ArcGIS Pro 3.4 API Reference Guide
ArcGIS.Desktop.Framework.Contracts Namespace / CustomControl Class / OnDropDownOpened Method
Version

OnDropDownOpened Method (CustomControl)
If the CustomControl specifies the DAML attribute 'isDrop=true', this function is called whenever its drop-down is opened.
Syntax
protected internal virtual void OnDropDownOpened()
Requirements

Target Platforms: Windows 11, Windows 10

ArcGIS Pro version: 3 or higher.
See Also