DesktopDisplay.LastDisplayIndex
From Xojo Documentation
Read-Only Property (As Integer )
IntegerValue = aDesktopDisplay.LastDisplayIndex
New in 2021r3
Supported for all project types and targets.
New in 2021r3
Supported for all project types and targets.
The index of the last display connected to the user's computer. Display 0 is the main display. This can be useful when you need to loop through the user's displays.
Example
This example finds the maximum screen depth of all displays connected to the user's computer: