Excel VBA adding data to a chart - vba

Question

Hello I have a little question for adding data to an existing chart.
Now I have a worksheet containing a data series with months for the years in the 2nd row of the sheet. So the months are for example B2 1.2017, C2 2.2017, and in the rows 3,4,5,6,7 and 8 there is always data for that month.
Now I just want my macro to add the new Month plus the data of the rows below to my existing chart.
the code I have so far is this:
Worksheets("Summary").ChartObjects("Chart").Activate
ActiveChart.SeriesCollection.Add _
Source:=Worksheets("Summary").Range("B2:B8")
now this does just create new data series but there is actually no new data added to the chart.

Answer 1

The code below might seem a little long, but it's the safest way to add a new Series with Data to an existing Chart.
I'm setting all the necessary Objects so the code will be as "safe-proof" as can be.
Code
Option Explicit
Sub AddSeriestoChart()
Dim ws As Worksheet
Dim ChtRng As Range
Dim ChtObj As ChartObject
Dim Ser As Series
' set the Worksheet object
Set ws = ThisWorkbook.Worksheets("Summary")
' Set the Chart Object
Set ChtObj = ws.ChartObjects("Chart")
' Set the Range of the Chart's source data
Set ChtRng = ws.Range("B2:B8")
With ChtObj
' add a new series to chart
Set Ser = .Chart.SeriesCollection.NewSeries
' set the source data of the new series
Ser.Values = "=" & ChtRng.Address(False, False, xlA1, xlExternal)
End With
End Sub
Edit 1: to modify existing Series data, use something like the code below :
With ChtObj
For i = 1 To .Chart.SeriesCollection.Count
Set Ser = .Chart.SeriesCollection(i)
' set the source data of the new series
Set ChtRng = ws.Range("B" & i + 2)
Ser.Values = "=" & ChtRng.Address(False, False, xlA1, xlExternal)
Set ChtRng = Nothing
Next i
End With

Answer 2

This is what I would use
wsMetric.ChartObjects("Chart").Chart
'This one will link data from another workbook
.SeriesCollection(1).Values = "='[" & wb.Name & "]" & ws.Name & "'!$" & sCol & "$" & lRow & ":$" & sCol2 & "$" & lRow2
'Debug.Print "='[" & wb.Name & "]" & ws.Name & "'!$" & sCol & "$" & lRow & ":$" & sCol2 & "$" & lRow2 'Returns ='[Book1.xlsm]Sheet1'!$A$1:$A$11
'This one will link data from the same workbook, same or different sheet
.SeriesCollection(1).Values = "=" & ws.Name & "!$" & sCol & "$" & lRow & ":$" & sCol2 & "$" & lRow 2
'Debug.print "=" & ActiveSheet.Name & "!$" & scol & "$" & lrow & ":$" & scol2 & "$" & lrow2 'Returns =Sheet1!$A$1:$A$11
End With
This doesn't use .Activate and directly accesses the chart