I bet that is correct. I have found that it is best to use callLater for any control manipulation if I have just modified the dataProvider.
But, Roger, don't guess. Debug the code to find out which line is producing the error. If you don't have good debugging techniques, develop them now. Tracy ________________________________ From: flexcoders@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Clint Tredway Sent: Thursday, January 25, 2007 12:07 PM To: flexcoders@yahoogroups.com Subject: Re: [flexcoders] Cannot access a property or method of a null object reference most likely the setting of the selectedIndex is what is causing that error. Its trying to set a property to a component that doesnt exist yet. On 1/25/07, Roger Ross <[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]> > wrote: Hello, Working my way throught the "Training From the Source" turorial and ran into this error message. Not sure why I am getting it. I compared my code to the completed code for the lesson and it looks the same with no problems when I compile it. TypeError: Error #1009: Cannot access a property or method of a null object reference. at Dashboard/::catHandler() at Dashboard/__catRPC_result() at flash.events::EventDispatcher/flash.events:EventDispatcher::dispatchEven tFunction() at flash.events::EventDispatcher/dispatchEvent() at mx.rpc.http.mxml::HTTPService/http://www.adobe.com/2006/flex/mx/internal ::dispatchRpcEvent <http://www.adobe.com/2006/flex/mx/internal::dispatchRpcEvent> () at mx.rpc::AbstractInvoker/http://www.adobe.com/2006/flex/mx/internal::resu ltHandler <http://www.adobe.com/2006/flex/mx/internal::resultHandler> () at mx.rpc::Responder/result() at mx.rpc::AsyncRequest/acknowledge() at ::DirectHTTPMessageResponder/completeHandler() at flash.events::EventDispatcher/flash.events:EventDispatcher::dispatchEven tFunction() at flash.events::EventDispatcher/dispatchEvent() at flash.net::URLLoader/flash.net:URLLoader::onComplete() Here is a copy of the code that it has me write with the comboBox that is to receive the data: <?xml version="1.0" encoding="utf-8"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml <http://www.adobe.com/2006/mxml> " layout="horizontal" creationComplete="catRPC.send()"> <mx:Script> <![CDATA[ import mx.collections.ArrayCollection; import mx.rpc.events.ResultEvent; [Bindable] private var categories:ArrayCollection=new ArrayCollection(); private function catHandler(event:ResultEvent):void{ categories = event.result.catelog.category; var catObj:Object = new Object(); catObj.name = "All"; catObj.categoryID = 0; categories.addItemAt(catObj, 0); catCombo.selectedIndex = 0; } ]]> </mx:Script> <mx:HTTPService id="catRPC" url="http://www.flexgrocer.com/category.xml <http://www.flexgrocer.com/category.xml> " result="catHandler(event)"/> <mx:ComboBox id="catCombo" dataProvider="{categories}" labelField="name"/> Any Idea's... Thanks, Roger -- http://indeegrumpee.spaces.live.com/ <http://indeegrumpee.spaces.live.com/>
