Multi Page PDF export of a Silverlight UI using SilverPDF - silverlight

Question

This is my first post and I'm really frustrated using Silverlight just because I'm a newbie in this.
I have three Silverlight UI (StackPanels basically) "stkMain1", "stkMain2" and "stkMain3".
I have to convert these three stack panels to PDF. I'm using silverPDF (I guess it further uses iTextSharp and PDFSharp.)
I've written the following code :
Private Sub cmdImage_Click(sender As Object, e As System.Windows.RoutedEventArgs) Handles cmdImage.Click
Dim d As New SaveFileDialog()
d.Filter = "PDF file format|*.pdf"
' Save the document...
If d.ShowDialog() = True Then
stkMain.Children.Clear()
stkMain.Children.Add(stkMain1)
Dim document As New PdfDocument()
Dim page As PdfPage = document.AddPage
Dim gfx As XGraphics = XGraphics.FromPdfPage(page)
Dim img As ImageTools.ExtendedImage = BillPage1.ToImage
Dim mstream As New MemoryStream()
Dim encoder As New JpegEncoder()
encoder.Encode(img, mstream)
mstream.Seek(0, SeekOrigin.Begin)
Dim pdfImg As XImage = XImage.FromStream(mstream)
gfx.DrawImage(pdfImg, 0, 0)
End If
End Sub
This does everything correct and gives one PDF file with one page.. Superb output and Thumbs up.
Now the real problem starts:
Private Sub cmdImage_Click(sender As Object, e As System.Windows.RoutedEventArgs) Handles cmdImage.Click
Dim d As New SaveFileDialog()
d.Filter = "PDF file format|*.pdf"
' Save the document...
If d.ShowDialog() = True Then
stkMain.Children.Clear()
stkMain.Children.Add(BillPage1)
Dim document As New PdfDocument()
Dim page As PdfPage = document.AddPage
Dim gfx As XGraphics = XGraphics.FromPdfPage(page)
Dim img As ImageTools.ExtendedImage = BillPage1.ToImage
Dim mstream As New MemoryStream()
Dim encoder As New JpegEncoder()
encoder.Encode(img, mstream)
mstream.Seek(0, SeekOrigin.Begin)
Dim pdfImg As XImage = XImage.FromStream(mstream)
gfx.DrawImage(pdfImg, 0, 0)
document.Pages.Add()
Dim page1 As PdfPage = document.AddPage
Dim gfx1 As XGraphics = XGraphics.FromPdfPage(page1)
Dim img1 As ImageTools.ExtendedImage = BillPage2.ToImage
Dim mstream1 As New MemoryStream()
Dim encoder1 As New JpegEncoder()
encoder1.Encode(img1, mstream1)
mstream1.Seek(0, SeekOrigin.Begin)
Dim pdfImg1 As XImage = XImage.FromStream(mstream1)
gfx1.DrawImage(pdfImg1, 0, 0)
document.Save(d.OpenFile())
End If
End Sub
Now this creates Two pages, and I get a scrambled output, contents of the stackpanels overlapping each other.
How to solve this?? I NEED HELP DESPERATELY. THE PROJECT IS DUE AND I HAVE TO SUBMIT IT BY 26th March 2011 (MONDAY).
Thanks in advance
Ravi

Answer 1

Try this:
If d.ShowDialog() = True Then
Dim document As New PdfDocument()
Dim page As PdfPage = document.AddPage
Dim pdfImg As XImage = DrawUI(stkMain1)
gfx.DrawImage(pdfImg, 20, 20)
page = document.AddPage()
gfx = XGraphics.FromPdfPage(page)
pdfImg = DrawUI(stkMain2)
page = document.AddPage()
gfx = XGraphics.FromPdfPage(page)
gfx.DrawImage(pdfImg, 20, 20)
pdfImg = DrawUI(stkMain3)
gfx.DrawImage(pdfImg, 20, 20)
document.Save(d.OpenFile())
End If
Private Function DrawUI(ByVal oControl As Object) As XImage
Dim img As ImageTools.ExtendedImage = ImageExtensions.ToImage(oControl)
Dim mstream As New MemoryStream()
Dim encoder As New JpegEncoder()
encoder.Encode(img, mstream)
mstream.Seek(0, SeekOrigin.Begin)
Dim pdfImg As XImage = XImage.FromStream(mstream)
Return pdfImg
End Function