Datagrid and multiple ItemRenderer

Question

What I would like to do and haven't been successful is add a column to a Datagrid at runtime.  Each cell in that column is going to be different based upon user data. The first column is populated based upon a user query then another query (i.e. RESTful query) is made to mashup some data.
I wanted a button (mashup data) to appear in the column enabled if data was available and disabled if data was not available.
I was doing something like this:
My MXML file has this:
        <mx:DataGrid id="dg" dataProvider="{ModelLocator.getInstance().list}" itemClick="itemClickHandler(event)" left="10" right="0" bottom="0" top="50" editable="true" >
            <mx:columns>
                <mx:DataGridColumn headerText="Name" dataField="name" editable="true" />
                 <mx:DataGridColumn headerText="Data" dataField="someData" itemRenderer="ActionButtonItemRenderer" />
            </mx:columns>
        </mx:DataGrid>
ActionButtonItemRenderer.as file:
    public class ActionButtonItemRenderer extends Button
        public function ActionButtonItemRenderer()
            super();
            label = "Show Data";
        override public function set data(value:Object):void {
            if (null == value.myData) {
                label = "";
                this.enabled = false;
        // Handle the search button event.
        override protected function clickHandler(event:MouseEvent):void
            // Code omitted here...
It works but when I use my mouse wheel to scroll through the records the buttons get all hosed up and the enabled buttons become disabled.  It's weird.
Thanks!

Answer 1

You create an ArrayCollection or XMLListCollection and populate it initially with perhaps data that would represent "no data".
Then if your queries return real data, the dataProvider object now "has data".
The itemRenderer does the appropriate thing if there is not is no data.
You don't generate the button in the dataProvider, you just get the label and visible property value etc. from the dataProvider.
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Greg Lafrance - Flex 2 and 3 ACE certified
www.ChikaraDev.com
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