vba - VBA - CommandBars_OnUPdate - Which action /control has been triggered on the event?

Question

'Code in the Workbook class
Public WithEvents Bars As CommandBars

Public Sub Workbook_Open()
    Set Bars = Application.CommandBars
End Sub

Private Sub Bars_OnUpdate()
    'Try to determine which CommandBar Control has been triggered
    On Error Resume Next
    MsgBox Bars.ActionControl.TooltipText
    If Err.Number Then MsgBox Err.Number & " " & Err.Description
End Sub