Problem to show graph in preview mode on in report - ms-access

Question

I have a form with a graphic and after modifying a certain field in the form, I change the number of graphic's records in this way:
Private Sub text_Cantidad_BeforeUpdate(Cancel As Integer)
Dim strsql As String
sql = "SELECT TOP " & CStr(text_Cantidad) & "Format([hora1],""hh:nn:ss"") AS Hora, TEMP_SET_POINT, TEMP_PAST_2 " & _
" , TEMP_PASTEURIZAD " & _
" FROM Qry_Registro WHERE Carpeta = '" & onodo.Parent.Text & "' AND Archivo = '" & Trim(onodo.Text) & _
"' ORDER BY Format([hora1],""hh:nn:ss""), Right(Format([hora1],""hh:nn:ss""),2);"
With Me.Gráfico1
.RowSourceType = "Table/Query"
.RowSource = sql
.Visible = True
.Object.Application.PlotBy = 2
End With
End Sub
Then with a button I want to print a report that has the same graph with the same properties and the same records. If I open the report in "report mode" everything is fine, but if I do it in "preview mode" I cannot change the recordsource property in any of the report or section's events.
The code I have for the button so far is:
Private Sub btn_Print_Click()
Dim strsql As String
TempVars.Add "SqlReport", ""
TempVars!SqlInformed = Me.Gráfico1.RowSource
'Error
DoCmd.OpenReport "Report", acViewPreview
'Ok
DoCmd.OpenReport "Informe1",acViewNormal
End Sub

Answer 1

The recordsource of a report can't be changed after the report is opened.
You shouldn't use dynamic sql to change the query of a form or report. If possible, use a WhereCondition parameter in the DoCmd.OpenForm or DoCmd.OpenReport statement. If your query Qry_Registro contains something like a unique ID, you can remove the dynamic "TOP" part from the report's query and replace it by a criterion for a WHERE clause using a subquery:
... WHERE ID IN (SELECT TOP x ID FROM ...
Placing all criteria in a variable, you can use that in the DoCmd.OpenReport statement.
strWhereClause = "ID IN (SELECT TOP " & CStr(text_Cantidad) & " ID FROM Qry_Registro " & _
"WHERE Carpeta = '" & onodo.Parent.Text & "' AND Archivo = '" & Trim(onodo.Text) & "' " & _
" ORDER BY Format([hora1], ""Long Time""))"
DoCmd.OpenReport ReportName:="MyReport", View:=acViewPreview, WhereCondition:=strWhereClause

Answer 2

Thanks a lot Wolfgang, but the issue is change the recordsource of chart in report. I solved placing in the properties of chart a query, then before open de report changed the propertie sql of querydef with the same sql that chart in form. Something like this
set querydef = currentdb.Querydefs("query_report_chart")
querydef.sql = "SELECT TOP " & CStr(text_Cantidad) & ....
DoCmd.OpenReport
Regards