Hide rows section of code not working with other macro code - excel

Question

I have been trying to have two independent codes change my worksheet based on either a cell value or a data validation selection. To try to highlight what my intent is I have a database of Steel Structural members I am trying to create a worksheet that the end user will select if they want US or Metric Units. Based on that selection I need either row 11 or 12 to be hidden. I already have a macro attached to the worksheet that will enter the user's selection from a data validation list into subsequent columns. To further explain my end goal: Row 11 is the Members in US units and 12 is the Metric Units. If the end user selects US they will not see the Metric Row, and vise versa.
Option Explicit
Private Sub Worksheet_Change(ByVal Target As Range)
On Error GoTo exitHandler
Dim rngDV As Range
Dim iCol As Integer
If Target.Count > 1 Then GoTo exitHandler
On Error Resume Next
Set rngDV = Cells.SpecialCells(xlCellTypeAllValidation)
On Error GoTo exitHandler
If rngDV Is Nothing Then GoTo exitHandler
If Intersect(Target, rngDV) Is Nothing Then
'do nothing
Else
Application.EnableEvents = False
If Target.Column = 3 Then
If Target.Value = "" Then GoTo exitHandler
If Target.Validation.Value = True Then
iCol = Cells(Target.Row, Columns.Count).End(xlToLeft).Column + 2
Cells(Target.Row, iCol).Value = Target.Value
Else
MsgBox "Invalid entry"
Target.Activate
End If
End If
End If
exitHandler:
Application.EnableEvents = True
If Target.Address = "$AS$7" Then
Rows("11").Hidden = (Target.Value = "Metric")
Rows("12").Hidden = (Target.Value = "US Standard")
End If
End Sub
I had them as two Worksheet_Change events and had a compiler error, and I have tried to break the two programs into individual sub routines ie:
Private Sub Worksheet_Change(ByVal Target As Range)
SelectStructural Target
HideRow Target
End Sub
Sub SelectStructural (ByVal Target As Range)
...
End Sub
Sub HideRow (ByVal Target As Range)
...
End Sub
Where ... is representative of the previouly mentioned code. And in that case as with above the macro which inputs the member into subsequent columns works but not the row hide routine.
Many thanks in advance.

Answer 1

Here is what I would do to fix your problem. I wouldn't have a worksheet_change event for this at all, because every time anyone types a thing, this code will have to run. Have some other place where the user selects US or Metric and when THAT changes, you can have the event go off.
Determine the point where the user enters US or Metric.
Sub MetricCheck_Change(ByVal Target As Range)
Dim userChoice as String
userChoice = LCase(Sheets("Sheet1").Range("A1")) 'Convert a user input to lowercase
If userChoice = "us" Then
Call UsSub
ElseIf userChoice = "metric" Then
Call MetricSub
Else
MsgBox("Neither US or Metric has been selected. Please select to continue.")
End If
End Sub
Have a sub that Shows the US row, and hides the Metric. Just record a macro that does just that, and put it here.
Sub UsSub()
'Show the US Row
'Hide the Metric Row
End Sub
Do the opposite for the Metric Sub
Sub MetricSub
'Hide the US Row
'Show the Metric Row
End Sub