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vb.netitextpdf-generationitext7

iText Vertical Alignment in Text inside a Canvas isn't working

I'm trying to set my text which is inside a canvas to get vertically aligned with VerticalAlignment.BOTTOM property value, but whatever I put doesn't change the visual result.

retangulo = New iText.Kernel.Geom.Rectangle(122, AlturaPag - 208, 235, 27)
PdfCanvas = New iText.Kernel.Pdf.Canvas.PdfCanvas(page).SetLineWidth(1).Rectangle(retangulo).Stroke()
canvas = New iText.Layout.Canvas(PdfCanvas, retangulo)
texto = (New iText.Layout.Element.Text(Npagador).SetFontSize(11).SetBold)

' VerticalAlingment = BOTTOM \/     
paragrafo = (New iText.Layout.Element.Paragraph().Add(texto).SetTextAlignment(TextAlignment.LEFT).SetVerticalAlignment(VerticalAlignment.BOTTOM))
canvas.Add(paragrafo)

enter image description here

Solution

  • You are trying to align the contents of the paragraph to the bottom of the paragraph itself, and the paragraph when laying itself out simply uses the minimal necessary height, so whatever alignment (bottom or top) you set, the result it just the same simply because paragraph packs itself to the minimal height.

    To make sure setVerticalAlignment has an effect, you need to give the paragraph more vertical space by setting its height. Here is an example where I set paragraph height to match the height of the canvas you add it to, since it's the only element in the canvas. I also set the margins of the paragraph to zero so that you don't get additional spacing around the text.

    The code is in Java but you will be able to convert it back to VB.NET as easily as I converted your code to Java:

    Paragraph p = new Paragraph().add("Test").setTextAlignment(TextAlignment.LEFT)
        .setVerticalAlignment(VerticalAlignment.BOTTOM).setHeight(retangulo.getHeight());
p.setMargin(0);