Flex拖拽形成柱状图

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" horizontalAlign="center" layout="vertical" creationComplete="init()">
<mx:Script>
    <![CDATA[
        import mx.controls.Alert;
        import mx.controls.DataGrid;
        import mx.events.DragEvent;
        import mx.core.UIComponent;
        import mx.managers.DragManager;
        import mx.core.DragSource;
        import mx.collections.ArrayCollection;
        
        //DataGrid的数据源
        [Bindable]
        private var medalsAC:ArrayCollection = new ArrayCollection( [
            { Country: "USA", Gold: 35, Silver:39, Bronze: 29 },
            { Country: "China", Gold: 32, Silver:17, Bronze: 14 },
            { Country: "Russia", Gold: 27, Silver:27, Bronze: 38 } ]);
            
        //ColumnChart的数据源, 默认为空    
        [Bindable]
        private var chartData:ArrayCollection = new ArrayCollection()
        
        private function init():void{
            
            //让columnChart监听拖拽事件      
            column.addEventListener(DragEvent.DRAG_ENTER,dragEnterHandle)
            column.addEventListener(DragEvent.DRAG_DROP,dragdropHandle)
        }
        
        //因为只有DataGrid推拽，所以直接允许，如果界面上有多个控件监听拖拽事件，需要判断后允许正确的数据进入
        private function dragEnterHandle(e:DragEvent):void{
            DragManager.acceptDragDrop(e.currentTarget as UIComponent)
        }
        
        //拖拽放开后处理
        private function dragdropHandle(e:DragEvent):void{
            //如果Column Chart中已经存在相同数据，报错返回
            if(chartData.contains((e.dragInitiator as DataGrid).selectedItem)){
                Alert.show("数据已经存在");
                return;
            }
            //往column chart的dataprovider中添加拖拽数据。
            //如果只需要特定的数据进入column chart，可以先做数据筛选。
            chartData.addItem((e.dragInitiator as DataGrid).selectedItem)
        }
        
        
            

    ]]>
</mx:Script>

<!--允许Grid拖拽数据-->
<mx:DataGrid dragEnabled="true" dataProvider="{medalsAC}" >
<mx:columns>
    
    <mx:DataGridColumn dataField="Country" />
    <mx:DataGridColumn dataField="Gold" />
    <mx:DataGridColumn dataField="Silver" />
    <mx:DataGridColumn dataField="Bronze" />
        
</mx:columns>
    
</mx:DataGrid>

 <!-- 定义颜色 -->
    <mx:SolidColor id="sc1" color="yellow" alpha=".8"/>
    <mx:SolidColor id="sc2" color="0xCCCCCC" alpha=".6"/>
    <mx:SolidColor id="sc3" color="0xFFCC66" alpha=".6"/>

<!-- 定义颜色 -->
    <mx:Stroke id="s1" color="yellow" weight="2"/>
    <mx:Stroke id="s2" color="0xCCCCCC" weight="2"/>
    <mx:Stroke id="s3" color="0xFFCC66" weight="2"/>

<!--Column chart设置成能解析Country: "Russia", Gold: 27, Silver:27, Bronze: 38这样的数据项-->
<mx:ColumnChart id="column"
            height="200"
            width="300"
            paddingLeft="5"
            paddingRight="5"
            showDataTips="true"
            dataProvider="{chartData}"
        >                
            <mx:horizontalAxis>
                <mx:CategoryAxis categoryField="Country"/>
            </mx:horizontalAxis>
            <mx:series>
                <mx:ColumnSeries
                    xField="Country"
                    yField="Gold"
                    displayName="Gold"
                    fill="{sc1}"
                    stroke="{s1}"
                />
                <mx:ColumnSeries
                    xField="Country"
                    yField="Silver"
                    displayName="Silver"
                    fill="{sc2}"
                    stroke="{s2}"
                />
                <mx:ColumnSeries
                    xField="Country"
                    yField="Bronze"
                    displayName="Bronze"
                    fill="{sc3}"
                    stroke="{s3}"
                />
            </mx:series>
        </mx:ColumnChart>
    
</mx:Application>