Howto add date range parameters to linechart?

I'm using SQL Server 2014 and SSDT 12. I have a linechart generated using three fields - FCP, NFS (both integers) and TimeIndex (the datetime over 30 days).

I see how to add parameters but how do I allow users to specify a date range? For example to only view data from 01/12/2014 - 07/12/2014.

Thanks in advance
Adam