When you set Object/Collection as a source for an AdvancedDataGrid to display the source in a Hierarchical manner, the AdvancedDataGrid.dataProvider will return an instance of IHierarchicalCollectionView because internally the source is used to construct a HierarchicalCollectionView which is returned via the dataProvider property.
What if, you want the original source from this IHierarchicalCollectionView. Well, there are some API’s for achieving this –
// First, get the HierarchicalData used to create the HierarchicalCollection
var hd:IHierarchicalData = IHierarchicalCollectionView(adg.dataProvider).source;
//From the HierarchicalData, get the source collection/object
var source:Object = hd.getRoot();