ArcGIS Pro 2.7 API Reference Guide
PopupExtension Interface
Members 

ArcGIS.Desktop.Mapping Namespace : PopupExtension Interface
Allows popup creators to bind event handlers to popup window events.
Syntax
public interface PopupExtension 
Public Interface PopupExtension 
Requirements

Target Platforms: Windows 10, Windows 8.1

See Also

Reference

PopupExtension Members
ArcGIS.Desktop.Mapping Namespace