DP44/docs/ai/Common/DTS.CommonCore/Events/RegionOfInterest.md

source_files, generated_at, model, schema_version, sha256

source_files	generated_at	model	schema_version	sha256
Common/DTS.CommonCore/Events/RegionOfInterest/RegionOfInterestChangedEvent.cs	2026-04-17T16:39:19.158808+00:00	zai-org/GLM-5-FP8	1	e442143e0642d03f

Documentation: RegionOfInterestChangedEvent

1. Purpose

This module defines RegionOfInterestChangedEvent, a typed event class for use with the Prism Event Aggregator pattern. It enables loosely-coupled publication and subscription of region-of-interest change notifications across the application. The event carries an IRegionOfInterest payload, allowing subscribers to react to changes in the active or selected region without direct coupling to the publisher.

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2. Public Interface

RegionOfInterestChangedEvent

Signature:

public class RegionOfInterestChangedEvent : CompositePresentationEvent<IRegionOfInterest> { }

Description:
An empty class that inherits from CompositePresentationEvent<IRegionOfInterest>. It serves as a type identifier for the Prism Event Aggregator, defining an event that publishes/subscribes to IRegionOfInterest instances. No additional members are defined; all functionality is inherited from the base class.

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3. Invariants

• The event payload type is fixed to IRegionOfInterest; subscribers will receive objects implementing this interface.
• The class must remain instantiable (it is not static or abstract), allowing the Event Aggregator to create instances as needed.
• Inheritance from CompositePresentationEvent<T> is required for integration with Prism's IEventAggregator.

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4. Dependencies

This module depends on:

• DTS.Common.Interface.RegionOfInterest.IRegionOfInterest — the interface defining the event payload contract.
• Microsoft.Practices.Prism.Events.CompositePresentationEvent<T> — the Prism base class for typed events.

What depends on this module:

• Unknown from source alone. Consumers would typically be modules that publish or subscribe to region-of-interest changes via the Event Aggregator.

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5. Gotchas

• Older Prism namespace: The import Microsoft.Practices.Prism.Events indicates use of an older version of Prism (pre-.NET Core/NET5+). Modern Prism uses Prism.Events. This may affect migration or cross-version compatibility.
• Empty class by design: The class body is intentionally empty. It relies entirely on the base class for functionality. Do not add instance members; thread-safe subscription options are provided by the base CompositePresentationEvent<T>.