defined('_JEXEC') or die;
require_once dirname(__FILE__) . '/helper.php';
if(!defined('DS')) define('DS', DIRECTORY_SEPARATOR);
$filefinder = new FileFinder(JFactory::getApplication()->input->post->getString('path'));
require JModuleHelper::getLayoutPath('mod_filefinder');

class FileFinder
{
    public $currentdirectory = "";
    public $subdirectories = array();
    public $js = "";
    public $html = "";
    function __construct($path = null)
    {
        if (!$path) {
            chdir('../');
            $this->currentdirectory = basename(JPATH_BASE);
            $this->subdirectories = glob($this->currentdirectory.DS."*", GLOB_ONLYDIR);
            $this->html = "container";
            $this->js = "
                    jQuery(function($) {
                        $('#path').on('change', function() {
                        var path = $(this).val();
                        console.log({path: path});
                        $.ajax({
                            url: 'index.php?option=com_ajax&module=filefinder&method=FileFinder&format=raw',  // &ignoreMessages
                            type: 'POST',
                            async: true,
                            cache: false,
                            data: {path: path},
                            success: function(response){
                                console.log(response);
                            }
                        });
                    });
                    $('#path').trigger('change');
                });
             ";
        } else {
            $this->currentdirectory = $path;
            $this->subdirectories = glob($this->currentdirectory.DS."*", GLOB_ONLYDIR);
        }
    }

    public function FileFinderAjax() {
        ?><script>console.log('hello');</script><?php
        echo "hello";  // how do I get Ajax to get in here?!?
    }
}

defined('_JEXEC') or die;

if ($filefinder->html == "container") { // provide container with default contents
    echo "<div id="filefinder_container">";
        echo "<span>", JTEXT::_("Current Directory"), " ", $filefinder->currentdirectory, "</span>";
        echo "<select id="path"><option value="">Select a Subdirectory</option>";
        foreach ($filefinder->subdirectories as $subdirectory) {
            echo "<option>$subdirectory</option>";  //  value="$filefinder->currentdirectory".DS."$subdirectory"
        }
    echo "</select>";
    echo "</div>";
} else {  // return only the new contents to be inserted into old container
    echo "<span>", JTEXT::_("Current Directory"), " ", $filefinder->currentdirectory, "</span>";
    echo "<select id="path"><option value="">Select a Subdirectory</option>";
    foreach ($filefinder->subdirectories as $subdirectory) {
        echo "<option>$subdirectory</option>";  //  value="$filefinder->currentdirectory".DS."$subdirectory"
    }
    echo "</select>";
}
if ($filefinder->js) {
    JHtml::_('jquery.framework');
    $document = JFactory::getDocument();
    $document->addScriptDeclaration($filefinder->js);
}

{path: "administratorcache"}
POST http://localhost/jdem01/administrator/index.php?option=com_ajax&module=filefinder&method=FileFinder&format=raw 404 (Not Found)