How would I remove focus from a listbox list item by clicking an empty area of the same listbox? Is this even possible?

What I know is possible: Remove focus by clicking on another control, or on the form, by setting the listindex to -1, and (overkill) make the form and controls have mousemove events to set the listindex to -1.

I know this is kind of trivial but I'm just curious as to whether it's possible or not.

I tried the below code with no result. I also tried using a -1 instead of the 0 with no result. If I use a 1 it takes away focus if the first item on the list is highlighted (leaving a dotted rectangle that can then be removed by setting focus to another control.)

Code:
Private Sub List1_Click()

    If (List1.ListIndex < 0) Then
        List1.ListIndex = -1
        RandomControl.SetFocus
    End If
    
End Sub