Another quick post…
I was stuck recently with a Flex component that had a List with an itemRenderer. The itemRenderer contained another List with an itemRenderer. Now the problem with this is that the data had unique counts and the lists had variable row heights (variableRowHeight = true). The result was that containers would not dynamically resize enough to display the whole List. In other words, the List was clipped and vertical scroll bars were displayed.
After trying several ways to get it to resize correctly and failing miserably, I extended the List component. As I was doing this, I found another post about an AutoSizingAdvancedDataGrid by the guys at WorkDay in which they had similar issues with the AdvancedDataGrid. Since the AdvancedDataGrid is similar to the List, I only had to make a couple of changes to get it working with the List component.
Finally able to post the code: