I want to create two custom work item controls. Each control will be a drop down list box. In the InvalidateDatasource() method of Control1, I retrieve information from a database, populate the drop down list box, check to see if a value has already been selected for the list box, and if so, set the list box equal to that value. I've got this working (which is pretty cool!).

Now, based on the contents of the first drop down list box, I want to filter what contents are in the second drop down list box, called Control2 (picture Control1 being a list of states, and Control2 being a list of cities, specific to which state is selected in Control1). How do I, from Control1.InvalidateDatasource(), trigger Control2.InvalidateDatasource()?

Control2.InvalidateDatasource() was where I was going to put the code to populate Control2 appropriately?

Control1 and Control2 are both user controls in the same assembly.

Does that make any sense, or do I need to provide more details?

Mickey, you are right on where to put code to populate control2. When user selects a value in control1, set the value in associated field in WorkItem object, which then will trigger FieldChangedEvent and then the form will raise Invalidate for all controls. In summary, you need to set the associated field value when user selects an item in control1, and then you should get Invalidate on Control2.

BTW, you are the first one I know of who successfully used the custom controls feature. I heard couple of people not getting their dlls updated with SP1 setup. Did you have any problems or hickups getting up this far?

Thanks.

Hey Naren!

It doesn't quite seem to work.  When the user selects a value in Control1, it triggers the InvalidateDatasource() method for Control1 and Control1 only. It triggers the method because I invoke it from the SelectIndexChanged event of Control1).   Now the work item is marked as changed.  When I save the work item, it then triggers the InvalidateDatasource() method for Control2.  But what I want is, when the value is selected in Control1, for the InvalidateDatasource() to trigger for Control2.  I don't mind if InvalidateDatasource() is raised for all controls.  But currently it only happens on the Save, not when something is selected from the list box.

I didn't have any hiccups installing SP1.  It took a couple of changes on your example on your blog to get it running, but nothing major.  Let me get past this problem, and I'll go into some detail on what I did.

Any suggestions?

Thanks!

Mickey G.