Flex Spark组件实现错误

    <s:DataGrid includeIn=\"admin\" x=\"150\" y=\"288\" requestedRowCount=\"4\">
    <s:columns>
        <s:ArrayList>
            <s:GridColumn dataField=\"dataField1\" headerText=\"Column 1\"></s:GridColumn>
            <s:GridColumn dataField=\"dataField2\" headerText=\"Column 2\"></s:GridColumn>
            <s:GridColumn dataField=\"dataField3\" headerText=\"Column 3\"></s:GridColumn>
        </s:ArrayList>
    </s:columns>
    <s:typicalItem>
        <fx:Object dataField1=\"Sample Data\" dataField2=\"Sample Data\" dataField3=\"Sample Data\"></fx:Object>
    </s:typicalItem>
    <s:ArrayList>
        <fx:Object dataField1=\"data1\" dataField2=\"data1\" dataField3=\"data1\"></fx:Object>
        <fx:Object dataField1=\"data2\" dataField2=\"data2\" dataField3=\"data2\"></fx:Object>
        <fx:Object dataField1=\"data3\" dataField2=\"data3\" dataField3=\"data3\"></fx:Object>
        <fx:Object dataField1=\"data4\" dataField2=\"data4\" dataField3=\"data4\"></fx:Object>
    </s:ArrayList>
</s:DataGrid>

Could not resolve <s:DataGrid> to a component implementation.