Crie um formulário com os controles ComboBox1 e CommandButton1 e insira o código abaixo:
Option Explicit
Private Sub CommandButton1_Click()
With Me.ComboBox1
If .ListIndex = .ListCount - 1 Then
.ListIndex = 0
Else
.ListIndex = .ListIndex + 1
End If
End With
End Sub
Private Sub UserForm_Initialize()
With Me.ComboBox1
.AddItem ""
.AddItem "Sala"
.AddItem "Quarto"
.AddItem "Banheiro"
.ListIndex = 0
End With
End Sub
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