<?php

// highlight file option..
if( !empty($_GET['source']) ) {
    echo 
    "<a href='linkselectfields2.php'>Back</a>\n".
    "<br />\n".
    "<hr size='1' />\n";
    highlight_file( __FILE__ );
    exit;
} 

// include formhandler
include('../includes/FH3/class.FormHandler.php');

$filter = $_POST['filter'];

// switch which field is changed
switch( $_POST['field'] ) {
    
    // select the right town
    case 'town':
          // is a country selected?
          if( $filter != 0 ) {
              // here you can select the items which
              // should be loaded in the "town" field
              // You can use $filter to select
              // the town's which are linked tho that specific country         
              
              // After selecting the town's, put them into an array and
              // pass them to the setDynamicOptions method like below
              
              if( $filter == 1 ) {
                  $towns = array(
                    0 => '-- Select --',
                    1 => 'Town 1a',
                    2 => 'Town 1b'
                  );
              } else {
                  $towns = array(
                    0 => '-- Select --',
                    3 => 'Town 2a',
                    4 => 'Town 2b'
                  );  
              }
              
              FormHandler::setDynamicOptions( $towns );
          }
          break;
      
    case 'street':
        switch( $filter ) { 
            // town 1a is selected
            case 1: 
              $streets = array(
                'street 1a I'=>'street 1a I',
                'street 1a II'=>'street 1a II'
              );
              break;
            // town 1b is selected
            case 2: 
              $streets = array( 
                'street 1b I'=>'street 1b I',
                'street 1b II'=>'street 1b II'
              );
              break;
            // town 2a is selected  
            case 3:
              $streets = array( 
                'street 2a I'=>'street 2a I',
                'street 2b II'=>'street 2b II'
              );
              break;         
            // town 2b is selected  
            case 4:
              $streets = array( 
                'street 2b I'=>'street 2b I',
                'street 2b II'=>'street 2b II'
              );
              break;
            // when no town is selected...  
            default:  
              $streets = array();
              break;
        }
        
        FormHandler::setDynamicOptions( $streets );
          break;      
    
    default:
      FormHandler::setDynamicOptions(
        array(
          'Given filter: '.$filter,
          'Load options of field: '.$_POST['field']
          )
      );
      break;          
} 

?>