ubxml2pdf: Using xml to create a pdf form

ubxml2pdf – Using xml to make a pdf form

ubxml2pdf uses an xml structure to produce forms. From simple to complex, ubxml2pdf can make your form.

The basic principle is to create a background form and then add lines to it. When the current page is full a new page with the background form is started.

Hello World!

Every language has a simple “Hello World!” program.

Here is the simple ubxml2pdf program.

<?xml version="1.0"?>
 <document>
 <form>
 <head>
 <box llx="0" lly="0" urx="8.5" ury="11.5" />
 </head>
 <body><line><text>Hello World!</text></line></body>
 <foot />
 </form>
 </document>

This shows the basic components of a document.

You can test this by editing a file to contain the above text and then using curl to send it to our pdf server:

cat test.xml | curl -s --form USER=rjm@hypedc:L1e9V7y2 --form PROCESS=ubxml2pdf --form FILENAME=@- http://uniquote.zenucom.com/cgi-bin/service

Some explanation:

<?xml version=”1.0″?>

standard xml processing command

<document> The root document. IT has options that apply to the whole document, but can be called by itself.

<form> A ubxml2pdf form consists of multiple forms, each with it’s own characteristics. Forms always start on a new page. eg You could have a form that is an invoice followed by a standard form that is terms and conditions of sale.

<head>, <body>, <foot>. Like an html table, a form is divided into a heading, body, section, and footer. Unlike an html table they are specified in the order you expect to see them.

Elements in the <head> section are put on every page. The background form if you like.

<body> has a restricted set of elements that are the lines on the form.

<tail> is cleanup at the end of the form such as a total.

<head> and <foot> sections are composed of boxes that are positioned absolutely on the page. The last box of the <head> section is the <box> used for the <body>.

Within a <box> you can have <bar> to put vertical bars in a box.

You can also have <line>, <imagetab>, <newpage>, <rule>, <barcode> (explained later).

The <box> element that defines the <body> can also have a special <heading> element. More on that later.

The simplest element is a <line> that has <text> and <image>.

Background and foreground colours and shades

Before we build a form, just a note on using gray scale (shades) and colours. These can be either background or foreground.

Colours and shades are specified as attributes of many elements: form, head, body, tail, box, line, text.

Gray scale is specified as a factor of black to white. 0 = black. 1 = white. A decimal (eg 0.5) represents the amount of white.

Colours work the same, except you specify the amount of red, green, and blue. Again as a decimal. Specifying some of each colour will give more complex colours. Much the same as you would with html (0..255 instead of 0..1).

Either shade or a factor of read, green, and blue can be given. But not both.

e.g.

<box background-shade="0.5" red="0.5" blue="0.5">
<line><text>Hello World!</text></line>
</box>

This produces magento text on a gray background.

It is important to recognise at this point that these characteristics are inherited from one level to the next.

<box background-shade="0.5" red="0.5" blue="0.5">
<line><text>Hello </text><text red="1" green="1">World!</text></line>
</box>

Building your form

The first thing to do is build the background for your form.

This consists of lots of boxes absolutely position on the page.

A box has a position, background, borders, and then contains lines.