BIRT dynamic image url - cannot get access to data columns

I am trying to display diffe开发者_运维技巧rent images based on data returned. I am running into the following issues

1. DataSet is not available on the image control for me to make decisions based on the column information. I am using a grid layout (no tables)... Think of a letter

2. I tried to create report level variables and assign it the value from dataset during the onFetch event. However, that assignment does not happen.

I have tried both

rptvar = dataSetRow["colname"]
rptvar = Row["colname"]

I have confirmed that onFetch event does get called using Javascript debugging (see http://www.lebirtexpert.com/wordpress/2010/08/)

Please let me know how to access dataset columns to dynamically create the image URI

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There's a post on the BIRT world blog that should be very useful to you: http://birtworld.blogspot.com/2010/09/birt-image-report-item.html

Kudos to Mr. Weathersby!