Hide Rows / Autofilter Listener - OpenOffice Basic - listener

Question

I need to dev Listener to detect changes of isVisible setting for a rows in calc.
Even better it would be for me to have autofilter changes listener - this is also beyond my skills. I would be appreciative for any or both solutions help.
XEventListener nor XModifyListener dont detects this changes.
Maybe try to use XChangesListener XChangesNotifier? <- anyway, i had problem to implement it for tests too
Sub add_eventsListener
Dim ePrefix As String, eService As String
ePrefix = "event_"
eService = "com.sun.star.document.XEventListener"
If IsNull(mEventHandler) Then
mEventHandler = CreateUnoListener(ePrefix, eService)
ThisComponent.addEventListener(mEventHandler)
EndIf
End Sub
Sub event_notifyEvent(oEvent)
msgbox "event: " & oEvent.EventName
End Sub
Sub add_modifyListener(ByRef Sheet)
Dim ePrefix As String : Dim eService As String
Dim cell as Object
ePrefix = "event_"
eService = "com.sun.star.util.XModifyListener"
cell = Sheet.getCellrangeByName("A2:A9")
If IsNull(mModifyHandler) Then
mModifyHandler = CreateUnoListener(ePrefix, eService)
cell.AddModifyListener(mModifyHandler)
EndIf
End Sub
Sub event_modified(oEvent)
'If oEvent.Source.CellAddress.Column <> 0 Then Exit Sub
Msgbox "changes made"
End Sub
where mEventHandler and mModifyHandler are global
Sub add_autofilter(ByRef Sheet)
On Error GoTo Err
Dim Range As New com.sun.star.table.CellRangeAddress
Dim FilterOn As Boolean, dRange As Object, cell As Object, row%
FilterOn = False
cell = Sheet.getCellRangeByName("A1")
row = getLastRow(Sheet)
On Error Resume Next
dRange = ThisComponent.DatabaseRanges.getByName("Symbols")
FilterOn = dRange.AutoFilter
On Error GoTo 0 : On Error GoTo Err
If FilterOn Then Exit Sub
With Range
.Sheet = 0
.StartColumn = 0
.StartRow = 0
.EndColumn = 0
.EndRow = row
End With
'Range = Sheet.getCellRangeByPosition(0, 0, 0, row)
ThisComponent.DatabaseRanges.addNewByName("Symbols", Range)
ThisComponent.DatabaseRanges.getByName("Symbols").AutoFilter = True
Exit Sub
Err:
End Sub
Function getLastRow(ByRef Sheet) As Integer
Dim cursor
cursor = Sheet.createCursor()
cursor.gotoEndOfUsedArea(false)
getLastRow = cursor.getRangeAddress().EndRow
End Function

Answer 1

While I am waiting for rational solution, I found a workaround - If no autofilter listener will be possible, Ill have to stay with that:
add formula in some cell: (old solution, check EDIT below)
"=IF(NOW()>0;ROWS_FILTERED();0)"
Function ROWS_FILTERED() As Integer
If Freezed Then Exit Function
Dim i%, rows%, Sheet As Object : Sheet = ThisComponent.Sheets(0)
rows = getLastRow(Sheet)
For i = 1 to getLastRow(Sheet) 'row 0 is for labels
If Sheet.Rows(i).IsVisible = True Then
rows = rows - 1
End If
Next i
ROWS_FILTERED = rows
End Function
And if you make changes where computations are not expected, just assign True to Global Freezed for that time
EDIT:
eureka! I have found this shiny formula that works and updating without workaround:
Eureka! Mimo że nie osiągnąłem rezultatu z czystego BASIC'a, znalazłem genialną formułę, która się odnosi bezpośrednio do autofiltra!! i updateuje bez obejścia:
"=SUBTOTAL(3;A2:A" & getLastRow(Sheet) + 1 & ")"
dont forget to include getLastRow(ByRef Sheet) function to your code