ArcGIS Pro 3.0 API Reference Guide
ArcGIS.Desktop.Framework Namespace / Notification Class / ImageSource Property

ImageSource Property
Gets or sets the image to show. ImageUrl must be null for this property to work properly.
Syntax
public ImageSource ImageSource {get; set;}
Requirements

Target Platforms: Windows 11, Windows 10, Windows 8.1

ArcGIS Pro version: 2.8 or higher.
See Also