兑现AdvancedDataGrid全选功能

实现AdvancedDataGrid全选功能
AdvancedDataGrid功能强大，非常好用。遗憾的是AdvancedDataGrid对全选的支持不是很好。以下代码实现了AdvancedDataGrid的全选功能
1. 左上角加了一个checkBox
2. 每行加了checkBox
3. 不符合条件的不能选
4. 点击全选，选中所有符合条件的记录
抛砖引玉，希望能看到关于AdvancedDataGrid全选的更好的解决方案。

<?xml version="1.0"?><mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" creationComplete="init()"><!--Author: myShareBook.cnDate: 2009-06-29-->    <mx:Script>        <![CDATA[        import mx.controls.Alert;            import mx.collections.ArrayCollection;                        private var selectedColl:ArrayCollection = new ArrayCollection();                        private function init():void{            this.myADG.expandAll();            }                        private function selectAllCbxClick(event:Event):void{            if(selectAllCbx.selected){            this.selectedColl = dpFlat;            this.gc.refresh();            this.myADG.expandAll();            }else{            this.selectedColl = new ArrayCollection();            this.gc.refresh();            this.myADG.expandAll();            }            }                        public function hasSelected(data:Object):Boolean{            var hasSelected:Boolean = false;            for each(var obj:Object in selectedColl){            if(data.Actual == obj.Actual && data.Estimate == obj.Estimate){            hasSelected = true;            break;            }            }            return hasSelected;            }                              [Bindable]            private var dpFlat:ArrayCollection = new ArrayCollection([              {Region:"Southwest", Territory:"Arizona",                   Territory_Rep:"Barbara Jennings", Actual:38865, Estimate:40000},               {Region:"Southwest", Territory:"Arizona",                   Territory_Rep:"Dana Binn", Actual:29885, Estimate:30000},                {Region:"Southwest", Territory:"Central California",                   Territory_Rep:"Joe Smith", Actual:29134, Estimate:30000},                {Region:"Southwest", Territory:"Nevada",                   Territory_Rep:"Bethany Pittman", Actual:52888, Estimate:45000},                {Region:"Southwest", Territory:"Northern California",                   Territory_Rep:"Lauren Ipsum", Actual:38805, Estimate:40000},               {Region:"Southwest", Territory:"Northern California",                   Territory_Rep:"T.R. Smith", Actual:55498, Estimate:40000},                {Region:"Southwest", Territory:"Southern California",                   Territory_Rep:"Alice Treu", Actual:44985, Estimate:45000},               {Region:"Southwest", Territory:"Southern California",                   Territory_Rep:"Jane Grove", Actual:44913, Estimate:45000}            ]);                    ]]>    </mx:Script>    <mx:Panel title="AdvancedDataGrid Control Example"        height="75%" width="75%" layout="horizontal"        paddingTop="10" paddingBottom="10" paddingLeft="10" paddingRight="10"><mx:Canvas width="100%" height="100%">        <mx:AdvancedDataGrid id="myADG"             width="100%" height="100%"             initialize="gc.refresh();">                    <mx:dataProvider>                <mx:GroupingCollection id="gc" source="{dpFlat}">                    <mx:grouping>                        <mx:Grouping>                            <mx:GroupingField name="Region"/>                            <mx:GroupingField name="Territory"/>                        </mx:Grouping>                    </mx:grouping>                </mx:GroupingCollection>            </mx:dataProvider>                                <mx:columns>                <mx:AdvancedDataGridColumn>                <mx:itemRenderer>                <mx:Component>                <mx:HBox width="100%" horizontalAlign="center">                <mx:CheckBox selected="{data.Actual > 40000 &amp;&amp; outerDocument.hasSelected(data)}"                enabled="{data.Actual > 40000}" />                <mx:Text text="{data.Region}"/>                </mx:HBox>                </mx:Component>                </mx:itemRenderer>                </mx:AdvancedDataGridColumn>                <mx:AdvancedDataGridColumn dataField="Territory"/>                <mx:AdvancedDataGridColumn dataField="Territory_Rep"                    headerText="Territory Rep"/>                <mx:AdvancedDataGridColumn dataField="Actual"/>                <mx:AdvancedDataGridColumn dataField="Estimate"/>            </mx:columns>       </mx:AdvancedDataGrid>       <mx:CheckBox id="selectAllCbx" toolTip="Select All" click="selectAllCbxClick(event)"/>       </mx:Canvas>    </mx:Panel>    </mx:Application>