Private Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel As Boolean)
Dim Valeur As String
Dim Couleur As Long
Select Case Target.Value
Case "": Valeur = 8: Couleur = 1
Case 8: Valeur = 4: Couleur = 2
Case 4: Valeur = "": Couleur = 3
End Select
Target.Interior.color = Choose(Couleur, RGB(255, 0, 0), RGB(0, 0, 255), RGB(255, 255, 255))
Target = Valeur
Cancel = True
End Sub