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

source_files, generated_at, model, schema_version, sha256

source_files	generated_at	model	schema_version	sha256
DTS Viewer/DTS.Viewer.Modules/DTS.Viewer.ChartOptions/ViewModel/ChartOptionsViewModel.cs	2026-04-16T11:18:03.613000+00:00	zai-org/GLM-5-FP8	1	7f2f2e90f6f17587

Documentation: ChartOptionsViewModel

1. Purpose

ChartOptionsViewModel is a Prism-based view model that manages user-configurable chart display options within the DTS Viewer application. It serves as an intermediary between chart option UI controls and the underlying chart rendering system, handling unit type selection (EU, mV, ADC), axis range configuration, cursor visibility, and PDF export functionality. The module supports multiple parent contexts including IViewerMainViewModel and IPSDReportMainViewModel, with different default configurations based on the parent type.

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2. Public Interface

Constructor

public ChartOptionsViewModel(
    IChartOptionsView view, 
    IRegionManager regionManager, 
    IEventAggregator eventAggregator, 
    IUnityContainer unityContainer)

Initializes the view model, sets up the view's DataContext, creates interaction requests, and subscribes to ChartAxisChangedEvent.

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Properties

Property	Type	Access	Description
Parent	IBaseViewModel	get/set	Reference to the parent view model; used for event filtering.
NotificationRequest	InteractionRequest<Notification>	get	Prism interaction request for notifications.
ConfirmationRequest	InteractionRequest<Confirmation>	get	Prism interaction request for confirmations.
View	IBaseView	get/set	The associated view interface.
Model	IChartOptionsModel	get/set	The chart options model; resolves from container on set. Raises OnPropertyChanged("Model").
ContextSearchRegion	object	get/set	Unused in visible code.
IsMenuIncluded	bool	get/set	Hides base property.
IsNavigationIncluded	bool	get/set	Hides base property.
IsBusy	bool	get/set	Hides base property.
IsDirty	bool	get	Always returns default value; never assigned.
ChartOptionsVisability	bool	get/set	Controls visibility of chart options UI. Raises property changed notification.
ClearMarkersCommand	DelegateCommand	get	Lazy-initialized command that calls ClearMarkersMethod().

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Methods

public override void Initialize()

Empty override; performs no operations.

public override void Initialize(object parameter)

Initializes the view model with a parent context. Subscribes to events, resolves the model from Unity container, and configures defaults based on parameter type:

• If parameter is IViewerMainViewModel: Sets Model.DecimateData = true
• If parameter is Tuple<IBaseViewModel, string> where Item1 is IPSDReportMainViewModel: Configures based on chartType string ("Graph" vs other)

public void ShowMinMaxCursor(bool value)

Publishes CursorShowMinMaxChangedEvent with the given boolean value.

public void ResetZoomMethod()

Sets Model.YRange to YRangeScaleEnum.AutoRange and publishes ResetZoomChangedEvent with true.

public void ResetTMethod()

Publishes ResetZoomChangedEvent with false.

public void SaveToPDFMethod()

Publishes SaveToPDFRequestedEvent with the stored Directory path.

public void PublishChanges()

Publishes ChartOptionsChangedEvent with a ChartOptionsChangedEventArg containing ParentVM, Model, and ChartType.

public void ShowCusor(bool value)

Publishes CursorShowChangedEvent with the given boolean value.

public new void OnPropertyChanged(string propertyName)

Raises the PropertyChanged event for the specified property name.

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Events

public new event PropertyChangedEventHandler PropertyChanged

Hides the base class event; raised by OnPropertyChanged.

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3. Invariants

1. Model Resolution: Model must be resolved from IUnityContainer before use; it is not resolved in the constructor but in Initialize(object parameter).

2. Event Filtering: All received events are filtered by comparing args?.ParentVM to Parent. Events from other parent contexts are ignored.

3. Publish Guard Pattern: When programmatically modifying Model properties in response to events (e.g., in OnChartAxisChangedEvent), Model.CanPublishChanges must be set to false before modifications and restored to true afterward to prevent recursive event publishing.

4. Log Scale Constraint: When chartType == "Graph", Model.MinFixedY is set to 1e-12 because log scale cannot handle zero.

5. Unit Type Fallback: If channels do not support ADC or mV (determined by AllChannelsSupportADC / AllChannelsSupportmV), the Model.UnitType is automatically reset to ChartUnitTypeEnum.EU.

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4. Dependencies

This Module Depends On

Namespace	Types Used
DTS.Common.Base	BaseViewModel<T>, IBaseViewModel
DTS.Common.Enums.Viewer	ChartUnitTypeEnum, YRangeScaleEnum, FilterOptionEnum
DTS.Common.Enums.Hardware	HardwareConstants.IsTSRAIRSerialNumber()
DTS.Common.Events	ChartAxisChangedEvent, CursorsAlailableChangedEvent, GraphSelectedChannelsNotification, CursorShowMinMaxChangedEvent, ResetZoomChangedEvent, SaveToPDFRequestedEvent, ChartOptionsChangedEvent, CursorShowChangedEvent, CursorsClearChangedEvent
DTS.Common.Interface	IChartOptionsViewModel, IChartOptionsModel, IChartOptionsView, IBaseView, IViewerMainViewModel, IPSDReportMainViewModel, ITestChannel
DTS.Common.Interactivity	InteractionRequest<T>, Notification, Confirmation
Prism.Events	IEventAggregator
Prism.Regions	IRegionManager
Prism.Commands	DelegateCommand
Unity	IUnityContainer

Modules That Depend On This Module

Cannot be determined from source alone; would require analysis of consumers of IChartOptionsViewModel.

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5. Gotchas

1. Copy-Paste Error in XML Comment: The constructor's XML documentation states "Creates a new instance of the TestSummaryViewModel" — this is incorrect; the class is ChartOptionsViewModel.

2. Typo: ChartOptionsVisability: Property name should be ChartOptionsVisibility.

3. Typo: ShowCusor: Method name should be ShowCursor.

4. Typo: OnCursorsAlailableChanged: Event handler and event name CursorsAlailableChangedEvent should be CursorsAvailableChanged.

5. Hidden Base Members: Multiple properties (IsMenuIncluded, IsNavigationIncluded, IsBusy, IsDirty, ConfirmationRequest, Model, PropertyChanged, OnPropertyChanged) use the new keyword to hide base class members. This may cause unexpected behavior when casting to base types.

6. Unused IsDirty Property: The property has only a getter and is never assigned a value, making it perpetually false (default).

7. Commented-Out Constructor Code: Lines 55-57 are commented out, suggesting initialization logic was moved to Initialize(object parameter).

8. Hardcoded Magic Strings: Axis comparison uses literal strings "Y" and "X" in OnChartAxisChangedEvent; chartType comparison uses literal "Graph".

9. ADC/mV Support Detection: Both AllChannelsSupportADC and AllChannelsSupportmV use identical logic (checking for TSR AIR serial numbers). The comment indicates this is a temporary implementation that may need future refinement for calculated channels.