I would like to find out information about the layout of text in a
PdfPCell. I'm aware of
BaseFont.getWidthPointKerned(), but I'm looking for more detailed information like:
- How many lines would a string need if rendered in a cell of a given width (say, 30pt)? What would the height in points of the
- Give me the prefix or suffix of a string that fits in a cell of a given width and height. That is, if I have to render the text "Today is a good day to die" in a specific font in a
PdfPCellof width 12pt and height 20pt, what portion of the string would fit in the available space?
- Where does iText break a given string when asked to render it in a cell of a given width?
iText uses the
ColumnText class to render content to a cell.
ColumnText measures the width of the characters and tests if they fit the available width. If not, the text is split. You can change the split behavior in different ways: by introducing hyphenation or by defining a custom split character.
I've written a small proof of concept to show how you could implement custom "truncation" behavior. See the TruncateTextInCell example.
Instead of adding the content to the cell, I have an empty cell for which I define a cell event. I pass the long text
"D2 is a cell with more content than we can fit into the cell." to this event.
In the event, I use a fancy algorithm: I want the text to be truncated in the middle and insert "..." at the place where I truncated the text.
BaseFont bf = BaseFont.createFont(); Font font = new Font(bf, 12); float availableWidth = position.getWidth(); int contentLength = content.length(); int leftChar = 0; int rightChar = contentLength - 1; availableWidth -= bf.getWidthPoint("...", 12); while (leftChar 0) leftChar++; else break; availableWidth -= bf.getWidthPoint(content.charAt(rightChar), 12); if (availableWidth > 0) rightChar--; else break; } String newContent = content.substring(0, leftChar) + "..." + content.substring(rightChar); PdfContentByte canvas = canvases[PdfPTable.TEXTCANVAS]; ColumnText ct = new ColumnText(canvas); ct.setSimpleColumn(position); ct.addElement(new Paragraph(newContent, font)); ct.go();
As you can see, we get the available width from the
position parameter and we check how many characters match, alternating between a character at the start and a character at the end of the content.
The result is shown in the resulting PDF: the content is truncated like this:
"D2 is a c... the cell."
Your question about "how many lines" can be solved in a similar way. The
ColumnText class has a
getLinesWritten() method that gives you that information. You can find more info about positioning a
ColumnText object in my answer to your other question: How to tell iText how to clip text to fit in a cell?"