This post (http://www.inductiveautomation.com/forum/viewtopic.php?f=23&t=2716&p=3623#p3623) shows how to use an expression and script to protect against running code when no item is selected in a drop down list. Along these lines, I have a dynamic property bound to the selected value - the property is an SQL query with the WHERE clause coming from the list selection. Can anyone point me in the direction of protecting this property from executing if nothing is selected? The property binding is binding types -> Database -> SQL Query. Where would I put suitable if/then statements for protection?
Also, the script playground is a nice feature. How can I access objects on my pages (like with event.source… etc)? I would use the tool more if I could get access to my datasets and such that I already have set up.