Private Sub Workbook_SheetActivate(ByVal Sh As Object)
Dim ws As Worksheet
Dim x As Integer, wc As Integer
For Each ws In Worksheets
If ws.Visible = False Then wc = wc + 1
Next
For Each ws In Worksheets
If ws.Visible = False Then x = x + 1
If ws.Visible = True Then
ws.Range("A1").Value = "Feuille : " & ws.Index - x & " / " & Worksheets.Count - wc
End If
Next
End Sub