Flex tooltip on spark datagrid header

Is it possible to set开发者_开发百科 a tooltip just on the header of a spark datagrid. I do not want any tooltips on the data - just the header. I have played with mouse over and this sort of looks like it might work. This seems a bit of a hack to me though.

Can anyone help or give me any tips (pun intended)?

Thanks

you should have to:

1. create a custom spark datagrid skin...
2. create a headerRenderer skin wich extends the GridItemRenderer and put it into th spark datagrid skin
3. add a tooltip to the label "labelDispaly"

it should work...

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" 
               xmlns:s="library://ns.adobe.com/flex/spark" 
               xmlns:mx="library://ns.adobe.com/flex/mx" 
               minWidth="955" minHeight="600">
    <fx:Script>
        <![CDATA[
            import mx.collections.ArrayCollection;
            import mx.controls.Alert;

            import spark.components.Grid;

            [Bindable]private var collection:ArrayCollection = new ArrayCollection([
                {field01:"field01", content:"your content", field02:"field02"},
                {field01:"field01", content:"your content your content your content your content", field02:"field02"},
                {field01:"field01", content:"your content your content your content your content", field02:"field02"}
            ]);



        ]]>
    </fx:Script>
    <fx:Script>
        <![CDATA[       
            import mx.collections.ArrayCollection;          
            import mx.controls.Alert;   
            import spark.events.GridEvent;          
            import spark.components.Image;


            [Bindable]
            private var myArrivalShips:ArrayCollection = new ArrayCollection([
                {arrivalShipsName:"Ship A", ETD:"12 March"},
                {arrivalShipsName:"Ship B", ETD:"25 March"}             
            ]); 

            private function buildToolTip(item:Object,column:GridColumn):String{
                var myString:String = "";

                if(column.columnIndex==0){
                    myString=myString+"Arrival Ships";
                }
                else if(column.columnIndex==1){
                    myString=myString+"ETD";
                }
                return myString;
            }


        ]]>
    </fx:Script>
    <s:BorderContainer x="267" y="11" width="331" height="586">

        <s:DataGrid id="arrivalTable" x="10" y="326" width="302" height="205" requestedRowCount="4" dataProvider="{myArrivalShips}" showDataTips="true" dataTipFunction="buildToolTip">
            <s:columns>
                <s:ArrayList>
                    <s:GridColumn dataField="arrivalShipsName" headerText="Arrival Ships"></s:GridColumn>
                    <s:GridColumn dataField="ETD" headerText="ETD"></s:GridColumn>              
                </s:ArrayList>
            </s:columns>            

        </s:DataGrid>
        <s:BorderContainer x="10" y="19" width="302" height="285">
        </s:BorderContainer>

    </s:BorderContainer>

</s:Application>