code: public function init()
      {
          parent::init();
  
          if ($this->model === null) {
              throw new InvalidConfigException('Please specify the "model" property.');
          }
          if ($this->formatter === null) {
              $this->formatter = Yii::$app->getFormatter();
          } elseif (is_array($this->formatter)) {
              $this->formatter = Yii::createObject($this->formatter);
          }
          if (!$this->formatter instanceof Formatter) {
              throw new InvalidConfigException('The "formatter" property must be either a Format object or a configuration array.');
          }
          $this->normalizeAttributes();
  
          if (!isset($this->options['id'])) {
              $this->options['id'] = $this->getId();
          }
      }
docs: Initializes the detail view.
  This method will initialize required property values.