Collect only one of the values in a combobox

Hi All,

I have the following code to collect only one of the values in row C into a ComboBox1.

Now I want to change the code so that it still does the same, but than collect only the values from the visible cells.

Dim myCollection As New Collection
Dim oneCell As Range
Dim oneString As Variant

For Each oneCell In Range(Range("C2"), Range("C65536").End(xlUp))
   On Error Resume Next
   For Each oneString In Split(CStr(oneCell.Value), ",")
       myCollection.Add Item:=oneString, Key:=oneString
   Next oneString
   On Error GoTo 0
Next oneCell

With UserForm1.ComboBox1
   For Each oneString In myCollection
        .AddItem oneString
   Next oneString
End With