/**
  * Get form fields for processing a payment
  */
 public function getFormFields()
 {
     $fieldList = parent::getFormFields();
     $amountField = $fieldList->fieldByName('Amount');
     $amountField->setValue('99.00');
     $fieldList->replaceField('Amount', $amountField);
     $fieldList->merge($this->getCreditCardFields());
     return $fieldList;
 }
 /**
  * Get the form requirements
  * @return {RequiredFields}
  */
 public function getFormRequirements()
 {
     $required = parent::getFormRequirements();
     $required->appendRequiredFields(new RequiredFields('BillingAddress', 'BillingCity', 'BillingState', 'BillingZIPCode', 'BillingCountry'));
     return $required;
 }