using outerDocument in flex

[Amirtharaj Chinnaraj]

hi iam a new to flex

by searching some forums i came to that we can use outerDocument keyword to acess the variable define outside the componet in an mxml
but in below code iam getting flash error because of the line 13

   <mx:DataGrid id="myGrid" dataProvider="{initDG}"
          variableRowHeight="true">  
        <mx:columns>
          <mx:DataGridColumn dataField="Artist"/>
          <mx:DataGridColumn dataField="Album"/>
          <mx:DataGridColumn dataField="Cover">
            <mx:itemRenderer>
              <mx:Component>
                <mx:VBox>
                  <mx:Script>
                    <![CDATA[            
                      // Variable in the renderer scope.
                    [b]  public var localVar:String=outerDocument.localVar+"amir ";       [/b]
                    ]]>
                  </mx:Script>
    
                  <mx:Text id="albumName" width="100%" selectable="false" text="{data.Album}"/>
                  <mx:Image id="albumImage" height="45" source="{data.Cover}"/>
                  <mx:TextArea text="{'Renderer localVar= ' + localVar}"/>
                  <mx:TextArea text="{'App localVar= ' + outerDocument.localVar}"/>
                </mx:VBox>
              </mx:Component>
            </mx:itemRenderer>
          </mx:DataGridColumn>    
          <mx:DataGridColumn dataField="Price"/>
        </mx:columns>     
      </mx:DataGrid>       

please advice me on this

also please tell is it possible to acess the methods declered outside the <mx:component> using outerDocument keyword