DP44/enriched-partialglm/DTS Viewer/DTS.Viewer/ViewModel.md

source_files, generated_at, model, schema_version, sha256

source_files	generated_at	model	schema_version	sha256
DTS Viewer/DTS.Viewer/ViewModel/NavigationViewModel.cs DTS Viewer/DTS.Viewer/ViewModel/MenuViewModel.cs DTS Viewer/DTS.Viewer/ViewModel/ShellViewModel.cs DTS Viewer/DTS.Viewer/ViewModel/ViewerShellViewModel.cs DTS Viewer/DTS.Viewer/ViewModel/MainViewModel.cs	2026-04-16T11:23:08.528119+00:00	zai-org/GLM-5-FP8	1	7a17d7bd36c83744

DTS.Viewer ViewModel Documentation

1. Purpose

This module contains the core ViewModel layer for the DTS Viewer WPF application, implementing the MVVM pattern using Microsoft Prism and Unity. It provides the orchestration layer between the Views and the business logic, managing navigation regions, user notifications, and shell composition. The ViewModels handle view lifecycle (initialization, activation, cleanup), region management for dynamic view injection, and event-driven communication via IEventAggregator. This module serves as the structural backbone for the application's UI composition system.

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2. Public Interface

NavigationViewModel

Inherits: BaseViewModel<INavigationViewModel>
Implements: INavigationViewModel

Member	Signature	Description
Constructor	NavigationViewModel(INavigationView view, IRegionManager regionManager, IEventAggregator eventAggregator, IUnityContainer unityContainer)	Initializes the view model, sets DataContext, creates interaction requests, and subscribes to RaiseNotification event.
NavigationView	INavigationView { get; private set; }	Holds reference to the associated view.
ContextNavigationRegion	object { get; set; }	Gets/sets the content of the NavigationRegion on the view. Raises OnPropertyChanged("ContextNavigationRegion") on set.
HeaderInfo	string { get; }	Returns hardcoded string "NavigationRegion".
Initialize	override void Initialize()	Empty implementation.
Initialize	override void Initialize(object parameter)	Casts parameter to IShellViewModel and assigns to Parent.
OnRaiseNotification	void OnRaiseNotification(NotificationContentEventArgs eventArgsWithTitle)	Handles RaiseNotification events, transforms args and raises NotificationRequest.
IsBusy	bool { get; set; }	Throws NotImplementedException.
IsDirty	bool { get; }	Throws NotImplementedException.
Activated	override void Activated()	Throws NotImplementedException.
Cleanup	override void Cleanup()	Throws NotImplementedException.
CleanupAsync	Task CleanupAsync()	Throws NotImplementedException.
InitializeAsync	override Task InitializeAsync()	Throws NotImplementedException.
InitializeAsync	override Task InitializeAsync(object parameter)	Throws NotImplementedException.

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MenuViewModel

Inherits: BaseViewModel<IMenuViewModel>
Implements: IMenuViewModel

Member	Signature	Description
Constructor	MenuViewModel(IMenuView view, IRegionManager regionManager, IEventAggregator eventAggregator, IUnityContainer unityContainer)	Initializes the view model, sets DataContext, creates interaction requests, and subscribes to RaiseNotification event.
View	IMenuView { get; private set; }	Holds reference to the associated view.
HeaderInfo	string { get; }	Returns hardcoded string "MainRegion".
Initialize	override void Initialize()	Contains placeholder code (int i = 10;).
Initialize	override void Initialize(object parameter)	Casts parameter to IShellViewModel and assigns to Parent.
CreateViews	void CreateViews(Boolean initialize)	Creates a ViewDefinition for RegionNames.MainRegion with IBaseView/IBaseViewModel types. Currently the _regionManager.AddView call is commented out.
OnRaiseNotification	void OnRaiseNotification(NotificationContentEventArgs eventArgsWithTitle)	Handles RaiseNotification events.
IsBusy	bool { get; set; }	Throws NotImplementedException.
IsDirty	bool { get; }	Throws NotImplementedException.
Activated	override void Activated()	Throws NotImplementedException.
Cleanup	override void Cleanup()	Throws NotImplementedException.
CleanupAsync	Task CleanupAsync()	Throws NotImplementedException.
InitializeAsync	override Task InitializeAsync()	Throws NotImplementedException.
InitializeAsync	override Task InitializeAsync(object parameter)	Throws NotImplementedException.

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ShellViewModel

Inherits: NotificationObject
Implements: IViewerShellViewModel
Attributes: [Export(typeof(IShellView))], [PartCreationPolicy(CreationPolicy.Shared)]

Member	Signature	Description
Constructor	ShellViewModel(IViewerShellView view, IRegionManager regionManager, IEventAggregator eventAggregator, IUnityContainer unityContainer)	Initializes view, subscribes to RaiseNotification, registers IMainView→MainView and IMainViewModel→MainViewModel (singleton) with Unity.
View	IViewerShellView { get; private set; }	Holds reference to the shell view.
ContextMainRegion	Object { get; set; }	Gets/sets content of MainRegion from ShellView. Raises OnPropertyChanged("ContextMainRegion") on set.
IsMenuIncluded	bool { get; set; }	Controls menu visibility. Raises OnPropertyChanged on set.
IsNavigationIncluded	bool { get; set; }	Controls navigation visibility. Raises OnPropertyChanged on set.
HeaderInfo	string { get; }	Returns hardcoded string "MainRegion".
GetRegions	List<FrameworkElement> GetRegions()	Uses Utils.GetChildrenByName to find elements named "Region" in MainShell.
Initialize	void Initialize()	Placeholder implementation (int i = 10;).
Initialize	void Initialize(object parameter)	Placeholder implementation (int i = 22;).
Initialize	void Initialize(object parameter, object model)	Empty implementation.
Activated	void Activated()	Placeholder (var s = String.Empty;).
OnRaiseNotification	void OnRaiseNotification(NotificationContentEventArgs eventArgsWithTitle)	Handles RaiseNotification events.
IsBusy	bool { get; }	Throws NotImplementedException.
IsDirty	bool { get; }	Throws NotImplementedException.
Cleanup	void Cleanup()	Throws NotImplementedException.
CleanupAsync	Task CleanupAsync()	Throws NotImplementedException.
InitializeAsync	Task InitializeAsync()	Throws NotImplementedException.
InitializeAsync	Task InitializeAsync(object parameter)	Throws NotImplementedException.

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ViewerShellViewModel

Inherits: NotificationObject
Implements: IViewerShellViewModel
Attributes: [Export(typeof(IShellView))], [PartCreationPolicy(CreationPolicy.Shared)]

Member	Signature	Description
Constructor	ViewerShellViewModel(IViewerShellView view, IRegionManager regionManager, IEventAggregator eventAggregator, IUnityContainer unityContainer)	Initializes view, subscribes to RaiseNotification, registers IViewerMainView→ViewerMainView and IViewerMainViewModel→ViewerMainViewModel (singleton) with Unity.
View	IViewerShellView { get; private set; }	Holds reference to the shell view.
ContextMainRegion	Object { get; set; }	Gets/sets content of MainRegion from ViewerShellView.
IsMenuIncluded	bool { get; set; }	Controls menu visibility.
IsNavigationIncluded	bool { get; set; }	Controls navigation visibility.
IsBusy	bool { get; set; }	Implemented - unlike other ViewModels, this has a backing field _isBusy and raises property changed.
HeaderInfo	string { get; }	Returns hardcoded string "MainRegion".
GetRegions	List<FrameworkElement> GetRegions()	Uses Utils.GetChildrenByName on ViewerShellView.MainShell.
Initialize	void Initialize()	Placeholder (int i = 10;).
Initialize	void Initialize(object parameter)	Placeholder (int i = 22;).
Initialize	void Initialize(object parameter, object model)	Empty implementation.
Activated	void Activated()	Placeholder (var s = String.Empty;).
OnRaiseNotification	void OnRaiseNotification(NotificationContentEventArgs eventArgsWithTitle)	Handles RaiseNotification events.
IsDirty	bool { get; }	Throws NotImplementedException.
Cleanup	void Cleanup()	Throws NotImplementedException.
CleanupAsync	Task CleanupAsync()	Throws NotImplementedException.
InitializeAsync	Task InitializeAsync()	Throws NotImplementedException.
InitializeAsync	Task InitializeAsync(object parameter)	Throws NotImplementedException.
OnPropertyChanged	void IBasePropertyChanged.OnPropertyChanged(string propertyName)	Throws NotImplementedException.

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MainViewModel

Inherits: BaseViewModel<IMainViewModel>
Implements: IMainViewModel

Member	Signature	Description
Constructor	MainViewModel(IMainView view, IRegionManager regionManager, IEventAggregator eventAggregator, IUnityContainer unityContainer)	Initializes view, subscribes to RaiseNotification and AssemblyListNotification events, registers IMenuView/IMenuViewModel and INavigationView/INavigationViewModel with Unity.
View	IMainView { get; private set; }	Holds reference to the main view.
ContextMainRegion	object { get; set; }	Currently returns null on get; setter raises OnPropertyChanged("ContextMainRegion") but content assignment is commented out.
IsMenuIncluded	bool { get; set; }	Backed by _isMenuIncluded field.
IsNavigationIncluded	bool { get; set; }	Backed by _isNavigationIncluded field.
HeaderInfo	string { get; }	Returns hardcoded string "MainRegion".
Initialize	override void Initialize()	Empty implementation.
Initialize	override void Initialize(object parameter)	Casts to IViewerShellViewModel, sets Parent.IsMenuIncluded and Parent.IsNavigationIncluded, subscribes to AssemblyListNotification event with ThreadOption.PublisherThread.
Activated	override void Activated()	Empty implementation.
OnAssemblyListChange	void OnAssemblyListChange(AssemblyListInfo e)	Handler for AssemblyListNotification event. Entire implementation is commented out.
OnRaiseNotification	void OnRaiseNotification(NotificationContentEventArgs eventArgsWithTitle)	Handles RaiseNotification events.

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3. Invariants

1. Constructor Pattern: All ViewModels must receive exactly four constructor parameters: the view interface, IRegionManager, IEventAggregator, and IUnityContainer. The view's DataContext is set to this within the constructor.

2. Event Subscription: All ViewModels subscribe to RaiseNotification event via EventAggregator.GetEvent<RaiseNotification>().Subscribe(OnRaiseNotification) during construction.

3. Notification Transformation: The OnRaiseNotification handler always transforms NotificationContentEventArgs to a new instance with (Message, MessageDetails, Image) before raising the NotificationRequest.

4. Parent Assignment: The Initialize(object parameter) method expects parameter to be castable to either IShellViewModel (for NavigationViewModel, MenuViewModel) or IViewerShellViewModel (for MainViewModel).

5. Region Naming Convention: Region content properties follow the naming pattern Context{RegionName}Region (e.g., ContextMainRegion, ContextNavigationRegion).

6. HeaderInfo Consistency: All ViewModels return a hardcoded region name string from HeaderInfo.

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4. Dependencies

External Dependencies (Imports)

• Microsoft.Practices.Prism.Events - IEventAggregator, event publishing/subscription
• Microsoft.Practices.Prism.Interactivity.InteractionRequest - InteractionRequest<T>, Notification, Confirmation
• Microsoft.Practices.Prism.Regions - IRegionManager
• Microsoft.Practices.Prism.ViewModel - NotificationObject
• Microsoft.Practices.Unity - IUnityContainer, ContainerControlledLifetimeManager
• System.ComponentModel.Composition - MEF attributes (Export, PartCreationPolicy, CreationPolicy)
• System.Windows - FrameworkElement (used in GetRegions())

Internal Dependencies (DTS.*)

• DTS.Common.Base - BaseViewModel<T>, ViewDefinition
• DTS.Common.Events - RaiseNotification, NotificationContentEventArgs, AssemblyListNotification, AssemblyListInfo
• DTS.Common.Interface - INavigationViewModel, IMenuViewModel, IShellViewModel, IViewerShellViewModel, IMainViewModel, IBaseViewModel, IBaseView, IBasePropertyChanged
• DTS.Common.Utils - Utils.GetChildrenByName
• DTS.Common.Classes - Referenced in MenuViewModel
• DTS.Viewer.View - ShellView, ViewerShellView, MainView, MenuView, NavigationView, ViewerMainView

Dependency Graph

ShellViewModel / ViewerShellViewModel (root)
    └── registers MainViewModel / ViewerMainViewModel
            └── MainViewModel
                    └── registers MenuViewModel, NavigationViewModel

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5. Gotchas

1. Stale XML Documentation: The XML comment in NavigationViewModel constructor references "TechnologyDoFrontEditViewModel" which does not match the actual class name. Similarly, MenuViewModel references "TechnologyDomainEditViewModel". These appear to be copy-paste artifacts from another codebase.

2. Widespread NotImplementedException: The majority of lifecycle methods (Activated, Cleanup, CleanupAsync, InitializeAsync, IsDirty getter) throw NotImplementedException across all ViewModels. This indicates incomplete implementation—callers must not rely on these methods.

3. Inconsistent IsBusy Implementation:

   • ShellViewModel.IsBusy throws NotImplementedException
   • ViewerShellViewModel.IsBusy is fully implemented with backing field
   • NavigationViewModel.IsBusy and MenuViewModel.IsBusy throw NotImplementedException

   This inconsistency suggests ViewerShellViewModel is more complete than ShellViewModel.

4. Commented-Out Critical Logic:

   • MainViewModel.OnAssemblyListChange() is entirely commented out—the method receives AssemblyListInfo but does nothing with it.
   • MainViewModel.ContextMainRegion getter returns null and setter logic is commented out.
   • MenuViewModel.CreateViews() has _regionManager.AddView call commented out.

5. new Keyword Hiding: Several members use new to hide base class members:

   • NavigationViewModel: PropertyChanged event, OnPropertyChanged method, IsBusy, IsDirty, CleanupAsync
   • MenuViewModel: IsBusy, IsDirty, CleanupAsync
   • MainViewModel: IsMenuIncluded, IsNavigationIncluded

   This may cause unexpected behavior when casting to base types.

6. Placeholder Code: Multiple Initialize methods contain placeholder statements like int i = 10; or var s = String.Empty; that serve no functional purpose—likely debug artifacts.

7. Duplicate Shell Implementations: Both ShellViewModel and ViewerShellViewModel implement IViewerShellViewModel and have nearly identical structure. The relationship between these two classes is unclear from source alone—they may represent different shell configurations or be a refactoring in progress.

8. ThreadOption.PublisherThread in Event Subscription: `