public function setAsset($url, $fileType)
    {
        $this->assetUrl = $url;
        $this->assetFileType = $fileType;
        return $this;
    }
public function setAsset($url, $fileType)
    {
        $this->assetUrl = $url;
        $this->assetFileType = $fileType;
        return $this;
    }
public function setAsset ( $ url , $ fileType ) { $ this -> assetUrl = $ url ; $ this -> assetFileType = $ fileType ; return $ this ; }
Set a content url for rich notifications.

This is only available on devices running iOS 10 or higher.

@param string $url
@param string $fileType

@return AppleMessageBuilder
Set a content url for rich notifications .