Hi Jiali,
Thanks for using Syncfusion Products.
Sparkline control feature is not available in 8.4.0.10 version. It will available from the version 9.2.0.137, We suggest you to upgrade to latest version . Please find the download link for latest version.
http://www.syncfusion.com/downloads/latest-version
Please let us know your concerns.
Regards,
Siva