org.apache.cocoon.forms.formmodel.algorithms
Class JavaScriptBuilder

java.lang.Object
  org.apache.cocoon.forms.formmodel.algorithms.JavaScriptBuilder

All Implemented Interfaces:

CalculatedFieldAlgorithmBuilder

public class JavaScriptBuilder
extends Object
implements CalculatedFieldAlgorithmBuilder

Javascript based calculated field algorithm builder.

With this algorithm the user can implement it's own algorithm directly in javascript and directly inside the form definition.

The syntax is as follows:

   <fd:value type="javascript" triggers="items,price,discount">
     var price = parent.lookupWidget('price').getValue();
     var items = parent.lookupWidget('items').getValue();
     var discount = parent.lookupWidget('discount').getValue();

     if (discount == 'completelyfree') return 0;
     var total = price * items;
     if (discount == 'halfprice') return total / 2;
       return total;
   </fd:value>
 

From inside the javascript function the following objects are accessible:

form

The form object.

parent

The parent widget. This is very useful in repeaters, since the parent is the repeater row.

cocoon and other FOM objects

This are accessible only when flowscript is in use (see bug COCOON-1804)

As you can see, the function must return the calculated value, and not set this directly in the widget. This way the value can be converted correctly if needed.

Version:

$Id: JavaScriptBuilder.html 1304258 2012-03-23 10:09:27Z ilgrosso $

Field Summary

Fields inherited from interface org.apache.cocoon.forms.formmodel.CalculatedFieldAlgorithmBuilder

ROLE

Constructor Summary

JavaScriptBuilder()

Method Summary

CalculatedFieldAlgorithm

build(Element algorithmElement)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

JavaScriptBuilder

public JavaScriptBuilder()

Method Detail

build

public CalculatedFieldAlgorithm build(Element algorithmElement)
                               throws Exception

Specified by:

build in interface CalculatedFieldAlgorithmBuilder

Throws:

Exception