SilverStripe 3.1.x add date range filters to modeladmin

SS-modelAdmin.php

<?php

class MyDataObjectAdmin extends ModelAdmin {

    private static $managed_models = array('MyDataObject'); // Can manage multiple models
    private static $url_segment = 'my-data-object'; // Linked as /admin/my-data-object/
    private static $menu_title = 'My DataObjects';


    public function getSearchContext() {
        $context = parent::getSearchContext();

        $dateField = new DateField("q[FromDate]", "From Date");

        // Get the DateField portion of the DatetimeField and
        // Explicitly set the desired date format and show a date picker
        $dateField->setConfig('dateformat', 'dd/MM/yyyy')->setConfig('showcalendar', true);
        $context->getFields()->push($dateField);


        $dateField = new DateField("q[ToDate]", "To Date");

        // Get the DateField portion of the DatetimeField and
        // Explicitly set the desired date format and show a date picker
        $dateField->setConfig('dateformat', 'dd/MM/yyyy')->setConfig('showcalendar', true);
        $context->getFields()->push($dateField);


        return $context;
    }



    public function getList() {
        $list = parent::getList();
        $params = $this->request->requestVar('q'); // use this to access search parameters
        if(isset($params['FromDate']) && $params['FromDate']) {
            $list = $list->exclude('Created:LessThan', $params['FromDate']);
        }

        if(isset($params['ToDate']) && $params['ToDate']) {

            //split UK date into day month year variables
            list($day,$month,$year) = sscanf($params['ToDate'], "%d/%d/%d");

            //date functions expect US date format, create new date object
            $date = new Datetime("$month/$day/$year");

            //create interval of Plus 1 Day (P1D)
            $interval = new DateInterval('P1D');

            //add interval to the date
            $date->add($interval);

            //use the new date value as the GreaterThan exclusion filter
            $list = $list->filter('Created:LessThan', date_format($date, 'd/m/Y'));
        }

        return $list;
    }

	    
}