[flexcoders] Updating DataGrid Item with Tomcat

[Alex Birch]

The DataGrid is so amazing. I may be abusing it, yet I would like to display
information to a user and let them update information. Ideally, I could call
a Servlet on a Tomcat server.

My question is how can I tell which DataRows have been updated by the user.
My hackneyed approach has been to try and clone a version of the original
data, then I was going to compare the data before calling a httpservice.
Unfortunately I haven't found a nice deep copy method to copy an array.

Any pointer to an example for updating an editable datagrid, then calling a
servlet (I've found many with the RemoteObject.)

Here is an example below.

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"; layout="absolute"
initialize="initApp()">
    <mx:Script>
        <![CDATA[
            import mx.rpc.events.ResultEvent;
            import mx.collections.ICollectionView;
        public var unmodifiedDataProvider:Object = null;
        [Bindable]
        private var modifiableDataProvider:mx.collections.ICollectionView =
null;

        private function initApp():void{
            this.statesHttpService.send();
        }

         private function stateModelResult(event:ResultEvent):void {
                 try{
                     modifiableDataProvider = event.result.Requests.Request;
                     unmodifiedDataProvider = new Object();
                 for (var i:int = 0; i < modifiableDataProvider.length; i++)
                   {
                    unmodifiedDataProvider[i] =
modifiableDataProvider[i].valueOf();
                    //Any deep copy method would be immeasurably appreciated
                   }
                 }
                 catch (err:Error)
                 {
                     unmodifiedDataProvider = null;
                     modifiableDataProvider = null;
                     this.updateLinkButton.enabled = false;

                 }
        }

        private function updateInformation():void {
          var object:Object;


          for (var i:int = 0; i < modifiableDataProvider.length; i++)
          {
              object = modifiableDataProvider[i];
          }
      }
        ]]>

    </mx:Script>
    <mx:HTTPService id="statesHttpService" method="get"  url="
http://www.lifesabirch.org/target.xml";   result="stateModelResult(event)" />
     <mx:LinkButton x="463" y="85" id="updateLinkButton" label="Update"
click="updateInformation()"/>

    <mx:DataGrid x="66" y="115" id="requestDataGrid"
dataProvider="{modifiableDataProvider}" width="95%" height="95%"
editable="true">
   <mx:columns>
        <mx:DataGridColumn dataField="RequestID" headerText="Order Number"
editable="false" />
        <mx:DataGridColumn dataField="Target" headerText="Target"
itemEditor="mx.controls.TextInput" editorDataField="text" editable="true" />
        <mx:DataGridColumn dataField="Comments" headerText="Comments"
itemEditor="mx.controls.TextInput" editorDataField="text" editable="true" />
   </mx:columns>
   </mx:DataGrid>
</mx:Application>


-- 
~~
http://www.lifesabirch.org