Loop through form header for controls null values

Hello, I have a form with just combo boxes and text boxes and I need to loop through all the controls in just the forms header in order to show a few hidden buttons if everything has a value and if not show message and dont show buttons

I don't usually do Access, but something like this

Code:

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Dim Ctrl As Object
Dim MissingValues as boolean

For Each Ctrl in Me.Controls
  If Ctrl.ControlType = acTextBox then
    If Ctrl.Value = "" Then
        MissingValues = True
        Exit For
    End IF
  ElseIf Ctrl.ControlType = acListtBox then
    If Ctrl.Value = "" Then
        MissingValues = True
        Exit For
    End IF
  End if
Next

If MissingValues Then
  Show message
Else
  Show buttons

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