Selecting a Unique value in a DFWP dropdown menu + passing it as a Query Param

To create a drop down menu with unique list values you must use xslt filtering on the row selection.



Idea applied from here - http://social.msdn.microsoft.com/forums/en-US/sharepointcustomization/thread/9b2464fc-1255-431e-8976-f4c9e44ec256/
Source quoted in that post here - http://blogs.msdn.com/timpash/archive/2005/11/23/XPATH-Filtering-Distinct-Values.aspx


Now that unique values are assured and we have nice drop down values. A change or selection listener has to be created.

I used the following resources to learn how to do this. Key take away the value has to be set for the selection. For what every reason Microsoft chose not to set it.

5 out of 5 - http://social.msdn.microsoft.com/Forums/en-US/sharepointcustomization/thread/584a94dc-9f44-4dee-8e95-7d47fe8fcee5
Related in depth explanation 6 of 5 J - http://mdasblog.wordpress.com/2008/01/03/firing-an-event-when-a-user-selects-a-value-from-a-data-view-web-part-dropdown/
Another resource I reviewed: http://social.msdn.microsoft.com/Forums/en/sharepointcustomization/thread/b75dcf23-a5de-4f1a-ba70-fccf44989bd7

Don’t forget to check if your user has made a selection. :)

Now that the change listener has been added a parameter can be added to manipulate another DFWP as desired.

Another good link - http://blogs.msdn.com/frontpoint/archive/2005/02/08/369249.aspx