拖拽删除DataGrid中的某一项。

DragManager的学习、使用。
示例：

代码：

<? xml version="1.0" encoding="utf-8" ?>
<!--  http://blog.flexexamples.com/2008/04/16/removing-items-from-a-flex-datagrid-control-using-the-dragmanager-class/  -->
< mx:Application  xmlns:mx ="http://www.adobe.com/2006/mxml"
        layout ="vertical"
        verticalAlign ="middle"
        backgroundColor ="white" >

     < mx:Script >
         <![CDATA[
            import mx.core.IUIComponent;
            import mx.events.DragEvent;
            import mx.managers.DragManager;

            private function image_dragEnter(evt:DragEvent):void {
                var obj:IUIComponent = IUIComponent(evt.currentTarget);
                DragManager.acceptDragDrop(obj);
            }

            private function image_dragDrop(evt:DragEvent):void {
                var item:Object = dataGrid.selectedItem;
                var idx:int = arrColl.getItemIndex(item);
                arrColl.removeItemAt(idx);
            }
         ]]>
     </ mx:Script >

     < mx:ArrayCollection  id ="arrColl" >
         < mx:source >
             < mx:Array >
                 < mx:Object  c1 ="r1.c1"  c2 ="r1.c2"  c3 ="r1.c3"  c4 ="r1.c4" />
                 < mx:Object  c1 ="r2.c1"  c2 ="r2.c2"  c3 ="r2.c3"  c4 ="r2.c4" />
                 < mx:Object  c1 ="r3.c1"  c2 ="r3.c2"  c3 ="r3.c3"  c4 ="r3.c4" />
                 < mx:Object  c1 ="r4.c1"  c2 ="r4.c2"  c3 ="r4.c3"  c4 ="r4.c4" />
                 < mx:Object  c1 ="r5.c1"  c2 ="r5.c2"  c3 ="r5.c3"  c4 ="r5.c4" />
                 < mx:Object  c1 ="r6.c1"  c2 ="r6.c2"  c3 ="r6.c3"  c4 ="r6.c4" />
                 < mx:Object  c1 ="r7.c1"  c2 ="r7.c2"  c3 ="r7.c3"  c4 ="r7.c4" />
                 < mx:Object  c1 ="r8.c1"  c2 ="r8.c2"  c3 ="r8.c3"  c4 ="r8.c4" />
                 < mx:Object  c1 ="r9.c1"  c2 ="r9.c2"  c3 ="r9.c3"  c4 ="r9.c4" />
             </ mx:Array >
         </ mx:source >
     </ mx:ArrayCollection >

     < mx:Panel  title ="Drag DataGrid item over the trash icon to remove item"
            styleName ="opaquePanel" >
         < mx:DataGrid  id ="dataGrid"
                dataProvider =" {arrColl} "
                dragEnabled ="true"
                width ="400"
                rowCount ="6"
                verticalScrollPolicy ="on" >
             < mx:columns >
                 < mx:DataGridColumn  dataField ="c1"
                        headerText ="Column 1"   />
                 < mx:DataGridColumn  dataField ="c2"
                        headerText ="Column 2"   />
                 < mx:DataGridColumn  dataField ="c3"
                        headerText ="Column 3"   />
                 < mx:DataGridColumn  dataField ="c4"
                        headerText ="Column 4"   />
             </ mx:columns >
         </ mx:DataGrid >

         < mx:ControlBar  horizontalAlign ="right" >
             < mx:Image  id ="image"
                    source ="@Embed('assets/iconUninstall.png')"
                    dragDrop ="image_dragDrop(event);"
                    dragEnter ="image_dragEnter(event);"   />
         </ mx:ControlBar >
     </ mx:Panel >

</ mx:Application >