Excel VBA ComboBox1_DropButtonClick Event - vba

Question

I got macro below which fires twice (showing same MessageBox twice). First when ComboBox1 opens and second when ComboBox1 closes.
Private Sub ComboBox1_DropButtonClick()
If Me.ComboBox2.Text = "" Then
MsgBox "Fill text box"
Else
'Do stuff
End If
End Sub
Is there any way to make it show MessageBox once. I want user to select the value in ComboBox1 first before clicking on ComboBox2 DropButton.

Answer 1

Here is a very unelegant work-around using a "count" variable that prompts the MsgBox only the first and not the second time.
Dim count As Integer
Private Sub ComboBox1_DropButtonClick()
count = count + 1
If Me.ComboBox2.Text = "" Then
If count = 1 Then
MsgBox "Fill text box"
Else
count = 0
End If
Else
'Do stuff
End If
End Sub
However, I highly suggest to use the ComboBox1_Change() event if it's not necessary to use the drop button one.
P.S.: the declaration of the "count" variable needs to stay out of the method. This is due to the fact that:
if it stays inside, it's a local variable of the method and so loses its modifications every time the method is ended;
if it stays outside, it will keep the modifications even once the method has ended its run.

Answer 2

I would do it using the combobox_enter event, but this only checks when the focus is switched
Private Sub ComboBox1_Change()
If ComboBox1.Text = "" Then
ComboBox2.ShowDropButtonWhen = fmShowDropButtonWhenNever
Else
ComboBox2.ShowDropButtonWhen = fmShowDropButtonWhenAlways
End If
End Sub
Private Sub ComboBox2_Enter()
If ComboBox1.Text = "" Then
MsgBox "Must first set value to combobox1"
ComboBox1.SetFocus
End If
End Sub
Private Sub UserForm_Initialize()
ComboBox1.AddItem "None", 0
ComboBox1.AddItem "Select Me", 1
ComboBox2.AddItem "None", 0
ComboBox2.AddItem "Select Me", 1
ComboBox2.ShowDropButtonWhen = fmShowDropButtonWhenNever
End Sub
My code does some extra things that I just think look pretty, you really only need the _Enter function