Get rid of singletons, replace with DI: DockWorkspace

ILSpy/App.xaml.cs

@@ -86,7 +86,7 @@ namespace ICSharpCode.ILSpy
 			if (!InitializeDependencyInjection(settingsService))
 			{
 				// There is something completely wrong with DI, probably some service registration is missing => nothing we can do to recover, so stop and shut down.
-				Exit += (_, _) => MessageBox.Show(StartupExceptions.FormatExceptions(), "Sorry we crashed!");
+				Exit += (_, _) => MessageBox.Show(StartupExceptions.FormatExceptions(), "Sorry we crashed!", MessageBoxButton.OK, MessageBoxImage.Error, MessageBoxResult.OK, MessageBoxOptions.DefaultDesktopOnly);
 				Shutdown(1);
 				return;
 			}

ILSpy/AssemblyTree/AssemblyTreeModel.cs

@@ -264,7 +264,7 @@ namespace ICSharpCode.ILSpy.AssemblyTree
 				{
 					AvalonEditTextOutput output = new AvalonEditTextOutput();
 					output.Write($"Cannot find '{navigateTo}' in command line specified assemblies.");
-					DockWorkspace.Instance.ShowText(output);
+					DockWorkspace.ShowText(output);
 				}
 			}
 			else if (relevantAssemblies.Count == 1)
@@ -304,7 +304,7 @@ namespace ICSharpCode.ILSpy.AssemblyTree
 					}
 					else
 					{
-						DockWorkspace.Instance.ActiveTabPage.ShowTextView(aboutPage.Display);
+						DockWorkspace.ActiveTabPage.ShowTextView(aboutPage.Display);
 					}
 				}
 			}
@@ -405,8 +405,8 @@ namespace ICSharpCode.ILSpy.AssemblyTree
 			{
 				output.Title = "Startup errors";
 
-				DockWorkspace.Instance.AddTabPage();
-				DockWorkspace.Instance.ShowText(output);
+				DockWorkspace.AddTabPage();
+				DockWorkspace.ShowText(output);
 			}
 		}
 
@@ -524,7 +524,7 @@ namespace ICSharpCode.ILSpy.AssemblyTree
 
 			if (inNewTabPage)
 			{
-				DockWorkspace.Instance.AddTabPage();
+				DockWorkspace.AddTabPage();
 				SelectedItem = null;
 			}
 
@@ -739,7 +739,7 @@ namespace ICSharpCode.ILSpy.AssemblyTree
 			}
 			else
 			{
-				var activeTabPage = DockWorkspace.Instance.ActiveTabPage;
+				var activeTabPage = DockWorkspace.ActiveTabPage;
 
 				if (!isNavigatingHistory)
 				{
@@ -787,7 +787,7 @@ namespace ICSharpCode.ILSpy.AssemblyTree
 
 		public void DecompileSelectedNodes(DecompilerTextViewState? newState = null)
 		{
-			var activeTabPage = DockWorkspace.Instance.ActiveTabPage;
+			var activeTabPage = DockWorkspace.ActiveTabPage;
 
 			activeTabPage.SupportsLanguageSwitching = true;
 
@@ -809,7 +809,7 @@ namespace ICSharpCode.ILSpy.AssemblyTree
 
 		public void RefreshDecompiledView()
 		{
-			DecompileSelectedNodes(DockWorkspace.Instance.ActiveTabPage.GetState() as DecompilerTextViewState);
+			DecompileSelectedNodes(DockWorkspace.ActiveTabPage.GetState() as DecompilerTextViewState);
 		}
 
 		public Language CurrentLanguage => languageService.Language;
@@ -830,7 +830,7 @@ namespace ICSharpCode.ILSpy.AssemblyTree
 			{
 				isNavigatingHistory = true;
 
-				TabPageModel tabPage = DockWorkspace.Instance.ActiveTabPage;
+				TabPageModel tabPage = DockWorkspace.ActiveTabPage;
 				var state = tabPage.GetState();
 				if (state != null)
 					history.UpdateCurrent(new NavigationState(tabPage, state));
@@ -838,10 +838,10 @@ namespace ICSharpCode.ILSpy.AssemblyTree
 
 				TabPageModel activeTabPage = newState.TabPage;
 
-				if (!DockWorkspace.Instance.TabPages.Contains(activeTabPage))
-					DockWorkspace.Instance.AddTabPage(activeTabPage);
+				if (!DockWorkspace.TabPages.Contains(activeTabPage))
+					DockWorkspace.AddTabPage(activeTabPage);
 				else
-					DockWorkspace.Instance.ActiveTabPage = activeTabPage;
+					DockWorkspace.ActiveTabPage = activeTabPage;
 
 				SelectNodes(newState.TreeNodes);
 			}
@@ -861,13 +861,13 @@ namespace ICSharpCode.ILSpy.AssemblyTree
 			{
 				if (inNewTabPage)
 				{
-					DockWorkspace.Instance.AddTabPage();
+					DockWorkspace.AddTabPage();
 				}
 
 				if (e.Uri.Host == "aboutpage")
 				{
 					RecordHistory();
-					DockWorkspace.Instance.ActiveTabPage.ShowTextView(aboutPage.Display);
+					DockWorkspace.ActiveTabPage.ShowTextView(aboutPage.Display);
 					e.Handled = true;
 					return;
 				}
@@ -891,7 +891,7 @@ namespace ICSharpCode.ILSpy.AssemblyTree
 					}
 				}
 				RecordHistory();
-				DockWorkspace.Instance.ShowText(output);
+				DockWorkspace.ShowText(output);
 				e.Handled = true;
 			}
 
@@ -899,7 +899,7 @@ namespace ICSharpCode.ILSpy.AssemblyTree
 			{
 				if (isNavigatingHistory)
 					return;
-				TabPageModel tabPage = DockWorkspace.Instance.ActiveTabPage;
+				TabPageModel tabPage = DockWorkspace.ActiveTabPage;
 				var currentState = tabPage.GetState();
 				if (currentState != null)
 					history.UpdateCurrent(new NavigationState(tabPage, currentState));

ILSpy/Commands/DecompileAllCommand.cs

@@ -38,7 +38,7 @@ namespace ICSharpCode.ILSpy
 {
 	[ExportMainMenuCommand(ParentMenuID = nameof(Resources._File), Header = nameof(Resources.DEBUGDecompile), MenuCategory = nameof(Resources.Open), MenuOrder = 2.5)]
 	[Shared]
-	sealed class DecompileAllCommand(AssemblyTreeModel assemblyTreeModel, LanguageService languageService) : SimpleCommand
+	sealed class DecompileAllCommand(AssemblyTreeModel assemblyTreeModel, DockWorkspace dockWorkspace) : SimpleCommand
 	{
 		public override bool CanExecute(object parameter)
 		{
@@ -47,7 +47,7 @@ namespace ICSharpCode.ILSpy
 
 		public override void Execute(object parameter)
 		{
-			Docking.DockWorkspace.Instance.RunWithCancellation(ct => Task<AvalonEditTextOutput>.Factory.StartNew(() => {
+			dockWorkspace.RunWithCancellation(ct => Task<AvalonEditTextOutput>.Factory.StartNew(() => {
 				AvalonEditTextOutput output = new AvalonEditTextOutput();
 				Parallel.ForEach(
 					Partitioner.Create(assemblyTreeModel.AssemblyList.GetAssemblies(), loadBalance: true),
@@ -61,7 +61,7 @@ namespace ICSharpCode.ILSpy
 							{
 								try
 								{
-									var options = DockWorkspace.Instance.ActiveTabPage.CreateDecompilationOptions();
+									var options = dockWorkspace.ActiveTabPage.CreateDecompilationOptions();
 									options.CancellationToken = ct;
 									options.FullDecompilation = true;
 									new CSharpLanguage().DecompileAssembly(asm, new PlainTextOutput(writer), options);
@@ -85,20 +85,19 @@ namespace ICSharpCode.ILSpy
 						}
 					});
 				return output;
-			}, ct)).Then(output => Docking.DockWorkspace.Instance.ShowText(output)).HandleExceptions();
+			}, ct)).Then(dockWorkspace.ShowText).HandleExceptions();
 		}
 	}
 
 	[ExportMainMenuCommand(ParentMenuID = nameof(Resources._File), Header = nameof(Resources.DEBUGDecompile100x), MenuCategory = nameof(Resources.Open), MenuOrder = 2.6)]
 	[Shared]
-	sealed class Decompile100TimesCommand(AssemblyTreeModel assemblyTreeModel, LanguageService languageService) : SimpleCommand
+	sealed class Decompile100TimesCommand(AssemblyTreeModel assemblyTreeModel, LanguageService languageService, DockWorkspace dockWorkspace) : SimpleCommand
 	{
 		public override void Execute(object parameter)
 		{
 			const int numRuns = 100;
 			var language = languageService.Language;
 			var nodes = assemblyTreeModel.SelectedNodes.ToArray();
-			DockWorkspace dockWorkspace = DockWorkspace.Instance;
 			var options = dockWorkspace.ActiveTabPage.CreateDecompilationOptions();
 			dockWorkspace.RunWithCancellation(ct => Task<AvalonEditTextOutput>.Factory.StartNew(() => {
 				options.CancellationToken = ct;

ILSpy/Commands/DecompileInNewViewCommand.cs

@@ -35,15 +35,8 @@ namespace ICSharpCode.ILSpy.Commands
 {
 	[ExportContextMenuEntry(Header = nameof(Resources.DecompileToNewPanel), InputGestureText = "MMB", Icon = "images/Search", Category = nameof(Resources.Analyze), Order = 90)]
 	[Shared]
-	internal sealed class DecompileInNewViewCommand : IContextMenuEntry
+	internal sealed class DecompileInNewViewCommand(AssemblyTreeModel assemblyTreeModel, DockWorkspace dockWorkspace) : IContextMenuEntry
 	{
-		private readonly AssemblyTreeModel assemblyTreeModel;
-
-		public DecompileInNewViewCommand(AssemblyTreeModel assemblyTreeModel)
-		{
-			this.assemblyTreeModel = assemblyTreeModel;
-		}
-
 		public bool IsVisible(TextViewContext context)
 		{
 			return context.SelectedTreeNodes != null || context.Reference?.Reference is IEntity;
@@ -56,11 +49,11 @@ namespace ICSharpCode.ILSpy.Commands
 
 		public void Execute(TextViewContext context)
 		{
-			var activePane = DockWorkspace.Instance.ActivePane;
+			var activePane = dockWorkspace.ActivePane;
 
 			DecompileNodes(GetNodes(context).ToArray());
 
-			DockWorkspace.Instance.ActivePane = activePane;
+			dockWorkspace.ActivePane = activePane;
 		}
 
 		IEnumerable<ILSpyTreeNode> GetNodes(TextViewContext context)
@@ -98,7 +91,7 @@ namespace ICSharpCode.ILSpy.Commands
 			if (nodes.Length == 0)
 				return;
 
-			DockWorkspace.Instance.AddTabPage();
+			dockWorkspace.AddTabPage();
 
 			if (assemblyTreeModel.SelectedItems.SequenceEqual(nodes))
 				assemblyTreeModel.DecompileSelectedNodes();

ILSpy/Commands/DisassembleAllCommand.cs

@@ -25,6 +25,7 @@ using System.Diagnostics;
 using System.Threading.Tasks;
 
 using ICSharpCode.ILSpy.AssemblyTree;
+using ICSharpCode.ILSpy.Docking;
 using ICSharpCode.ILSpy.Properties;
 using ICSharpCode.ILSpy.TextView;
 using ICSharpCode.ILSpy.ViewModels;
@@ -33,7 +34,7 @@ namespace ICSharpCode.ILSpy
 {
 	[ExportMainMenuCommand(ParentMenuID = nameof(Resources._File), Header = nameof(Resources.DEBUGDisassemble), MenuCategory = nameof(Resources.Open), MenuOrder = 2.5)]
 	[Shared]
-	sealed class DisassembleAllCommand(AssemblyTreeModel assemblyTreeModel, LanguageService languageService) : SimpleCommand
+	sealed class DisassembleAllCommand(AssemblyTreeModel assemblyTreeModel, DockWorkspace dockWorkspace) : SimpleCommand
 	{
 		public override bool CanExecute(object parameter)
 		{
@@ -42,8 +43,6 @@ namespace ICSharpCode.ILSpy
 
 		public override void Execute(object parameter)
 		{
-			var dockWorkspace = Docking.DockWorkspace.Instance;
-
 			dockWorkspace.RunWithCancellation(ct => Task<AvalonEditTextOutput>.Factory.StartNew(() => {
 				AvalonEditTextOutput output = new();
 				Parallel.ForEach(
@@ -61,7 +60,7 @@ namespace ICSharpCode.ILSpy
 									var options = dockWorkspace.ActiveTabPage.CreateDecompilationOptions();
 									options.FullDecompilation = true;
 									options.CancellationToken = ct;
-									new ILLanguage().DecompileAssembly(asm, new Decompiler.PlainTextOutput(writer), options);
+									new ILLanguage(dockWorkspace).DecompileAssembly(asm, new Decompiler.PlainTextOutput(writer), options);
 								}
 								catch (Exception ex)
 								{

ILSpy/Commands/ExtractPackageEntryContextMenuEntry.cs

@@ -25,6 +25,7 @@ using System.Threading.Tasks;
 
 using ICSharpCode.Decompiler;
 using ICSharpCode.Decompiler.CSharp.ProjectDecompiler;
+using ICSharpCode.ILSpy.Docking;
 using ICSharpCode.ILSpy.Properties;
 using ICSharpCode.ILSpy.TextView;
 using ICSharpCode.ILSpy.TreeNodes;
@@ -36,7 +37,7 @@ namespace ICSharpCode.ILSpy
 {
 	[ExportContextMenuEntry(Header = nameof(Resources.ExtractPackageEntry), Category = nameof(Resources.Save), Icon = "Images/Save")]
 	[Shared]
-	sealed class ExtractPackageEntryContextMenuEntry : IContextMenuEntry
+	sealed class ExtractPackageEntryContextMenuEntry(DockWorkspace dockWorkspace) : IContextMenuEntry
 	{
 		public void Execute(TextViewContext context)
 		{
@@ -61,7 +62,7 @@ namespace ICSharpCode.ILSpy
 			if (selectedNodes.Length > 1)
 				outputFolderOrFileName = Path.GetDirectoryName(outputFolderOrFileName);
 
-			Docking.DockWorkspace.Instance.RunWithCancellation(ct => Task<AvalonEditTextOutput>.Factory.StartNew(() => {
+			dockWorkspace.RunWithCancellation(ct => Task<AvalonEditTextOutput>.Factory.StartNew(() => {
 				AvalonEditTextOutput output = new AvalonEditTextOutput();
 				Stopwatch stopwatch = Stopwatch.StartNew();
 				stopwatch.Stop();
@@ -83,7 +84,7 @@ namespace ICSharpCode.ILSpy
 				output.AddButton(null, Resources.OpenExplorer, delegate { Process.Start("explorer", "/select,\"" + fileName + "\""); });
 				output.WriteLine();
 				return output;
-			}, ct)).Then(output => Docking.DockWorkspace.Instance.ShowText(output)).HandleExceptions();
+			}, ct)).Then(dockWorkspace.ShowText).HandleExceptions();
 		}
 
 		void SaveEntry(ITextOutput output, PackageEntry entry, string targetFileName)

ILSpy/Commands/GeneratePdbContextMenuEntry.cs

@@ -43,14 +43,14 @@ namespace ICSharpCode.ILSpy
 {
 	[ExportContextMenuEntry(Header = nameof(Resources.GeneratePortable))]
 	[Shared]
-	class GeneratePdbContextMenuEntry(LanguageService languageService) : IContextMenuEntry
+	class GeneratePdbContextMenuEntry(LanguageService languageService, DockWorkspace dockWorkspace) : IContextMenuEntry
 	{
 		public void Execute(TextViewContext context)
 		{
 			var assembly = (context.SelectedTreeNodes?.FirstOrDefault() as AssemblyTreeNode)?.LoadedAssembly;
 			if (assembly == null)
 				return;
-			GeneratePdbForAssembly(assembly, languageService);
+			GeneratePdbForAssembly(assembly, languageService, dockWorkspace);
 		}
 
 		public bool IsEnabled(TextViewContext context) => true;
@@ -62,7 +62,7 @@ namespace ICSharpCode.ILSpy
 				&& tn.LoadedAssembly.IsLoadedAsValidAssembly;
 		}
 
-		internal static void GeneratePdbForAssembly(LoadedAssembly assembly, LanguageService languageService)
+		internal static void GeneratePdbForAssembly(LoadedAssembly assembly, LanguageService languageService, DockWorkspace dockWorkspace)
 		{
 			var file = assembly.GetMetadataFileOrNull() as PEFile;
 			if (!PortablePdbWriter.HasCodeViewDebugDirectoryEntry(file))
@@ -76,7 +76,6 @@ namespace ICSharpCode.ILSpy
 			dlg.InitialDirectory = Path.GetDirectoryName(assembly.FileName);
 			if (dlg.ShowDialog() != true)
 				return;
-			DockWorkspace dockWorkspace = DockWorkspace.Instance;
 			DecompilationOptions options = dockWorkspace.ActiveTabPage.CreateDecompilationOptions();
 			string fileName = dlg.FileName;
 			dockWorkspace.RunWithCancellation(ct => Task<AvalonEditTextOutput>.Factory.StartNew(() => {
@@ -104,13 +103,13 @@ namespace ICSharpCode.ILSpy
 				output.AddButton(null, Resources.OpenExplorer, delegate { Process.Start("explorer", "/select,\"" + fileName + "\""); });
 				output.WriteLine();
 				return output;
-			}, ct)).Then(output => Docking.DockWorkspace.Instance.ShowText(output)).HandleExceptions();
+			}, ct)).Then(dockWorkspace.ShowText).HandleExceptions();
 		}
 	}
 
 	[ExportMainMenuCommand(ParentMenuID = nameof(Resources._File), Header = nameof(Resources.GeneratePortable), MenuCategory = nameof(Resources.Save))]
 	[Shared]
-	class GeneratePdbMainMenuEntry(AssemblyTreeModel assemblyTreeModel, LanguageService languageService) : SimpleCommand
+	class GeneratePdbMainMenuEntry(AssemblyTreeModel assemblyTreeModel, LanguageService languageService, DockWorkspace dockWorkspace) : SimpleCommand
 	{
 		public override bool CanExecute(object parameter)
 		{
@@ -124,7 +123,7 @@ namespace ICSharpCode.ILSpy
 			var assembly = (assemblyTreeModel.SelectedNodes?.FirstOrDefault() as AssemblyTreeNode)?.LoadedAssembly;
 			if (assembly == null)
 				return;
-			GeneratePdbContextMenuEntry.GeneratePdbForAssembly(assembly, languageService);
+			GeneratePdbContextMenuEntry.GeneratePdbForAssembly(assembly, languageService, dockWorkspace);
 		}
 	}
 }

ILSpy/Commands/Pdb2XmlCommand.cs

@@ -27,6 +27,7 @@ using System.Threading.Tasks;
 using ICSharpCode.AvalonEdit.Highlighting;
 using ICSharpCode.Decompiler;
 using ICSharpCode.ILSpy.AssemblyTree;
+using ICSharpCode.ILSpy.Docking;
 using ICSharpCode.ILSpy.Properties;
 using ICSharpCode.ILSpy.TextView;
 using ICSharpCode.ILSpy.TreeNodes;
@@ -37,7 +38,7 @@ namespace ICSharpCode.ILSpy
 {
 	[ExportMainMenuCommand(ParentMenuID = nameof(Resources._File), Header = nameof(Resources.DEBUGDumpPDBAsXML), MenuCategory = nameof(Resources.Open), MenuOrder = 2.6)]
 	[Shared]
-	sealed class Pdb2XmlCommand(AssemblyTreeModel assemblyTreeModel) : SimpleCommand
+	sealed class Pdb2XmlCommand(AssemblyTreeModel assemblyTreeModel, DockWorkspace dockWorkspace) : SimpleCommand
 	{
 		public override bool CanExecute(object parameter)
 		{
@@ -48,14 +49,14 @@ namespace ICSharpCode.ILSpy
 
 		public override void Execute(object parameter)
 		{
-			Execute(assemblyTreeModel.SelectedNodes.OfType<AssemblyTreeNode>());
+			Execute(assemblyTreeModel.SelectedNodes.OfType<AssemblyTreeNode>(), dockWorkspace);
 		}
 
-		internal static void Execute(IEnumerable<AssemblyTreeNode> nodes)
+		internal static void Execute(IEnumerable<AssemblyTreeNode> nodes, DockWorkspace dockWorkspace)
 		{
 			var highlighting = HighlightingManager.Instance.GetDefinitionByExtension(".xml");
 			var options = PdbToXmlOptions.IncludeEmbeddedSources | PdbToXmlOptions.IncludeMethodSpans | PdbToXmlOptions.IncludeTokens;
-			Docking.DockWorkspace.Instance.RunWithCancellation(ct => Task<AvalonEditTextOutput>.Factory.StartNew(() => {
+			dockWorkspace.RunWithCancellation(ct => Task<AvalonEditTextOutput>.Factory.StartNew(() => {
 				AvalonEditTextOutput output = new AvalonEditTextOutput();
 				var writer = new TextOutputWriter(output);
 				foreach (var node in nodes)
@@ -68,17 +69,17 @@ namespace ICSharpCode.ILSpy
 						PdbToXmlConverter.ToXml(writer, pdbStream, peStream, options);
 				}
 				return output;
-			}, ct)).Then(output => Docking.DockWorkspace.Instance.ShowNodes(output, null, highlighting)).HandleExceptions();
+			}, ct)).Then(output => dockWorkspace.ShowNodes(output, null, highlighting)).HandleExceptions();
 		}
 	}
 
 	[ExportContextMenuEntry(Header = nameof(Resources.DEBUGDumpPDBAsXML))]
 	[Shared]
-	class Pdb2XmlCommandContextMenuEntry : IContextMenuEntry
+	class Pdb2XmlCommandContextMenuEntry(DockWorkspace dockWorkspace) : IContextMenuEntry
 	{
 		public void Execute(TextViewContext context)
 		{
-			Pdb2XmlCommand.Execute(context.SelectedTreeNodes.OfType<AssemblyTreeNode>());
+			Pdb2XmlCommand.Execute(context.SelectedTreeNodes.OfType<AssemblyTreeNode>(), dockWorkspace);
 		}
 
 		public bool IsEnabled(TextViewContext context) => true;

ILSpy/Commands/SaveCodeContextMenuEntry.cs

@@ -23,6 +23,7 @@ using System.IO;
 using System.Linq;
 using System.Windows;
 
+using ICSharpCode.ILSpy.Docking;
 using ICSharpCode.ILSpy.Properties;
 using ICSharpCode.ILSpy.TreeNodes;
 using ICSharpCode.ILSpy.ViewModels;
@@ -35,11 +36,11 @@ namespace ICSharpCode.ILSpy.TextView
 {
 	[ExportContextMenuEntry(Header = nameof(Resources._SaveCode), Category = nameof(Resources.Save), Icon = "Images/Save")]
 	[Shared]
-	sealed class SaveCodeContextMenuEntry(LanguageService languageService) : IContextMenuEntry
+	sealed class SaveCodeContextMenuEntry(LanguageService languageService, DockWorkspace dockWorkspace) : IContextMenuEntry
 	{
 		public void Execute(TextViewContext context)
 		{
-			Execute(context.SelectedTreeNodes, languageService);
+			Execute(context.SelectedTreeNodes, languageService, dockWorkspace);
 		}
 
 		public bool IsEnabled(TextViewContext context) => true;
@@ -57,10 +58,8 @@ namespace ICSharpCode.ILSpy.TextView
 				|| (selectedNodes.Count > 1 && (selectedNodes.All(n => n is AssemblyTreeNode) || selectedNodes.All(n => n is IMemberTreeNode)));
 		}
 
-		public static void Execute(IReadOnlyList<SharpTreeNode> selectedNodes, LanguageService languageService)
+		public static void Execute(IReadOnlyList<SharpTreeNode> selectedNodes, LanguageService languageService, DockWorkspace dockWorkspace)
 		{
-			var dockWorkspace = Docking.DockWorkspace.Instance;
-
 			var currentLanguage = languageService.Language;
 			var tabPage = dockWorkspace.ActiveTabPage;
 			tabPage.ShowTextView(textView => {
@@ -80,7 +79,7 @@ namespace ICSharpCode.ILSpy.TextView
 						var assemblies = selectedNodes.OfType<AssemblyTreeNode>()
 							.Select(n => n.LoadedAssembly)
 							.Where(a => a.IsLoadedAsValidAssembly).ToArray();
-						SolutionWriter.CreateSolution(textView, selectedPath, currentLanguage, assemblies);
+						SolutionWriter.CreateSolution(tabPage, textView, selectedPath, currentLanguage, assemblies);
 					}
 					return;
 				}

ILSpy/Commands/SaveCommand.cs

@@ -21,6 +21,7 @@ using System.Linq;
 using System.Windows.Input;
 
 using ICSharpCode.ILSpy.AssemblyTree;
+using ICSharpCode.ILSpy.Docking;
 using ICSharpCode.ILSpy.Properties;
 using ICSharpCode.ILSpy.TextView;
 
@@ -28,7 +29,7 @@ namespace ICSharpCode.ILSpy
 {
 	[ExportMainMenuCommand(ParentMenuID = nameof(Resources._File), Header = nameof(Resources._SaveCode), MenuIcon = "Images/Save", MenuCategory = nameof(Resources.Save), MenuOrder = 0)]
 	[Shared]
-	sealed class SaveCommand(AssemblyTreeModel assemblyTreeModel, LanguageService languageService) : CommandWrapper(ApplicationCommands.Save)
+	sealed class SaveCommand(AssemblyTreeModel assemblyTreeModel, LanguageService languageService, DockWorkspace dockWorkspace) : CommandWrapper(ApplicationCommands.Save)
 	{
 		protected override void OnCanExecute(object sender, CanExecuteRoutedEventArgs e)
 		{
@@ -38,7 +39,7 @@ namespace ICSharpCode.ILSpy
 
 		protected override void OnExecute(object sender, ExecutedRoutedEventArgs e)
 		{
-			SaveCodeContextMenuEntry.Execute(assemblyTreeModel.SelectedNodes.ToList(), languageService);
+			SaveCodeContextMenuEntry.Execute(assemblyTreeModel.SelectedNodes.ToList(), languageService, dockWorkspace);
 		}
 	}
 }

ILSpy/Commands/ShowPane.cs

@@ -3,39 +3,23 @@ using ICSharpCode.ILSpy.ViewModels;
 
 namespace ICSharpCode.ILSpy.Commands
 {
-	class ToolPaneCommand : SimpleCommand
+	class ToolPaneCommand(string contentId, DockWorkspace dockWorkspace) : SimpleCommand
 	{
-		readonly string contentId;
-
-		public ToolPaneCommand(string contentId)
-		{
-			this.contentId = contentId;
-		}
-
 		public override void Execute(object parameter)
 		{
-			DockWorkspace.Instance.ShowToolPane(contentId);
+			dockWorkspace.ShowToolPane(contentId);
 		}
 	}
 
-	class TabPageCommand : SimpleCommand
+	class TabPageCommand(TabPageModel model, DockWorkspace dockWorkspace) : SimpleCommand
 	{
-		readonly TabPageModel model;
-
-		public TabPageCommand(TabPageModel model)
-		{
-			this.model = model;
-		}
-
 		public override void Execute(object parameter)
 		{
-			var workspace = DockWorkspace.Instance;
-
 			// ensure the tab control is focused before setting the active tab page, else the tab will not be focused
-			workspace.ActiveTabPage?.Focus();
+			dockWorkspace.ActiveTabPage?.Focus();
 			// reset first, else clicking on the already active tab will not focus the tab and the menu checkmark will not be updated
-			workspace.ActiveTabPage = null;
-			workspace.ActiveTabPage = model;
+			dockWorkspace.ActiveTabPage = null;
+			dockWorkspace.ActiveTabPage = model;
 		}
 	}
 }

ILSpy/Controls/ZoomScrollViewer.cs

@@ -176,21 +176,4 @@ namespace ICSharpCode.ILSpy.Controls
 				return val;
 		}
 	}
-
-	sealed class IsNormalZoomConverter : IValueConverter
-	{
-		public static readonly IsNormalZoomConverter Instance = new IsNormalZoomConverter();
-
-		public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
-		{
-			if (parameter is bool && (bool)parameter)
-				return true;
-			return ((double)value) == 1.0;
-		}
-
-		public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
-		{
-			throw new NotImplementedException();
-		}
-	}
 }

ILSpy/Docking/CloseAllDocumentsCommand.cs

@@ -6,21 +6,21 @@ namespace ICSharpCode.ILSpy.Docking
 {
 	[ExportMainMenuCommand(Header = nameof(Resources.Window_CloseAllDocuments), ParentMenuID = nameof(Resources._Window))]
 	[Shared]
-	class CloseAllDocumentsCommand : SimpleCommand
+	class CloseAllDocumentsCommand(DockWorkspace dockWorkspace) : SimpleCommand
 	{
 		public override void Execute(object parameter)
 		{
-			DockWorkspace.Instance.CloseAllTabs();
+			dockWorkspace.CloseAllTabs();
 		}
 	}
 
 	[ExportMainMenuCommand(Header = nameof(Resources.Window_ResetLayout), ParentMenuID = nameof(Resources._Window))]
 	[Shared]
-	class ResetLayoutCommand : SimpleCommand
+	class ResetLayoutCommand(DockWorkspace dockWorkspace) : SimpleCommand
 	{
 		public override void Execute(object parameter)
 		{
-			DockWorkspace.Instance.ResetLayout();
+			dockWorkspace.ResetLayout();
 		}
 	}
 }

ILSpy/Docking/DockWorkspace.cs

@@ -20,6 +20,7 @@ using System;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using System.Collections.Specialized;
+using System.Composition;
 using System.Linq;
 using System.Reflection;
 using System.Threading;
@@ -43,38 +44,34 @@ using TomsToolbox.Wpf;
 
 namespace ICSharpCode.ILSpy.Docking
 {
+	[Export]
+	[Shared]
 	public class DockWorkspace : ObservableObject, ILayoutUpdateStrategy
 	{
-		private static readonly IExportProvider exportProvider = App.ExportProvider;
+		private readonly IExportProvider exportProvider;
+		
+		private SettingsService SettingsService { get; }
 
-		private static SettingsService SettingsService => exportProvider.GetExportedValue<SettingsService>();
+		private LanguageService LanguageService => exportProvider.GetExportedValue<LanguageService>();
 
-		private static LanguageService LanguageService => exportProvider.GetExportedValue<LanguageService>();
-
-		private static SessionSettings SessionSettings => SettingsService.SessionSettings;
-
-		public static readonly DockWorkspace Instance = new();
+		private SessionSettings SessionSettings { get; }
 
 		private readonly ObservableCollection<TabPageModel> tabPages = [];
 
 		private DockingManager DockingManager => exportProvider.GetExportedValue<DockingManager>();
 
-		AssemblyTreeModel AssemblyTreeModel => exportProvider.GetExportedValue<AssemblyTreeModel>();
+		private AssemblyTreeModel AssemblyTreeModel => exportProvider.GetExportedValue<AssemblyTreeModel>();
 
-		private DockWorkspace()
+		public DockWorkspace(SettingsService settingsService, IExportProvider exportProvider)
 		{
+			this.exportProvider = exportProvider;
+			
+			SettingsService = settingsService;
+			SessionSettings = settingsService.SessionSettings;
+
 			this.tabPages.CollectionChanged += TabPages_CollectionChanged;
 			TabPages = new(tabPages);
 
-			ToolPanes = exportProvider
-				.GetExportedValues<ToolPaneModel>("ToolPane")
-				.OrderBy(item => item.Title)
-				.ToArray()
-				.AsReadOnly();
-
-			// Make sure there is at least one tab open
-			AddTabPage();
-
 			MessageBus<CurrentAssemblyListChangedEventArgs>.Subscribers += (sender, e) => CurrentAssemblyList_Changed(sender, e);
 		}
 
@@ -135,7 +132,11 @@ namespace ICSharpCode.ILSpy.Docking
 
 		public ReadOnlyObservableCollection<TabPageModel> TabPages { get; }
 
-		public ReadOnlyCollection<ToolPaneModel> ToolPanes { get; }
+		public ReadOnlyCollection<ToolPaneModel> ToolPanes => exportProvider
+			.GetExportedValues<ToolPaneModel>("ToolPane")
+			.OrderBy(item => item.Title)
+			.ToArray()
+			.AsReadOnly();
 
 		public bool ShowToolPane(string contentId)
 		{
@@ -188,15 +189,15 @@ namespace ICSharpCode.ILSpy.Docking
 		}
 
 		public PaneModel ActivePane {
-			get => DockingManager?.ActiveContent as PaneModel;
-			set {
-				if (DockingManager is not null)
-					DockingManager.ActiveContent = value;
-			}
+			get => DockingManager.ActiveContent as PaneModel;
+			set => DockingManager.ActiveContent = value;
 		}
 
 		public void InitializeLayout()
 		{
+			// Make sure there is at least one tab open
+			AddTabPage();
+
 			DockingManager.LayoutUpdateStrategy = this;
 			XmlLayoutSerializer serializer = new XmlLayoutSerializer(DockingManager);
 			serializer.LayoutSerializationCallback += LayoutSerializationCallback;

ILSpy/Languages/CSharpILMixedLanguage.cs

@@ -34,6 +34,7 @@ using ICSharpCode.Decompiler.Disassembler;
 using ICSharpCode.Decompiler.Metadata;
 using ICSharpCode.Decompiler.TypeSystem;
 using ICSharpCode.Decompiler.Util;
+using ICSharpCode.ILSpy.Docking;
 using ICSharpCode.ILSpyX;
 using ICSharpCode.ILSpyX.Extensions;
 
@@ -43,7 +44,7 @@ namespace ICSharpCode.ILSpy
 
 	[Export(typeof(Language))]
 	[Shared]
-	class CSharpILMixedLanguage(SettingsService settingsService) : ILLanguage
+	class CSharpILMixedLanguage(SettingsService settingsService, DockWorkspace dockWorkspace) : ILLanguage(dockWorkspace)
 	{
 		public override string Name => "IL with C#";
 

ILSpy/Languages/ILAstLanguage.cs

@@ -26,6 +26,7 @@ using ICSharpCode.Decompiler.IL;
 using ICSharpCode.Decompiler.IL.Transforms;
 using ICSharpCode.Decompiler.Metadata;
 using ICSharpCode.Decompiler.TypeSystem;
+using ICSharpCode.ILSpy.Docking;
 using ICSharpCode.ILSpy.ViewModels;
 using ICSharpCode.ILSpyX;
 
@@ -41,13 +42,6 @@ namespace ICSharpCode.ILSpy
 	{
 		public event EventHandler StepperUpdated;
 
-		protected virtual void OnStepperUpdated(EventArgs e = null)
-		{
-			StepperUpdated?.Invoke(this, e ?? new EventArgs());
-		}
-
-		public Stepper Stepper { get; set; } = new Stepper();
-
 		readonly string name;
 
 		protected ILAstLanguage(string name)
@@ -55,12 +49,19 @@ namespace ICSharpCode.ILSpy
 			this.name = name;
 		}
 
+		protected virtual void OnStepperUpdated(EventArgs e = null)
+		{
+			StepperUpdated?.Invoke(this, e ?? new EventArgs());
+		}
+
+		public Stepper Stepper { get; set; } = new Stepper();
+
 		public override string Name { get { return name; } }
 
-		internal static IEnumerable<ILAstLanguage> GetDebugLanguages()
+		internal static IEnumerable<ILAstLanguage> GetDebugLanguages(DockWorkspace dockWorkspace)
 		{
 			yield return new TypedIL();
-			yield return new BlockIL(CSharpDecompiler.GetILTransforms());
+			yield return new BlockIL(CSharpDecompiler.GetILTransforms(), dockWorkspace);
 		}
 
 		public override string FileExtension {
@@ -78,10 +79,8 @@ namespace ICSharpCode.ILSpy
 			output.WriteLine();
 		}
 
-		class TypedIL : ILAstLanguage
+		class TypedIL() : ILAstLanguage("Typed IL")
 		{
-			public TypedIL() : base("Typed IL") { }
-
 			public override void DecompileMethod(IMethod method, ITextOutput output, DecompilationOptions options)
 			{
 				base.DecompileMethod(method, output, options);
@@ -96,15 +95,8 @@ namespace ICSharpCode.ILSpy
 			}
 		}
 
-		class BlockIL : ILAstLanguage
+		class BlockIL(IReadOnlyList<IILTransform> transforms, DockWorkspace dockWorkspace) : ILAstLanguage("ILAst")
 		{
-			readonly IReadOnlyList<IILTransform> transforms;
-
-			public BlockIL(IReadOnlyList<IILTransform> transforms) : base("ILAst")
-			{
-				this.transforms = transforms;
-			}
-
 			public override void DecompileMethod(IMethod method, ITextOutput output, DecompilationOptions options)
 			{
 				base.DecompileMethod(method, output, options);
@@ -146,7 +138,7 @@ namespace ICSharpCode.ILSpy
 					}
 				}
 				(output as ISmartTextOutput)?.AddButton(Images.ViewCode, "Show Steps", delegate {
-					Docking.DockWorkspace.Instance.ShowToolPane(DebugStepsPaneModel.PaneContentId);
+					dockWorkspace.ShowToolPane(DebugStepsPaneModel.PaneContentId);
 				});
 				output.WriteLine();
 				il.WriteTo(output, DebugSteps.Options);

ILSpy/Languages/ILLanguage.cs

@@ -45,7 +45,7 @@ namespace ICSharpCode.ILSpy
 	/// </remarks>
 	[Export(typeof(Language))]
 	[Shared]
-	public class ILLanguage : Language
+	public class ILLanguage(DockWorkspace dockWorkspace) : Language
 	{
 		protected bool detectControlStructure = true;
 
@@ -199,7 +199,6 @@ namespace ICSharpCode.ILSpy
 		public override RichText GetRichTextTooltip(IEntity entity)
 		{
 			var output = new AvalonEditTextOutput() { IgnoreNewLineAndIndent = true };
-			var dockWorkspace = DockWorkspace.Instance;
 
 			var disasm = CreateDisassembler(output, dockWorkspace.ActiveTabPage.CreateDecompilationOptions());
 			MetadataFile module = entity.ParentModule?.MetadataFile;

ILSpy/Languages/LanguageService.cs

@@ -24,6 +24,7 @@ using System.Collections.ObjectModel;
 using System.Composition;
 using System.Linq;
 
+using ICSharpCode.ILSpy.Docking;
 using ICSharpCode.ILSpyX;
 
 using TomsToolbox.Wpf;
@@ -36,7 +37,7 @@ namespace ICSharpCode.ILSpy
 	{
 		private readonly LanguageSettings languageSettings;
 
-		public LanguageService(IEnumerable<Language> languages, SettingsService settingsService)
+		public LanguageService(IEnumerable<Language> languages, SettingsService settingsService, DockWorkspace dockWorkspace)
 		{
 			languageSettings = settingsService.SessionSettings.LanguageSettings;
 
@@ -44,7 +45,7 @@ namespace ICSharpCode.ILSpy
 
 			sortedLanguages.Sort((a, b) => string.Compare(a.Name, b.Name, StringComparison.Ordinal));
 #if DEBUG
-			sortedLanguages.AddRange(ILAstLanguage.GetDebugLanguages());
+			sortedLanguages.AddRange(ILAstLanguage.GetDebugLanguages(dockWorkspace));
 			sortedLanguages.AddRange(CSharpLanguage.GetDebugLanguages());
 #endif
 			AllLanguages = sortedLanguages.AsReadOnly();

ILSpy/MainWindowViewModel.cs

@@ -29,11 +29,14 @@ namespace ICSharpCode.ILSpy
 {
 	[Export]
 	[Shared]
-	public class MainWindowViewModel(AssemblyTreeModel assemblyTreeModel, AnalyzerTreeViewModel analyzerTreeViewModel, SettingsService settingsService, LanguageService languageService) : ObservableObject
+	public class MainWindowViewModel(AssemblyTreeModel assemblyTreeModel, AnalyzerTreeViewModel analyzerTreeViewModel, SettingsService settingsService, LanguageService languageService, DockWorkspace dockWorkspace) : ObservableObject
 	{
-		public DockWorkspace Workspace => DockWorkspace.Instance;
+		public DockWorkspace Workspace { get; } = dockWorkspace;
+
 		public SessionSettings SessionSettings => settingsService.SessionSettings;
+
 		public LanguageService LanguageService => languageService;
+
 		public AssemblyListManager AssemblyListManager => settingsService.AssemblyListManager;
 
 		public AnalyzeCommand AnalyzeCommand { get; } = new(assemblyTreeModel, analyzerTreeViewModel);

ILSpy/Search/SearchPane.xaml.cs

@@ -554,9 +554,12 @@ namespace ICSharpCode.ILSpy.Search
 	[Shared]
 	sealed class ShowSearchCommand : CommandWrapper
 	{
-		public ShowSearchCommand()
+		private readonly DockWorkspace dockWorkspace;
+
+		public ShowSearchCommand(DockWorkspace dockWorkspace)
 			: base(NavigationCommands.Search)
 		{
+			this.dockWorkspace = dockWorkspace;
 			var gestures = NavigationCommands.Search.InputGestures;
 
 			gestures.Clear();
@@ -566,7 +569,7 @@ namespace ICSharpCode.ILSpy.Search
 
 		protected override void OnExecute(object sender, ExecutedRoutedEventArgs e)
 		{
-			DockWorkspace.Instance.ShowToolPane(SearchPaneModel.PaneContentId);
+			dockWorkspace.ShowToolPane(SearchPaneModel.PaneContentId);
 		}
 	}
 }

ILSpy/SolutionWriter.cs

@@ -47,15 +47,17 @@ namespace ICSharpCode.ILSpy
 		/// to the <paramref name="solutionFilePath"/>. The directory of this file must either
 		/// be empty or not exist.
 		/// </summary>
+		/// <param name="tabPage"></param>
 		/// <param name="textView">A reference to the <see cref="DecompilerTextView"/> instance.</param>
 		/// <param name="solutionFilePath">The target file path of the solution file.</param>
+		/// <param name="language"></param>
 		/// <param name="assemblies">The assembly nodes to decompile.</param>
-		/// 
 		/// <exception cref="ArgumentException">Thrown when <paramref name="solutionFilePath"/> is null,
 		/// an empty or a whitespace string.</exception>
 		/// <exception cref="ArgumentNullException">Thrown when <paramref name="textView"/>> or
 		/// <paramref name="assemblies"/> is null.</exception>
-		public static void CreateSolution(DecompilerTextView textView, string solutionFilePath, Language language, IEnumerable<LoadedAssembly> assemblies)
+		public static void CreateSolution(TabPageModel tabPage, DecompilerTextView textView, string solutionFilePath,
+			Language language, IEnumerable<LoadedAssembly> assemblies)
 		{
 			if (textView == null)
 			{
@@ -75,7 +77,7 @@ namespace ICSharpCode.ILSpy
 			var writer = new SolutionWriter(solutionFilePath);
 
 			textView
-				.RunWithCancellation(ct => writer.CreateSolution(assemblies, language, ct))
+				.RunWithCancellation(ct => writer.CreateSolution(tabPage, assemblies, language, ct))
 				.Then(output => textView.ShowText(output))
 				.HandleExceptions();
 		}
@@ -93,7 +95,7 @@ namespace ICSharpCode.ILSpy
 			projects = new ConcurrentBag<ProjectItem>();
 		}
 
-		async Task<AvalonEditTextOutput> CreateSolution(IEnumerable<LoadedAssembly> assemblies, Language language, CancellationToken ct)
+		async Task<AvalonEditTextOutput> CreateSolution(TabPageModel tabPage, IEnumerable<LoadedAssembly> assemblies, Language language, CancellationToken ct)
 		{
 			var result = new AvalonEditTextOutput();
 
@@ -113,7 +115,7 @@ namespace ICSharpCode.ILSpy
 				// long to decompile.
 				await Task.Run(() => Parallel.ForEach(Partitioner.Create(assemblies),
 					new ParallelOptions { MaxDegreeOfParallelism = Environment.ProcessorCount, CancellationToken = ct },
-					n => WriteProject(n, language, solutionDirectory, ct)))
+					item => WriteProject(tabPage, item, language, solutionDirectory, ct)))
 					.ConfigureAwait(false);
 
 				if (projects.Count == 0)
@@ -175,7 +177,7 @@ namespace ICSharpCode.ILSpy
 			return result;
 		}
 
-		void WriteProject(LoadedAssembly loadedAssembly, Language language, string targetDirectory, CancellationToken ct)
+		void WriteProject(TabPageModel tabPage, LoadedAssembly loadedAssembly, Language language, string targetDirectory, CancellationToken ct)
 		{
 			targetDirectory = Path.Combine(targetDirectory, loadedAssembly.ShortName);
 
@@ -214,7 +216,7 @@ namespace ICSharpCode.ILSpy
 				using (var projectFileWriter = new StreamWriter(projectFileName))
 				{
 					var projectFileOutput = new PlainTextOutput(projectFileWriter);
-					var options = DockWorkspace.Instance.ActiveTabPage.CreateDecompilationOptions();
+					var options = tabPage.CreateDecompilationOptions();
 					options.FullDecompilation = true;
 					options.CancellationToken = ct;
 					options.SaveAsProjectDirectory = targetDirectory;

ILSpy/TaskHelper.cs

@@ -20,6 +20,7 @@ using System;
 using System.Threading;
 using System.Threading.Tasks;
 
+using ICSharpCode.ILSpy.Docking;
 using ICSharpCode.ILSpy.TextView;
 
 namespace ICSharpCode.ILSpy
@@ -200,7 +201,7 @@ namespace ICSharpCode.ILSpy
 			task.Catch<Exception>(exception => App.Current.Dispatcher.BeginInvoke(new Action(delegate {
 				AvalonEditTextOutput output = new();
 				output.Write(exception.ToString());
-				Docking.DockWorkspace.Instance.ShowText(output);
+				App.ExportProvider.GetExportedValue<DockWorkspace>().ShowText(output);
 			}))).IgnoreExceptions();
 		}
 	}

ILSpy/TreeNodes/AssemblyTreeNode.cs

@@ -547,7 +547,7 @@ namespace ICSharpCode.ILSpy.TreeNodes
 			dlg.Filter = language.Name + " project|*" + language.ProjectFileExtension + "|" + language.Name + " single file|*" + language.FileExtension + "|All files|*.*";
 			if (dlg.ShowDialog() == true)
 			{
-				var options = DockWorkspace.Instance.ActiveTabPage.CreateDecompilationOptions();
+				var options = DockWorkspace.ActiveTabPage.CreateDecompilationOptions();
 				options.FullDecompilation = true;
 				if (dlg.FilterIndex == 1)
 				{

ILSpy/TreeNodes/ILSpyTreeNode.cs

@@ -27,6 +27,7 @@ using System.Windows.Threading;
 using ICSharpCode.Decompiler;
 using ICSharpCode.Decompiler.TypeSystem;
 using ICSharpCode.ILSpy.AssemblyTree;
+using ICSharpCode.ILSpy.Docking;
 using ICSharpCode.ILSpyX.Abstractions;
 using ICSharpCode.ILSpyX.TreeView.PlatformAbstractions;
 using ICSharpCode.ILSpyX.TreeView;
@@ -57,6 +58,8 @@ namespace ICSharpCode.ILSpy.TreeNodes
 
 		public static LanguageService LanguageService { get; } = App.ExportProvider.GetExportedValue<LanguageService>();
 
+		public static DockWorkspace DockWorkspace { get; } = App.ExportProvider.GetExportedValue<DockWorkspace>();
+
 		public virtual FilterResult Filter(LanguageSettings settings)
 		{
 			if (string.IsNullOrEmpty(settings.SearchTerm))

ILSpy/TreeNodes/ResourceNodes/ResourceTreeNode.cs

@@ -74,7 +74,7 @@ namespace ICSharpCode.ILSpy.TreeNodes
 			ISmartTextOutput smartOutput = output as ISmartTextOutput;
 			if (smartOutput != null)
 			{
-				smartOutput.AddButton(Images.Save, Resources.Save, delegate { Save(Docking.DockWorkspace.Instance.ActiveTabPage); });
+				smartOutput.AddButton(Images.Save, Resources.Save, delegate { Save(DockWorkspace.ActiveTabPage); });
 				output.WriteLine();
 			}
 		}

ILSpy/TreeNodes/ResourceNodes/ResourcesFileTreeNode.cs

@@ -176,7 +176,7 @@ namespace ICSharpCode.ILSpy.TreeNodes
 		{
 			EnsureLazyChildren();
 			base.Decompile(language, output, options);
-			var textView = (DecompilerTextView)Docking.DockWorkspace.Instance.ActiveTabPage.Content;
+			var textView = (DecompilerTextView)DockWorkspace.ActiveTabPage.Content;
 			if (stringTableEntries.Count != 0)
 			{
 				ISmartTextOutput smartOutput = output as ISmartTextOutput;

ILSpy/Util/MenuService.cs

@@ -38,10 +38,8 @@ namespace ICSharpCode.ILSpy.Util
 {
 	[Export]
 	[Shared]
-	public class MenuService(IExportProvider exportProvider)
+	public class MenuService(IExportProvider exportProvider, DockWorkspace dockWorkspace)
 	{
-		private readonly DockWorkspace dockWorkspace = DockWorkspace.Instance;
-
 		public void Init(Menu mainMenu, ToolBar toolBar, InputBindingCollection inputBindings)
 		{
 			InitMainMenu(mainMenu);
@@ -144,7 +142,7 @@ namespace ICSharpCode.ILSpy.Util
 			windowMenuItem.Items.Clear();
 
 			var toolItems = dockWorkspace.ToolPanes.Select(toolPane => CreateMenuItem(toolPane, inputBindings)).ToArray();
-			var tabItems = dockWorkspace.TabPages.ObservableSelect(tabPage => CreateMenuItem(tabPage, dockWorkspace));
+			var tabItems = dockWorkspace.TabPages.ObservableSelect(tabPage => CreateMenuItem(tabPage));
 
 			var allItems = new ObservableCompositeCollection<Control>(defaultItems, [new Separator()], toolItems, [new Separator()], tabItems);
 
@@ -188,7 +186,7 @@ namespace ICSharpCode.ILSpy.Util
 
 		}
 
-		static Control CreateMenuItem(TabPageModel pane, DockWorkspace dock)
+		Control CreateMenuItem(TabPageModel pane)
 		{
 			var header = new TextBlock {
 				MaxWidth = 200,
@@ -200,13 +198,13 @@ namespace ICSharpCode.ILSpy.Util
 			});
 
 			MenuItem menuItem = new() {
-				Command = new TabPageCommand(pane),
+				Command = new TabPageCommand(pane, dockWorkspace),
 				Header = header,
 				IsCheckable = true
 			};
 
-			menuItem.SetBinding(MenuItem.IsCheckedProperty, new Binding(nameof(dock.ActiveTabPage)) {
-				Source = dock,
+			menuItem.SetBinding(MenuItem.IsCheckedProperty, new Binding(nameof(dockWorkspace.ActiveTabPage)) {
+				Source = dockWorkspace,
 				ConverterParameter = pane,
 				Converter = BinaryOperationConverter.Equality,
 				Mode = BindingMode.OneWay
@@ -215,10 +213,10 @@ namespace ICSharpCode.ILSpy.Util
 			return menuItem;
 		}
 
-		static Control CreateMenuItem(ToolPaneModel pane, InputBindingCollection inputBindings)
+		Control CreateMenuItem(ToolPaneModel pane, InputBindingCollection inputBindings)
 		{
 			MenuItem menuItem = new() {
-				Command = pane.AssociatedCommand ?? new ToolPaneCommand(pane.ContentId),
+				Command = pane.AssociatedCommand ?? new ToolPaneCommand(pane.ContentId, dockWorkspace),
 				Header = pane.Title
 			};
 			var shortcutKey = pane.ShortcutKey;

ILSpy/ViewModels/PaneModel.cs

@@ -22,6 +22,7 @@ using System.Windows;
 using System.Windows.Input;
 
 using ICSharpCode.Decompiler.IL;
+using ICSharpCode.ILSpy.Docking;
 
 using TomsToolbox.Wpf;
 
@@ -31,6 +32,8 @@ namespace ICSharpCode.ILSpy.ViewModels
 	{
 		private Throttle titleChangeThrottle;
 
+		public static DockWorkspace DockWorkspace => App.ExportProvider.GetExportedValue<DockWorkspace>();
+
 		protected PaneModel()
 		{
 			titleChangeThrottle = new Throttle(() => OnPropertyChanged(nameof(Title)));
@@ -63,7 +66,7 @@ namespace ICSharpCode.ILSpy.ViewModels
 
 			public void Execute(object parameter)
 			{
-				Docking.DockWorkspace.Instance.Remove(model);
+				DockWorkspace.Remove(model);
 			}
 		}
 

ILSpy/Views/DebugSteps.xaml.cs

@@ -22,6 +22,7 @@ namespace ICSharpCode.ILSpy
 		private readonly AssemblyTreeModel assemblyTreeModel;
 		private readonly SettingsService settingsService;
 		private readonly LanguageService languageService;
+		private readonly DockWorkspace dockWorkspace;
 
 		static readonly ILAstWritingOptions writingOptions = new ILAstWritingOptions {
 			UseFieldSugar = true,
@@ -33,12 +34,13 @@ namespace ICSharpCode.ILSpy
 #if DEBUG
 		ILAstLanguage language;
 #endif
-		public DebugSteps(AssemblyTreeModel assemblyTreeModel, SettingsService settingsService, LanguageService languageService)
+		public DebugSteps(AssemblyTreeModel assemblyTreeModel, SettingsService settingsService, LanguageService languageService, DockWorkspace dockWorkspace)
 		{
 			this.assemblyTreeModel = assemblyTreeModel;
 			this.settingsService = settingsService;
 			this.languageService = languageService;
-			
+			this.dockWorkspace = dockWorkspace;
+
 			InitializeComponent();
 
 #if DEBUG
@@ -132,8 +134,8 @@ namespace ICSharpCode.ILSpy
 		void DecompileAsync(int step, bool isDebug = false)
 		{
 			lastSelectedStep = step;
-			var state = DockWorkspace.Instance.ActiveTabPage.GetState();
-			DockWorkspace.Instance.ActiveTabPage.ShowTextViewAsync(textView => textView.DecompileAsync(assemblyTreeModel.CurrentLanguage, assemblyTreeModel.SelectedNodes,
+			var state = dockWorkspace.ActiveTabPage.GetState();
+			dockWorkspace.ActiveTabPage.ShowTextViewAsync(textView => textView.DecompileAsync(assemblyTreeModel.CurrentLanguage, assemblyTreeModel.SelectedNodes,
 				new DecompilationOptions(assemblyTreeModel.CurrentLanguageVersion, settingsService.DecompilerSettings, settingsService.DisplaySettings) {
 					StepLimit = step,
 					IsDebug = isDebug,