I have used the logic from Spark Tree to build AdvancedDataGrid based on Spark DataGrid and it seem to work nice:
Since AdvancedDataGridcontains a few code and uses a lot of Spark Tree logic I’ve decided to add it to the Spark Tree project in GitHub.com instead of creating a separate library.
Note: you will not see disclosure icons unless you specify corresponding item renderer for some column: <s:GridColumn itemRenderer="com.sparkTree.DefaultTreeADGItemRenderer"/>
Download SparkTree4.5.swc for Flex SDK 4.5 and higher.
Please report bugs in comments or to the GitHub Issue Tracker.
[...] there is currently no official Spark AdvancedDataGrid, Maxim Kachurovskiy has created his own custom Spark AdvancedDataGrid/ which he has added to the Spark Tree project on [...]
Great stuff, man, thanks for sharing it !