After some googling, this seems to be an existing issue with Tree refreshes and I haven't been able to find a good workaround.
The issue can be repro'ed at one of Adobe's quickstart demo page: http://www.adobe.com/devnet/flex/quickstart/working_with_tree/ Go to the last example, and expand all nodes in the tree on the left. Height doesn't exceed the container, so no scrollbar. Now drag elements from the right to the tree to insert them. When the height of tree extends beyond the container, no v-scrollbar is shown. But a scrollbar is shown after you collapse/expand the tree. Invalidating the tree's list/properties/displaylist didn't seem to cause a refresh. The underlying collection still returns old length when Tree processes configureScrollBars(). Can anyone suggest a good workaround? (aside from reassigning dataProvider, since that's too expensive for me.) A couple of old flexcoder threads also talks about this problem: http://tech.groups.yahoo.com/group/flexcoders/message/46541 http://tech.groups.yahoo.com/group/flexcoders/message/37627 Thanks!
