DesktopListBox.LastRowIndex

From Xojo Documentation

Read-Only Property (As Integer )
IntegerValue = aDesktopListBox.LastRowIndex

New in 2021r3

Supported for all project types and targets.

The number of the last row of the DesktopListBox. Like nearly all of Xojo, the DesktopListBox is zero-based which means this value will be 1 less than the DesktopListBox.RowCount.