How do I customize the appearance of a Spark DataGrid?
Create custom item renderers to control the display of the cells of the Spark DataGrid control. You can also create custom item renderers for the header cells of each column of the grid.
You set a custom renderer or editor for each column of the grid. Use the GridColumn.itemRenderer, GridColumn.itemEditor, and GridColumn.headerRenderer properties to specify your custom renderer or editor.
You typically create custom item renderers and item editors in MXML. However, for the highest performance, create them in ActionScript.
You can see complete examples here: http://help.adobe.com/en_US/flex/using/WS0ab2a460655f2dc3-427f401412c60d04dca-7ff3.html
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