protected function _getElementHtml($element)
 {
     $element->setData('onchange', "apiValidation(this.form, this);");
     $url = $this->getUrl('*/connector/ajaxvalidation');
     $element->setData('after_element_html', "\n            <script>\n                document.observe('dom:loaded', function(){\n                    apiValidation();\n\n                 });\n                function apiValidation(form, element) {\n                    var api_user       = \$('connector_transactional_emails_credentials_api_username');\n                    var api_password   = \$('connector_transactional_emails_credentials_api_password');\n                    var reloadurl  = '{$url}';\n                    var encoded = btoa(api_password.value);\n                    new Ajax.Request(reloadurl, {\n                        method: 'post',\n                        parameters: {'api_username' : api_user.value, 'api_password' : encoded},\n                        onComplete: function(transport) {\n                            Element.hide('loadingmask');\n                            if(transport.responseText == '\"Credentials Valid.\"'){\n                                api_user.setStyle({\n                                    fontWeight: 'bold',\n                                    color:  'green' ,\n                                    background: 'transparent url(\"" . $this->getSkinUrl('images/success_msg_icon.gif') . "\") no-repeat right center'\n                                })\n                            }else{\n                                api_user.setStyle({\n                                    fontWeight: 'bold',\n                                    color:  'red',\n                                    background: 'transparent url(\"" . $this->getSkinUrl('images/error_msg_icon.gif') . "\") no-repeat right center'\n                                });\n\n                            }\n                        }\n                    });\n\n                    return false;\n                }\n\n            </script>\n        ");
     return parent::_getElementHtml($element);
 }