.DistinctBy(x => x.ContextData).ToList();
-            if (recentFiles != null && recentFiles.Any())
-            {
-                await LoadGraphs(recentFiles);
-            }
+            var recentFiles = startPage.RecentFiles?.DistinctBy(x => x.ContextData).ToList() ?? new List<StartPageListItem>();
+            await LoadGraphs(recentFiles);
 
             if (startPage.DynamoViewModel != null && startPage.DynamoViewModel.RecentFiles != null)
             {
+                startPage.DynamoViewModel.RecentFiles.CollectionChanged -= RecentFiles_CollectionChanged;
                 startPage.DynamoViewModel.RecentFiles.CollectionChanged += RecentFiles_CollectionChanged;
             }
         }
@@ -542,6 +546,16 @@ internal void OpenFile(string path)
                 return;
             }
 
+            if (startPage.HandleMissingFilePath(path))
+            {
+                var recentFiles = startPage.RecentFiles?.DistinctBy(x => x.ContextData).ToList() ?? new List<StartPageListItem>();
+                var templateFiles = startPage.TemplateFiles?.DistinctBy(x => x.ContextData).ToList() ?? new List<StartPageListItem>();
+
+                _ = LoadGraphs(recentFiles);
+                _ = LoadTemplates(templateFiles);
+                return;
+            }
+
             var dvm = this.startPage.DynamoViewModel;
             var openArg = IsListedHomePageTemplate(path)
                 ? (object)Tuple.Create(path, false, true)