Drop down list - auto fill capability?

'====================================
'Optional code to move to next cell if Tab or Enter are pressed
'from code by Ted Lanham
Private Sub TempCombo_KeyDown(ByVal _
        KeyCode As MSForms.ReturnInteger, _
        ByVal Shift As Integer)
    Select Case KeyCode
        Case 9 'Tab 
            ActiveCell.Offset(0, 1).Activate
        Case 13 'Enter 
            ActiveCell.Offset(1, 0).Activate
        Case Else
            'do nothing
    End Select
End Sub
'====================================

Option Explicit
' Developed by Contextures Inc.
' [URL="http://www.contextures.com"]www.contextures.com[/URL]
Private Sub DriversList_KeyDown(ByVal _
        KeyCode As MSForms.ReturnInteger, _
        ByVal Shift As Integer)
    'Hide combo box and move to next cell on Enter and Tab
    Select Case KeyCode
        Case 9
            ActiveCell.Offset(0, 1).Activate
        Case 13
            ActiveCell.Offset(1, 0).Activate
        Case Else
            'do nothing
    End Select
End Sub
Private Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel As Boolean)
Dim str As String
Dim cboTemp As OLEObject
Dim ws As Worksheet
Set ws = ActiveSheet
On Error GoTo errHandler
If Target.Validation.Type = 3 Then
Cancel = True
End If
Set cboTemp = ws.OLEObjects("DriversList")
  On Error Resume Next
  With cboTemp
    .ListFillRange = ""
    .LinkedCell = ""
    .Visible = False
  End With
On Error GoTo errHandler
  If Target.Validation.Type = 3 Then
    Application.EnableEvents = False
    str = Target.Validation.Formula1
    str = Right(str, Len(str) - 1)
    With cboTemp
      .Visible = True
      .Left = Target.Left
      .Top = Target.Top
      .Width = Target.Width + 15
      .Height = Target.Height + 5
      .ListFillRange = ws.Range(str).Address
      .LinkedCell = Target.Address
    End With
    cboTemp.Activate
  End If
  
errHandler:
  Application.EnableEvents = True
  Exit Sub
End Sub
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
Dim str As String
Dim cboTemp As OLEObject
Dim ws As Worksheet
Set ws = ActiveSheet
Set cboTemp = ws.OLEObjects("DriversList")
  On Error Resume Next
If cboTemp.Visible = True Then
  With cboTemp
    .Top = 10
    .Left = 10
    .ListFillRange = ""
    .LinkedCell = ""
    .Visible = False
    .Value = ""
  End With
End If
errHandler:
  Application.EnableEvents = True
  Exit Sub
End Sub