Flexible buffered data
You could do a couple of different things.
1) use states - have the state of the loading data after the data has been received, processed, etc. switch to a state with newly added states. (I would not recommend this approach though, since it is a bit of a hack. You can use this approach and use a viewstack or something similar, it should be implemented as states (i.e., once the data is processed, go from view index 0 - 1 - 0 is loading state and 1 is visual components)
2) it would be better to update your interface when you have processed the data. If for some reason the UI doesn't update after adding / modifying some UI components, you need to understand things like invalidateProperties and invalidateDisplayList. I found this example very good for understanding these technologies. http://www.quietlyscheming.com/blog/components/randomwalk-component/ and http://demo.quietlyscheming.com/RandomWalk/IconWalk.html
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