I'm tackling the concept of creating a local GP service to convert a /local/ KML file to a viewable layer, then viewing the output layer in Flex Viewer (3.3 in use.) I've currently got a GP service built and operating on our ArcGIS server, and it works correctly using ArcMap by way of accepting the input file and generating the output layer for display. I can also generate the correct result by manually browsing to and using the GPDataFile input of the service. If manually added, the resulting map service exists in the FV 3.3 instance. Long story short, I've got the back-end part of this working.
What I'm looking for is a usage example for the ESRI Geoprocessing Widget, that uses the GPDataFile input parameter type. The widget tags reference simply shows the existence of the parameter, and mentions that it should generate a dialog for file upload when used - when I change the GeoprocessingWidget.xml file to include the requisite taskurl/helpurl and the inputparams block, I end up with a 1009 error (null object reference) while the widget tries to initialize. I don't get any dialog popup for selecting the source file.
I've verified spelling & case on all the references, and a different GP service I created for another instance of the Geoprocessing Widget does work, so I know this is at least partially an error in how I'm configuring the XML.
Here's a snippet showing how I'm configuring the input parameter:
label="Input KML File"
It's frustrating that the tag is referenced in the help, but there's not a usage example for it in the manner of the other input parameter types!