How to hide/unhide columns added at the borders of the range - vba

Question

I'm trying to create a macro which will hide/unhide a specified range of columns.
Adding a column within the named range isn't problematic, but when adding a column at the borders of this range - macro doesn't work. For example, AM:BF is the named range ("Furniture") in my sheet. I need to add a column BG which will also be hidden by the macro. Same story when adding a new column on the left border. Could you guide me how to improve the code so that the columns added at the borders of the range will also be hidden/unhidden?
With ThisWorkbook.Sheets("Sheet1").Range("Furniture").EntireColumn
.Hidden = Not .Hidden
End With

Answer 1

I've added a variable RangeName (of type String) that equals to the name of the Name Range = "Furniture".
Code
Option Explicit
Sub DynamicNamedRanges()
Dim WBName As Name
Dim RangeName As String
Dim FurnitureNameRange As Name
Dim Col As Object
Dim i As Long
RangeName = "Furniture" ' <-- a String representing the name of the "Named Range"
' loop through all Names in Workbook
For Each WBName In ThisWorkbook.Names
If WBName.Name Like RangeName Then '<-- search for name "Furniture"
Set FurnitureNameRange = WBName
Exit For
End If
Next WBName
' adding a column to the right of the named range (Column BG)
If Not FurnitureNameRange Is Nothing Then '<-- verify that the Name range "Furnitue" was found in workbook
FurnitureNameRange.RefersTo = FurnitureNameRange.RefersToRange.Resize(Range(RangeName).Rows.Count, Range(RangeName).Columns.Count + 1)
End If
' loop through all columns of Named Range and Hide/Unhide them
For i = 1 To FurnitureNameRange.RefersToRange.Columns.Count
With FurnitureNameRange.RefersToRange.Range(Cells(1, i), Cells(1, i)).EntireColumn
.Hidden = Not .Hidden
End With
Next i
End Sub

Answer 2

place the following in your worksheet code pane:
Option Explicit
Dim FurnitureNameRange As Name
Dim adjacentRng As Range
Dim colOffset As Long
Private Sub Worksheet_Change(ByVal Target As Range)
Dim newRng As Range
If colOffset = 1 Then Exit Sub
On Error GoTo ExitSub
Set adjacentRng = Range(adjacentRng.Address)
With ActiveSheet.Names
With .Item("Furniture")
Set newRng = .RefersToRange
.Delete
End With
.Add Name:="Furniture", RefersTo:="=" & ActiveSheet.Name & "!" & newRng.Offset(, colOffset).Resize(, newRng.Columns.Count + 1).Address
End With
ExitSub:
End Sub
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
On Error Resume Next
Set FurnitureNameRange = ActiveSheet.Names("Furniture") 'ThisWorkbook.Names("Furniture")
On Error GoTo 0
colOffset = 1
Set adjacentRng = Nothing
If FurnitureNameRange Is Nothing Then Exit Sub
Set adjacentRng = Target.EntireColumn
With FurnitureNameRange.RefersToRange
Select Case Target.EntireColumn.Column
Case .Columns(1).Column - 1
colOffset = -1
Case .Columns(.Columns.Count).Column + 1
colOffset = 0
End Select
End With
End Sub