Flex 4 AdvancedDataGrid with 3-State Checkbox

We are looking for a Flex 4 AdvancedDataGrid that supports 3 state check boxes in both the header and within the column. Our AdvancedDataGrid displays hierarchical data that is limited to a single branch depth. We would also like the parents nodes to support 3 state check boxes as well. When parent node is open, child node check boxes should be indented. Spark Item Renders preferred. Performance must be snappy. Deliverables: -Actionscript 3 files that include item renders and/or AdvancedDataGrid Extended Class ## Deliverables We are including two screenshots of mocked up AdvancedDataGrids. One shows the parent node in a 'checked state', and another shows the parent node in the 'indeterminate state.'