DP44/enriched-qwen3-coder-next/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	2026-04-16T14:00:47.869288+00:00	zai-org/GLM-5-FP8	1	7a17d7bd36c83744

DTS Viewer ViewModels Documentation

1. Purpose

This module contains the core ViewModel layer for the DTS Viewer WPF application, implementing the MVVM pattern with Prism framework support. It provides the orchestration layer between Views and business logic, managing UI state, region navigation, and inter-component communication via event aggregation. The ViewModels handle shell composition, menu/navigation regions, and main content presentation through Unity dependency injection and Prism's region management system.

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2. Public Interface

NavigationViewModel

Signature: public class NavigationViewModel : BaseViewModel<INavigationViewModel>, 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	public INavigationView NavigationView { get; private set; }	Gets the associated navigation view instance
NotificationRequest	public InteractionRequest<Notification> NotificationRequest { get; private set; }	Interaction request for displaying notifications
ConfirmationRequest	public InteractionRequest<Confirmation> ConfirmationRequest { get; private set; }	Interaction request for displaying confirmations
Initialize	public override void Initialize()	Empty implementation
Initialize	public override void Initialize(object parameter)	Casts parameter to IShellViewModel and assigns to Parent
ContextNavigationRegion	public object ContextNavigationRegion { get; set; }	Gets/sets content of NavigationRegion on the NavigationView
HeaderInfo	public string HeaderInfo { get; }	Returns "NavigationRegion"
IsBusy	public new bool IsBusy { get; set; }	Throws NotImplementedException
Activated	public override void Activated()	Throws NotImplementedException
IsDirty	public new bool IsDirty { get; }	Throws NotImplementedException
Cleanup	public override void Cleanup()	Throws NotImplementedException
CleanupAsync	public new Task CleanupAsync()	Throws NotImplementedException
InitializeAsync	public override Task InitializeAsync()	Throws NotImplementedException
InitializeAsync	public override Task InitializeAsync(object parameter)	Throws NotImplementedException

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MenuViewModel

Signature: public class MenuViewModel : BaseViewModel<IMenuViewModel>, 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	public IMenuView View { get; private set; }	Gets the associated menu view instance
NotificationRequest	public InteractionRequest<Notification> NotificationRequest { get; private set; }	Interaction request for displaying notifications
ConfirmationRequest	public InteractionRequest<Confirmation> ConfirmationRequest { get; private set; }	Interaction request for displaying confirmations
Initialize	public override void Initialize()	Contains placeholder code (int i = 10;)
Initialize	public override void Initialize(object parameter)	Casts parameter to IShellViewModel and assigns to Parent
CreateViews	private void CreateViews(Boolean initialize)	Creates a ViewDefinition for RegionNames.MainRegion with IBaseView/IBaseViewModel types (regionManager.AddView call is commented out)
HeaderInfo	public string HeaderInfo { get; }	Returns "MainRegion"
IsBusy	public new bool IsBusy { get; set; }	Throws NotImplementedException
Activated	public override void Activated()	Throws NotImplementedException
IsDirty	public new bool IsDirty { get; }	Throws NotImplementedException
Cleanup	public override void Cleanup()	Throws NotImplementedException
CleanupAsync	public new Task CleanupAsync()	Throws NotImplementedException
InitializeAsync	public override Task InitializeAsync()	Throws NotImplementedException
InitializeAsync	public override Task InitializeAsync(object parameter)	Throws NotImplementedException

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ShellViewModel

Signature: public class ShellViewModel : NotificationObject, IViewerShellViewModel

Member	Signature	Description
Attributes	[Export(typeof(IShellView))], [PartCreationPolicy(CreationPolicy.Shared)]	MEF export attributes for shared shell view
Constructor	ShellViewModel(IViewerShellView view, IRegionManager regionManager, IEventAggregator eventAggregator, IUnityContainer unityContainer)	Initializes view model, subscribes to RaiseNotification, registers IMainView/MainView and IMainViewModel/MainViewModel (singleton) in Unity container
View	public IViewerShellView View { get; private set; }	Gets the associated shell view instance
NotificationRequest	public InteractionRequest<Notification> NotificationRequest { get; private set; }	Interaction request for displaying notifications
ConfirmationRequest	public InteractionRequest<Confirmation> ConfirmationRequest { get; private set; }	Interaction request for displaying confirmations
Initialize	public void Initialize()	Contains placeholder code (int i = 10;)
Initialize	public void Initialize(object parameter)	Contains placeholder code (int i = 22;)
Initialize	public void Initialize(object parameter, object model)	Empty implementation
Activated	public void Activated()	Sets empty string variable
GetRegions	public List<FrameworkElement> GetRegions()	Uses Utils.GetChildrenByName to find elements named "Region" in MainShell
ContextMainRegion	public Object ContextMainRegion { get; set; }	Gets/sets content of MainRegion on the ShellView
IsMenuIncluded	public bool IsMenuIncluded { get; set; }	Gets/sets whether menu is included; raises PropertyChanged
IsNavigationIncluded	public bool IsNavigationIncluded { get; set; }	Gets/sets whether navigation is included; raises PropertyChanged
HeaderInfo	public string HeaderInfo { get; }	Returns "MainRegion"
IsBusy	public bool IsBusy { get; }	Throws NotImplementedException (getter only)
IsDirty	public bool IsDirty { get; }	Throws NotImplementedException
Cleanup	public void Cleanup()	Throws NotImplementedException
CleanupAsync	public Task CleanupAsync()	Throws NotImplementedException
InitializeAsync	public Task InitializeAsync()	Throws NotImplementedException
InitializeAsync	public Task InitializeAsync(object parameter)	Throws NotImplementedException

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ViewerShellViewModel

Signature: public class ViewerShellViewModel : NotificationObject, IViewerShellViewModel

Member	Signature	Description
Attributes	[Export(typeof(IShellView))], [PartCreationPolicy(CreationPolicy.Shared)]	MEF export attributes for shared shell view
Constructor	ViewerShellViewModel(IViewerShellView view, IRegionManager regionManager, IEventAggregator eventAggregator, IUnityContainer unityContainer)	Initializes view model, subscribes to RaiseNotification, registers IViewerMainView/ViewerMainView and IViewerMainViewModel/ViewerMainViewModel (singleton) in Unity container
View	public IViewerShellView View { get; private set; }	Gets the associated viewer shell view instance
NotificationRequest	public InteractionRequest<Notification> NotificationRequest { get; private set; }	Interaction request for displaying notifications
ConfirmationRequest	public InteractionRequest<Confirmation> ConfirmationRequest { get; private set; }	Interaction request for displaying confirmations
Initialize	public void Initialize()	Contains placeholder code (int i = 10;)
Initialize	public void Initialize(object parameter)	Contains placeholder code (int i = 22;)
Initialize	public void Initialize(object parameter, object model)	Empty implementation
Activated	public void Activated()	Sets empty string variable
GetRegions	public List<FrameworkElement> GetRegions()	Uses Utils.GetChildrenByName to find elements named "Region" in MainShell
ContextMainRegion	public Object ContextMainRegion { get; set; }	Gets/sets content of MainRegion on the ViewerShellView
IsMenuIncluded	public bool IsMenuIncluded { get; set; }	Gets/sets whether menu is included; raises PropertyChanged
IsNavigationIncluded	public bool IsNavigationIncluded { get; set; }	Gets/sets whether navigation is included; raises PropertyChanged
IsBusy	public bool IsBusy { get; set; }	Implemented - Gets/sets busy state with PropertyChanged notification
HeaderInfo	public string HeaderInfo { get; }	Returns "MainRegion"
IsDirty	public bool IsDirty { get; }	Throws NotImplementedException
Cleanup	public void Cleanup()	Throws NotImplementedException
CleanupAsync	public Task CleanupAsync()	Throws NotImplementedException
InitializeAsync	public Task InitializeAsync()	Throws NotImplementedException
InitializeAsync	public Task InitializeAsync(object parameter)	Throws NotImplementedException
OnPropertyChanged	void IBasePropertyChanged.OnPropertyChanged(string propertyName)	Throws NotImplementedException

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MainViewModel

Signature: public class MainViewModel : BaseViewModel<IMainViewModel>, IMainViewModel

Member	Signature	Description
Constructor	MainViewModel(IMainView view, IRegionManager regionManager, IEventAggregator eventAggregator, IUnityContainer unityContainer)	Initializes view model, subscribes to RaiseNotification and AssemblyListNotification events, registers IMenuView/MenuView, IMenuViewModel/MenuViewModel, INavigationView/NavigationView, INavigationViewModel/NavigationViewModel in Unity container
View	public IMainView View { get; private set; }	Gets the associated main view instance
NotificationRequest	public InteractionRequest<Notification> NotificationRequest { get; private set; }	Interaction request for displaying notifications
ConfirmationRequest	public InteractionRequest<Confirmation> ConfirmationRequest { get; private set; }	Interaction request for displaying confirmations
Initialize	public override void Initialize()	Empty implementation
Initialize	public override void Initialize(object parameter)	Casts parameter to IViewerShellViewModel, sets Parent.IsMenuIncluded and Parent.IsNavigationIncluded, subscribes to AssemblyListNotification event
Activated	public override void Activated()	Empty implementation
OnAssemblyListChange	private void OnAssemblyListChange(AssemblyListInfo e)	Handler for assembly list changes - entire implementation is commented out
ContextMainRegion	public object ContextMainRegion { get; set; }	Getter returns null; setter has commented-out implementation
IsMenuIncluded	public new bool IsMenuIncluded { get; set; }	Gets/sets menu inclusion flag with PropertyChanged notification
IsNavigationIncluded	public new bool IsNavigationIncluded { get; set; }	Gets/sets navigation inclusion flag with PropertyChanged notification
HeaderInfo	public string HeaderInfo { get; }	Returns "MainRegion"

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3. Invariants

1. Constructor Initialization Order: All ViewModels must set View.DataContext = this before any other initialization in constructors.
2. Event Subscription Pattern: All ViewModels subscribe to RaiseNotification event via EventAggregator.GetEvent<RaiseNotification>().Subscribe(OnRaiseNotification) in their constructors.
3. Notification Transformation: OnRaiseNotification handlers always transform NotificationContentEventArgs to a new instance with (Message, MessageDetails, Image) constructor before raising the notification.
4. Parent Type Casting: Initialize(object parameter) implementations cast the parameter to specific interface types (IShellViewModel or IViewerShellViewModel) without null checks.
5. Region Content Access: ContextMainRegion and ContextNavigationRegion properties cast their View to the concrete type (e.g., ((ShellView)View)) to access region content.
6. MEF Registration: ShellViewModel and ViewerShellViewModel are both exported as IShellView with CreationPolicy.Shared.
7. Unity Registration Pattern: View/ViewModel pairs are registered together in constructors (e.g., RegisterType<IMainView, MainView>() followed by RegisterType<IMainViewModel, MainViewModel>()).

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4. Dependencies

External Dependencies (Imports)

Namespace	Purpose
Microsoft.Practices.Prism.Events	Event aggregation (IEventAggregator, pub/sub pattern)
Microsoft.Practices.Prism.Interactivity.InteractionRequest	InteractionRequest<T>, Notification, Confirmation for UI dialogs
Microsoft.Practices.Prism.Regions	IRegionManager for region-based navigation
Microsoft.Practices.Prism.ViewModel	NotificationObject base class
Microsoft.Practices.Unity	IUnityContainer for dependency injection
System.ComponentModel.Composition	MEF attributes (Export, PartCreationPolicy)
System.Windows	FrameworkElement for UI element handling

Internal Dependencies

Namespace	Purpose
DTS.Common.Base	BaseViewModel<T>, IBaseViewModel, IBasePropertyChanged
DTS.Common.Events	RaiseNotification, NotificationContentEventArgs, AssemblyListNotification, AssemblyListInfo
DTS.Common.Interface	INavigationView, IMenuView, IMainView, IViewerShellView, IShellViewModel, IViewerShellViewModel, IMainViewModel, IMenuViewModel, INavigationViewModel, IBaseView, IBaseViewModel
DTS.Common.Classes	ViewDefinition
DTS.Common	RegionNames (contains MainRegion constant)
DTS.Common.Utils	Utils.GetChildrenByName static method
DTS.Viewer.View	Concrete view types: ShellView, ViewerShellView, MainView, MenuView, NavigationView, ViewerMainView

Dependency Graph (ViewModel → registers)

• ShellViewModel → registers MainView/MainViewModel
• ViewerShellViewModel → registers ViewerMainView/ViewerMainViewModel
• MainViewModel → registers MenuView/MenuViewModel, NavigationView/NavigationViewModel

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5. Gotchas

1. Duplicate MEF Exports: Both ShellViewModel and ViewerShellViewModel are exported as IShellView with CreationPolicy.Shared. This could cause resolution conflicts when importing IShellView.

2. NotImplementedException Landmines: Multiple critical lifecycle methods throw NotImplementedException:

   • Cleanup(), CleanupAsync(), InitializeAsync() in all ViewModels
   • IsBusy getter/setter in NavigationViewModel, MenuViewModel, ShellViewModel
   • IsDirty getter in all ViewModels
   • Activated() in NavigationViewModel and MenuViewModel Calling these will crash the application.

3. new Keyword Hiding: Several properties use new keyword to hide base class members (IsBusy, IsDirty, IsMenuIncluded, IsNavigationIncluded, OnPropertyChanged, PropertyChanged event). This can lead to unexpected behavior when casting to base types.

4. Commented-Out Implementation: MainViewModel.OnAssemblyListChange and MainViewModel.ContextMainRegion setter have substantial commented-out code, suggesting incomplete feature implementation. The ContextMainRegion getter always returns null.

5. Placeholder Code: Several Initialize() methods contain no-op code