components/behaviors/ImageBehavior.php
public function init()
    {

        if (!$this->attribute) {
            throw new InvalidConfigException(Yii::t('wavecms/main', 'Property "attribute" is not defined in ImageBehavior'));
        }

        if (!is_array($this->sizes)) {
            throw new InvalidConfigException(Yii::t('wavecms/main', 'Property "sizes" is not defined in ImageBehavior'));
        }

        parent::init();
    }
public function init()
    {

        if (!$this->attribute) {
            throw new InvalidConfigException(Yii::t('wavecms/main', 'Property "attribute" is not defined in ImageBehavior'));
        }

        if (!is_array($this->sizes)) {
            throw new InvalidConfigException(Yii::t('wavecms/main', 'Property "sizes" is not defined in ImageBehavior'));
        }

        parent::init();
    }
Init function
@inheritdoc
@throws InvalidConfigException