Adding Validation List with VBA is unstable - vba

Question

In SetWS sheet I have the following code in Worksheet_Deactivate:
Private Sub Worksheet_Deactivate()
Dim ActWS, SetWS As Worksheet
Set ActWS = ActiveWorkbook.Sheets("Activity_Plan")
Set SetWS = ActiveWorkbook.Sheets("Settings")
With ActWS.Range("J11:J20").Validation
.Delete
.Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, _
Operator:=xlBetween, Formula1:="=Settings!$AS$10:$AS$20" '
.IgnoreBlank = True
.InCellDropdown = True
End With '
End Sub
In RepWS sheet (where I only create a couple of graphs) I have the following code in Worksheet_Activate:
Private Sub Worksheet_Activate()
Application.EnableEvents = False
Application.ScreenUpdating = False
Application.Calculation = xlCalculationManual
Dim ScopeWS, RepWS, ActWS, SetWS As Worksheet
Set ScopeWS = ActiveWorkbook.Sheets("Scope")
Set RepWS = ActiveWorkbook.Sheets("Rep")
Set ActWS = ActiveWorkbook.Sheets("Activity_Plan")
Set SetWS = ActiveWorkbook.Sheets("Settings")
LRowScopeE = ScopeWS.Range("E" & Rows.Count).End(xlUp).Row
If SetWS.Range("W17") > SetWS.Range("W18") Then '
MsgBox ("bla bla")
Exit Sub
End If
RepWS.ChartObjects("Diagramm 3").Activate
ActiveChart.SeriesCollection(1).Name = "=Scope!$M$4"
ActiveChart.SeriesCollection(1).Values = "=Scope!$M$11:$M$" & LRowScopeE
ActiveChart.SeriesCollection(1).XValues = "=Scope!$E$11:$E$" & LRowScopeE
ActiveChart.SeriesCollection(2).Name = "=Scope!$P$4"
ActiveChart.SeriesCollection(2).Values = "=Scope!$P$11:$P$" & LRowScopeE
ActiveChart.SeriesCollection(3).Name = "=Scope!$U$4"
ActiveChart.SeriesCollection(3).Values = "=Scope!$T$11:$T$" & LRowScopeE
ActiveChart.Axes(xlValue).MaximumScaleIsAuto = True
ActiveChart.Axes(xlValue).TickLabels.NumberFormat = "#.##0 €"
ActiveChart.FullSeriesCollection(1).DataLabels.NumberFormat = "#.##0 €"
ActiveSheet.ChartObjects("Diagramm 14").Activate
ActiveChart.SeriesCollection(1).Name = "=Settings!$CJ$10"
ActiveChart.SeriesCollection(1).Values = "=Settings!$CJ$11:$CJ$" & SetWS.Range("CL8").Value
ActiveChart.SeriesCollection(1).XValues = "=Settings!$CI$11:$CI$" & SetWS.Range("CL8").Value
ActiveChart.SeriesCollection(2).Name = "=Settings!$CK$10"
ActiveChart.SeriesCollection(2).Values = "=Settings!$CK$11:$CK$" & SetWS.Range("CL8").Value
Application.EnableEvents = True
Application.Calculation = xlCalculationAutomatic
Application.ScreenUpdating = True
End Sub
When I switch from SetWS to RepWS, it throws an error
"Application defined or object defined error"
and highlights in SetWS the following:
.Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, _
Operator:=xlBetween, Formula1:="=Settings!$AS$10:$AS$20"
Switching between any other pair of sheets in this file does not cause this error (e.g. switching SetWS to any other sheet is OK).
UPDATE: I notice I more thing - As soon as I activate RepWS once, any further attempt to switch from SetWS to RepWS throws an error. Something is wrong with RepWS code...

Answer 1

Avoid the use of Active(Workbook/Sheet/Cell/Chart/...), the .Activate/.Select method and the .Selection property.
your worksheet_activate sub, might look something like this
Private Sub Worksheet_Activate()
Dim ScopeWS, RepWS, ActWS, SetWS As Worksheet
With Application
.EnableEvents = False
.ScreenUpdating = False
.Calculation = xlCalculationManual
End With
With ThisWorkbook
Set ScopeWS = .Sheets("Scope")
Set RepWS = .Sheets("Rep")
Set ActWS = .Sheets("Activity_Plan")
Set SetWS = .Sheets("Settings")
End With
LRowScopeE = ScopeWS.Range("E" & Rows.Count).End(xlUp).Row
If SetWS.Range("W17") > SetWS.Range("W18") Then '
MsgBox ("bla bla")
Else
With RepWS
'Diagram 3
With .ChartObjects("Diagram 3").Chart
'Series 1
With .SeriesCollection(1)
.Name = "=Scope!$M$4"
.Values = "=Scope!$M$11:$M$" & LRowSco
.XValues = "=Scope!$E$11:$E$" & LRowScopeE
End With
'Series 2
With .SeriesCollection(2)
.Name = "=Scope!$P$4"
.Values = "=Scope!$P$11:$P$" & LRowScopeE
End With
'Series 3
With .seriescolection(3)
.Name = "=Scope!$U$4"
.Values = "=Scope!$T$11:$T$" & LRowScopeE
End With
'Layout
With .Axes(xlValue)
.MaximumScaleIsAuto = True
.TickLabels.NumberFormat = "#.##0 €"
End With
.FullSeriesCollection(1).DataLabels.NumberFormat = "#.##0 €"
End With
'Diagram 14
With .ChartObjects("Diagram 14").Chart
'Series 1
With .SeriesCollection(1)
.Name = "=Settings!$CJ$10"
.Values = "=Settings!$CJ$11:$CJ$" & SetWS.Range("CL8").Value
.XValues = "=Settings!$CI$11:$CI$" & SetWS.Range("CL8").Value
End With
'Series 2
With .SeriesCollection(2)
.Name = "=Settings!$CK$10"
.Values = "=Settings!$CK$11:$CK$" & SetWS.Range("CL8").Value
End With
End With
End With
End If
With Application
.EnableEvents = True
.Calculation = xlCalculationAutomatic
.ScreenUpdating = True
End With
End Sub