DP44/enriched-qwen3-coder-next/DataPRO/Modules/SystemSettings/Tables/ViewModel.md

source_files, generated_at, model, schema_version, sha256

source_files	generated_at	model	schema_version	sha256
DataPRO/Modules/SystemSettings/Tables/ViewModel/TablesSettingsViewModel.cs	2026-04-16T04:40:21.830816+00:00	Qwen/Qwen3-Coder-Next-FP8	1	d6165d55cd0ea9cd

ViewModel

Documentation: TablesSettingsViewModel

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1. Purpose

TablesSettingsViewModel is the view model for the Tables Settings module within the application’s UI layer. It acts as the data context for ITablesSettingsView, coordinating UI state (e.g., busy status, menu/navigation visibility) and bridging communication between the view and the application’s event infrastructure via IEventAggregator. It also exposes InteractionRequests to support modal notifications and confirmations through Prism’s interaction patterns. This module is part of a modular, MEF-exported component system and is intended to be shared across the application lifecycle.

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2. Public Interface

Class: TablesSettingsViewModel

• Exported as: [Export(typeof(ITablesSettingsView))] — implies it is intended to be resolved as an ITablesSettingsView (likely via MEF or Unity).
• Creation Policy: Shared — only one instance exists per application lifetime.

Properties

Property	Type	Description
View	ITablesSettingsView	Reference to the associated view; set in constructor.
NotificationRequest	InteractionRequest<Notification>	Used to trigger display of notification popups (e.g., informational messages).
ConfirmationRequest	InteractionRequest<Confirmation>	Used to trigger confirmation dialogs.
IsDirty	bool	Read-only; currently always false (no logic implemented to set it).
IsBusy	bool	Gets/sets busy state; raises PropertyChanged on change.
IsMenuIncluded	bool	Gets/sets whether the menu is included in the view; raises PropertyChanged.
IsNavigationIncluded	bool	Gets/sets whether navigation is included in the view; raises PropertyChanged.
HeaderInfo	string	Read-only; always returns "MainRegion".

Methods

Method	Signature	Description
Cleanup	void Cleanup()	No-op stub.
CleanupAsync	Task CleanupAsync()	Returns Task.CompletedTask.
Initialize	void Initialize()	No-op stub.
Initialize	void Initialize(object parameter)	No-op stub.
Initialize	void Initialize(object parameter, object model)	No-op stub.
InitializeAsync	Task InitializeAsync()	Returns Task.CompletedTask.
InitializeAsync	Task InitializeAsync(object parameter)	Returns Task.CompletedTask.
Activated	void Activated()	No-op stub.

Event Handlers (Private)

Method	Signature	Description
OnBusyIndicatorNotification	private void OnBusyIndicatorNotification(bool eventArg)	Sets IsBusy to eventArg.
OnRaiseNotification	private void OnRaiseNotification(NotificationContentEventArgs eventArgsWithTitle)	Transforms NotificationContentEventArgs (with title/message/image) into a Notification object and raises NotificationRequest. Note: it discards the Title and Image fields of the original event args and passes them via NotificationContentEventArgs constructor with empty strings for some parameters — see Gotchas.

Interface Implementations

Interface	Method	Signature	Description
INotifyPropertyChanged	PropertyChanged	event PropertyChangedEventHandler PropertyChanged	Raised via OnPropertyChanged.
IBasePropertyChanged	OnPropertyChanged	void IBasePropertyChanged.OnPropertyChanged(string propertyName)	Delegates to OnPropertyChanged(propertyName).
—	SetProperty	bool SetProperty<T>(ref T storage, T value, string propertyName = null)	Throws NotImplementedException — not implemented.

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3. Invariants

• View.DataContext is always set to this (the view model) in the constructor.
• IsBusy is initialized to false and only modified via OnBusyIndicatorNotification, which is subscribed to BusyIndicatorChangeNotification.
• NotificationRequest and ConfirmationRequest are initialized in the constructor and never reassigned.
• HeaderInfo is a constant string "MainRegion" and never changes.
• IsDirty is declared but never set — its value remains false for the lifetime of the instance.
• SetProperty is declared but unimplemented — calling it will always throw NotImplementedException.

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4. Dependencies

Imports / Dependencies (via constructor parameters and using directives)

• Prism Libraries:
  • IEventAggregator — for pub/sub event handling.
  • IRegionManager — for region navigation (though unused in current implementation).
  • Unity container (IUnityContainer) — for dependency injection.
• Custom Infrastructure:
  • DTS.Common.Events.RaiseNotification — event type subscribed to in constructor.
  • DTS.Common.Events.BusyIndicatorChangeNotification — event type subscribed to in constructor.
  • DTS.Common.Base.IBasePropertyChanged — interface implemented explicitly.
  • DTS.Common.Interface.ITablesSettingsView — view interface.
• MEF:
  • [Export(typeof(ITablesSettingsView))] — indicates this type is registered as an export for ITablesSettingsView.
• UI Framework:
  • Prism.Regions, Prism.Events, Prism.Interactivity — used for region management, event aggregation, and interaction requests.

Depended Upon By

• The view (ITablesSettingsView) — this view model is bound to its DataContext.
• Likely consumed via MEF/Unity resolution as ITablesSettingsView.
• Other modules may publish RaiseNotification or BusyIndicatorChangeNotification events to trigger UI feedback via this view model.

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5. Gotchas

• SetProperty is unimplemented — throws NotImplementedException. This breaks expected MVVM patterns (e.g., INotifyPropertyChanged helpers). Developers should avoid calling it.
• NotificationContentEventArgs transformation in OnRaiseNotification is lossy:
  The method constructs a new NotificationContentEventArgs with empty strings for the 2nd and 4th parameters (likely OkContent and CancelContent), discarding any original values. This may cause unexpected behavior if callers expect those fields to be preserved.
• No-op lifecycle methods: Initialize, InitializeAsync, Activated, Cleanup, and CleanupAsync contain no logic — may indicate incomplete implementation or deferred functionality.
• IsDirty is never set: Despite being a public property, it is never assigned — always false. This may mislead consumers expecting dirty-state tracking.
• HeaderInfo is hardcoded: Always returns "MainRegion" — no dynamic behavior or configuration.
• IBasePropertyChanged.OnPropertyChanged is implemented explicitly — only callable via interface cast.
• Thread context for BusyIndicatorChangeNotification: Subscribed with ThreadOption.PublisherThread, meaning the handler runs on the publisher’s thread — may require dispatcher marshaling if the publisher is not on the UI thread (though IsBusy setter calls OnPropertyChanged, which should marshal to UI thread if INotifyPropertyChanged is handled by Prism’s binding system).

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Documentation generated from source file TablesSettingsViewModel.cs only. No external behavior or assumptions beyond what is visible in the source.