C# - Parameters Programaticaly For GridView Select Query?

I am trying to show a Gridview that lists information in a database based on a query. The query takes a parameter of a string, how do you define what this parameter is. An example of the screen I am stuck at is:http://static.asp.net/asp.net/images/dataaccess/07fig08cs.pngAn example of the code i want to use is:parameter for my object data source select query = OBDS_Query_ParameterOBDS_Query_Parameter = str;

Sorry Im not sure how to explain it...For instance if I have a query that GetAllProducts(String userName); How do i pass or define what userName is when using the data gridview. I am using an Object DataSource and linking the data Gridview to that. I can do this without the object data source and strictly melodramatically like this:

quartz_SongsTableAdapter songsAdapter = new quartz_SongsTableAdapter();
CurrentRole = "admin";
GridView1.DataSource = songsAdapter.GetSongForClient(CurrentRole);
GridView1.DataBind();