protected function fieldConditionMet(FieldInterface $field, array $results)
    {
        $conditions = [];

        foreach ($field->getCondition() as $field_name => $condition) {
            $value = $condition['value'];
            $operation = $condition['operation'];

            $field_value = $this->getFieldValue($field_name, $results);

            if (is_array($field_value)
                && key_exists($field_name, $field_value)) {
                $field_value = $field_value[$field_name];
            }

            switch ($operation) {
                case "!=":
                    $conditions[] = $field_value != $value;
                    break;

                case '=':
                default:
                    $conditions[] = $field_value == $value;
                    break;
            }
        }
        $conditions = array_unique($conditions);

        return count($conditions) === 1 ? reset($conditions) : false;
    }