Private Sub SaveMultipleFixedContentDocumentsAsync(ByVal xpsdw As XpsDocumentWriter, ByVal fds As FixedDocumentSequence)
    _xpsdwActive = xpsdw

    AddHandler xpsdw.WritingCompleted, AddressOf AsyncSaveCompleted

    AddHandler xpsdw.WritingProgressChanged, AddressOf AsyncSavingProgress

    ' Write the FixedDocumentSequence as a
    ' collection of documents asynchronously.
    xpsdw.WriteAsync(fds)
End Sub


' Cancel an async operation
Public Sub CancelAsync()
    _xpsdwActive.CancelAsync()
End Sub
#End Region ' Asynchronous Save Methods


#Region "Async Event Handlers"
'
' Create an "async operation complete" event handler
' for saving a FixedDocumentSequence
'
Private Sub AsyncSaveCompleted(ByVal sender As Object, ByVal e As WritingCompletedEventArgs)
    Dim result As String
    If e.Cancelled Then
        result = "Canceled"
    ElseIf e.Error IsNot Nothing Then
        result = "Error"
    Else
        result = "Asynchronous operation Completed"
    End If

    ' Close the pakcage
    _xpsDocument.Close()

    If OnAsyncSaveChangeEvent IsNot Nothing Then
        Dim asyncInfo As New AsyncSaveEventArgs(result, True)
        RaiseEvent OnAsyncSaveChange(Me, asyncInfo)
    End If
End Sub

'
' Create an "async operation progress" event handler for
' monitoring the progress of saving a FixedDocumentSequence.
'
Private Sub AsyncSavingProgress(ByVal sender As Object, ByVal e As WritingProgressChangedEventArgs)
    _batchProgress += 1

    If OnAsyncSaveChangeEvent IsNot Nothing Then
        Dim progress As String = String.Format("{0} - {1}", e.WritingLevel.ToString(), e.Number.ToString())
        Dim asyncInfo As New AsyncSaveEventArgs(progress, False)
        RaiseEvent OnAsyncSaveChange(Me, asyncInfo)
    End If

    ' Call EndBatchWrite when serializing multiple visuals.
    If (_activeVtoXPSD IsNot Nothing) AndAlso (_batchProgress = 3) Then
        _activeVtoXPSD.EndBatchWrite()
    End If
End Sub