In the book:
The examples in this free online tutorial will help you getting started
with iText. Note that most examples are two years old.
Some of the examples may be obsolete. Also the theory that
comes with the examples isn't always 100% accurate.
If you want more recent examples or if you want to know more
about the theoretical background of PDF and iText, please consult the book
"iText in Action".
Note that the first and the third chapter of the book
can be downloaded for free from http://manning.com/lowagie/
More specifically:
- Chapter 11: Adding color and text
PDF Syntax:
PDF Syntax to write text looks like this:
If you use any method mentioned below outside a beginText/endText block, your PDF reader will give you a 'damaged PDF file' warning or error.
Don't forget to use these methods!
Go to top of the pageBT /F13 12 Tf 288 720 Td (ABC) Tj ETThe example above write ABC (Tj) at a certain position (Tj) using a certain font (/F13) with a certain size (12). Text State is a subset of the graphics state and again iText offers lots of methods so that you don't have to write PDF syntax manually, but before looking at the lists of the text state, text positioning and text showing operators, you must know about the text object operators:
| BT | beginText() |
| ET | endText() |
Text State:
There are 9 graphics state parameters that only affect text (see table 5.1 in the PDF Reference Manual).
In the table below, I sum up the parameters (italic), the corresponding operators (bold, see table 5.2 in the Reference Manual)
and the corresponding iText method to change the text state.
Text also has it's own coordinate system: text space.
It is defined by the text matrix Tm and the text state parameters Tfs, Th and Trise,
which together form the transformation matrix text space to user space. This is the list of Text-positioning parameters
(see also Table 5.5 in the PDF Reference Manual):
Finally there are some text-showing operators (see Table 5.6 of the PDF Reference Manual).
iText also adds some extra methods that combine different methods that are summed up above:
showTextKerned(java.lang.String),
showTextAligned(int,%20java.lang.String,%20float,%20float,%20float) and
showTextAlignedKerned(int,%20java.lang.String,%20float,%20float,%20float).
This is a simple examples that writes some text at absolute positions:
Go to top of the page| Tc | Tc | setCharacterSpacing(float) |
| Tw | Tw | setWordSpacing(float) |
| Th | Th | setHorizontalScaling(float) |
| Tl | TL | setLeading(float) |
| Tf | Tf | setFontAndSize(com.lowagie.text.pdf.BaseFont, float) |
| Tfs | ||
| Tmode | Tr | setTextRenderingMode(int) The text rendering mode is one of the following values:
|
| Trise | Ts | setTextRise(float) |
| Tk | PdfGState.setTextKnockout(boolean) |
| Td | moveText(float, float) |
| Td | moveTextWithLeading(float, float) |
| Tm | setTextMatrix(float, float) setTextMatrix(float, float, float, float, float, float) |
| T* | newlineText() |
| Tj | showText(java.lang.String) |
| ' | newlineShowText(java.lang.String) |
| " | newlineShowText(float, float, java.lang.String) |
| TJ | showText(com.lowagie.text.pdf.PdfTextArray) |
This is a simple examples that writes some text at absolute positions:
Example: java
com.lowagie.examples.directcontent.text.Text
Adding text at absolute positions: see text.pdf
In this example, you see that graphics state methods also apply to text state:
text glyphs are shapes and if you want to change the color, you have to change the 'colorfill':
Adding text at absolute positions: see text.pdf
Fonts:
The first part of Chapter 5 of the PDF Reference Manual deals with
Text State;
the second part (starting with section 5.4) tells you all about fonts.
In this tutorial fonts are discussed in 3 chapters of a separate part:
Go to top of the pageIn this tutorial fonts are discussed in 3 chapters of a separate part:
