Creating a New Form Field

From IHRIS Wiki

This tutorial applies to version 4.0 of the iHRIS Suite.

In this tutorial, we will create new form field data type. This form field will be a one line string which is capitalized. The capitalization will be enforced on the server-side as well as the client-side via java-script. We will wrap all of this into a module, CapField so that it can be shared easily.

Creating the Module

In one of your module directories (e.g. your site's modules directory) do the following:

mkdir CapField
gedit CapField/CapField.xml

and add in the following lines: <source lang='xml'>

<?xml version="1.0"?>       

<!DOCTYPE I2CEConfiguration SYSTEM "I2CE_Configuration.dtd"> <I2CEConfiguration name='CapField'>

   <displayName>Capitalized Field</displayName>   
   <category>System Component</category>
   <description>Provides an always capitalized field</description>
   <creator>Intrahealth Informatics</creator>
   <requirement name='i2ce'>
     <atleast version='4.0'/>
     <lessThan version='4.1'/>
   <path name='classes'>
 <configurationGroup name='CapField' path='/'>
   <configuration name='STRING_CAP' path='/modules/forms/FORMFIELD/STRING_CAP'>

<I2CEConfiguration> </source>


We need to create a PHP class to handle the client-side validation of our capitalized field. The field we want has input which is a one line string, so we will subclass the existing one. We do this as follows:

mkdir CapField/lib
gedit CapField/lib/I2CE_FormField_STRING_CAP.php

and add in the following: <source lang='php'>

class I2CE_FormField_STRING_CAP extends I2CE_FormField_STRING_LINE  {
    * Checks to see if the current value for this is set and valid.
    * This function is used to validate the input on the server-side. 
    * We first check to see if it is valid using the parent class' validation method.  
    * If this passes, we then check the the capitalized version of the value we have is the same
    * as the value we have (if so it is already capitalized and is thus valid)
    * @return boolean
   public function isValid() {
       if (!parent::isValid()) {
          return false;
       $value = $this->getValue();
       return ($value === ucwords($value));

    *This is the method to create the input element for the capitalized input string
    * @param DOMNode $node  The node that we wish to add out input element to
    * @param I2CE_Tempalte $template.  The page template object that we are working in
    * @parma DOMNode $form_node  The node from the html template file that requested this form field be displayed
   public function processDOMEditable($node,$template,$form_node) {
       $ele_name = $this->getHTMLName();  //this gets the name of the input element which is used for the GET and POST variables
       $template->addHeaderLink('mootools.js'); //makes sure that the mootools javascript library is avaiable to us
       $element = $template->createElement(  //creates the input element that we will add 
                   "name" => $ele_name, 
                   "id" => $ele_name, 
                   "type" => "text", 
                   "onblur"=> "this.setValue(this.getValue().capitalize());"
                   "value" => $this->getDBValue() 
                   ) );
       $this->setElement($element);  //registers the input element that we created
       $node->appendChild( $element);  //add the input element node we just created to the node it needs to be under

} </source>


In the processDOMEditable() function we added some javascript for the onblur check. iHRIS uses version 1.2 of the mootools javascript library. Mootools has a handy capitalization function that we incorporated into our form field so that on a "blur" event the input element will capitalize.

Finishing Up

You are done, you just need to require the module you created where appropriate. You can now add a field to a form with type STRING_CAP.