We're still working to figure out when built-in drag and drop support for Lists will be added. It's currently out of scope for 4.0 but we're trying to find ways to get it in.
When you say built-in , we can still implement our own drag and drop right? (even it is really difficult) (with drag proxy and everything )
btw, i am little surprised that the drag and drop is out of the scope for 4.0, since the use case is very common and the existing drag and drop approach is problematic. I though Gumbo will improve if not invent the wheel again since i saw a lot existing components rewritten.
Existing problematic usage scenarios like "using OS drag and drop , and Flex drag and drop at the same time in Air applications" should be address with this new approach in my opinion.
Good luck with the new drag and drop and hoping that you guys will find a way to put it into 4.0
Yes, you can implement your own. We agree that it's important, something that is out of scope is simply because we think we had other things that were even more important. We do intend for Spark to eventually provide all of the functionality that you needed in Halo, and hopefully improve on the usability of some features as well. But it's a multi-release vision, we won't get everything in the first round.