Problems with PowerPoint Combobox to display items correctly

Question

I am creating PowerPoint in which I want users to be able to select an item from a list in a combo box. After that, nothing should happen, it is just to provide a recording on the screen of your choice.

My problem is that I seem to be able to populate the combo box and users can select the item, but the list grows as long as the combobox is clicked on it (is duplicated every time it clicks on the list). Or, alternatively, I can clear the combo box and then populate it, but in this case, the user selection also seems to be cleared.

Example VBA 1:

Private Sub ComboBox1_DropButtonClick()
With ComboBox1
.AddItem " ", 0
.AddItem "speed", 1
.AddItem "provisionality", 2
.AddItem "automation", 3
.AddItem "replication", 4
.AddItem "communicability", 5
.AddItem "multi-modality", 6
.AddItem "non-linearity", 7
.AddItem "capacity", 8
.AddItem "interactivity", 9
End With
End Sub

VBA Example 2:

Private Sub ComboBox1_DropButtonClick()
ComboBox1.Clear
With ComboBox1
.AddItem " ", 0
.AddItem "speed", 1
.AddItem "provisionality", 2
.AddItem "automation", 3
.AddItem "replication", 4
.AddItem "communicability", 5
.AddItem "multi-modality", 6
.AddItem "non-linearity", 7
.AddItem "capacity", 8
.AddItem "interactivity", 9
End With
End Sub

Can anyone help?

Answer 1

DropButtonClick, , , . , , :

Private Sub ComboBox1_DropButtonClick()

    If ComboBox1.ListCount = 0 Then
        With ComboBox1
            .AddItem " ", 0
            .AddItem "speed", 1
            .AddItem "provisionality", 2
            .AddItem "automation", 3
            .AddItem "replication", 4
            .AddItem "communicability", 5
            .AddItem "multi-modality", 6
            .AddItem "non-linearity", 7
            .AddItem "capacity", 8
            .AddItem "interactivity", 9
        End With
    End If

End Sub

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