This is how you could return your processor with specific system settings.

gistfile1.php

<?php
class MyGetListProcessor extends modObjectGetProcessor {
    public $classKey = 'className';

    public function process() {
        $data = array();
        $settings = array(
            'emailsender' => $this->modx->getOption('emailsender')
        );
        $data['total'] = count($settings);
    	return $this->outputArray($settings, $data['total']);;
    }
}

return 'MyGetListProcessor';

Hi,

below is the working code (based on your sample)! The modObjectGetProcessor didn't work (at least I couldn't get it to work)

<?php
class GoodNewsGetSettingsProcessor extends modProcessor {

    public function process() {

        $settings = array(
            'resource_container'  => $this->modx->getOption('goodnews.resource_container'),
            'test_subject_prefix' => $this->modx->getOption('goodnews.test_subject_prefix'),
            // integer typecasting required to work with ExtJS.SliderField
            'mailing_bulk_size'   => (int)$this->modx->getOption('goodnews.mailing_bulk_size'),
            'admin_groups'        => $this->modx->getOption('goodnews.admin_groups'),
        );

        $response['success'] = true;
        $response['data'] = $settings;

        //$this->modx->log(modX::LOG_LEVEL_INFO, 'response: '.$this->modx->toJSON($response));

        return $this->modx->toJSON($response);
    }

}
return 'GoodNewsGetSettingsProcessor';

The class returns this Json string and all form field of the panel are filled with it's values:

{"success":true,"data":{"resource_container":"14","test_subject_prefix":"TEST - ","mailing_bulk_size":40,"admin_groups":"Administrator"}}

Thanks again for pushing me to the right direction!

Weird that modObjectGetProcessor didnt work since it extends modProcessor. Maybe it was missing a required variable. Good to see you got this working anyway and thanks for posting back your working example.