omgdef\multilingual\MultilingualBehavior::attach PHP Method

    public function attach($owner)
    {
        /** @var ActiveRecord $owner */
        parent::attach($owner);
        if (empty($this->languages) || !is_array($this->languages)) {
            throw new InvalidConfigException('Please specify array of available languages for the ' . get_class($this) . ' in the ' . get_class($this->owner) . ' or in the application parameters', 101);
        }
        if (array_values($this->languages) !== $this->languages) {
            //associative array
            $this->languages = array_keys($this->languages);
        }
        $this->languages = array_unique(array_map(function ($language) {
            return $this->getLanguageBaseName($language);
        }, $this->languages));
        if (!$this->defaultLanguage) {
            $this->defaultLanguage = isset(Yii::$app->params['defaultLanguage']) && Yii::$app->params['defaultLanguage'] ? Yii::$app->params['defaultLanguage'] : Yii::$app->language;
        }
        $this->defaultLanguage = $this->getLanguageBaseName($this->defaultLanguage);
        if (!$this->currentLanguage) {
            $this->currentLanguage = $this->getLanguageBaseName(Yii::$app->language);
        }
        if (empty($this->attributes) || !is_array($this->attributes)) {
            throw new InvalidConfigException('Please specify multilingual attributes for the ' . get_class($this) . ' in the ' . get_class($this->owner), 103);
        }
        if (!$this->langClassName) {
            $this->langClassName = get_class($this->owner) . $this->langClassSuffix;
        }
        $this->langClassShortName = $this->getShortClassName($this->langClassName);
        $this->ownerClassName = get_class($this->owner);
        $this->ownerClassShortName = $this->getShortClassName($this->ownerClassName);
        /** @var ActiveRecord $className */
        $className = $this->ownerClassName;
        $this->ownerPrimaryKey = $className::primaryKey()[0];
        if (!isset($this->langForeignKey)) {
            throw new InvalidConfigException('Please specify langForeignKey for the ' . get_class($this) . ' in the ' . get_class($this->owner), 105);
        }
        $rules = $owner->rules();
        $validators = $owner->getValidators();
        foreach ($rules as $rule) {
            if (in_array($rule[1], $this->excludedValidators)) {
                continue;
            }
            $rule_attributes = is_array($rule[0]) ? $rule[0] : [$rule[0]];
            $attributes = array_intersect($this->attributes, $rule_attributes);
            if (empty($attributes)) {
                continue;
            }
            $rule_attributes = [];
            foreach ($attributes as $key => $attribute) {
                foreach ($this->languages as $language) {
                    if ($language != $this->defaultLanguage) {
                        $rule_attributes[] = $this->getAttributeName($attribute, $language);
                    }
                }
            }
            if (isset($rule['skipOnEmpty']) && !$rule['skipOnEmpty']) {
                $rule['skipOnEmpty'] = !$this->requireTranslations;
            }
            $params = array_slice($rule, 2);
            if ($rule[1] !== 'required' || $this->requireTranslations) {
                $validators[] = Validator::createValidator($rule[1], $owner, $rule_attributes, $params);
            } elseif ($rule[1] === 'required') {
                $validators[] = Validator::createValidator('safe', $owner, $rule_attributes, $params);
            }
        }
        if ($this->dynamicLangClass) {
            $this->createLangClass();
        }
        $translation = new $this->langClassName();
        foreach ($this->languages as $lang) {
            foreach ($this->attributes as $attribute) {
                $attributeName = $this->localizedPrefix . $attribute;
                $this->setLangAttribute($this->getAttributeName($attribute, $lang), $translation->{$attributeName});
                if ($lang == $this->defaultLanguage) {
                    $this->setLangAttribute($attribute, $translation->{$attributeName});
                }
            }
        }
    }