I add and remove many instances of the class on the display list. I get lots of memory leakage. All my listeners are weakly referenced, I even remove the event listeners when I unload the class instances. I also delete everything I’ve created. Still memory leaks. It turns out, and it took a while to find this, that you need to “unloadAndStop(true)” on images you’ve loaded, then they get unloaded from memory. Now, no memory leaks.

There don’t seem to be many mentions of this, certainly one to watch out for if you’re having memory problems!

We’ve just put our new Twitter application on the Noon programme, getting reaction and questions after the death of Michael Jackson. I’m really excited to have web technology and television graphics working together, it’s something I think we’ll be seeing much more of. Now our presenters in the studio search on Twitter, select the tweets they like, and immediately put them on air from the studio laptop, no outside involvemement necessary. Emails and web texts appear on the app in the same way too. Collaboration is also possible, a producer in the newsroom can filter the Tweets to make the presenter’s job easier. Profanity and url filtering is built in, as well as removal of some of the Twitter tags to make it more presentable on the telly.

I’ve been writing this app for about a month now (ever since Krishnan did ‘Surgery Live‘ – watching the programme and the Twitter feed together felt like a totally new way of doing tv), and it’s finally reached a mature enough stage that we can put it live on air. There’s a slight issue with recovery after loss of network connection that will be fixed in the next day or so – in the meantime the time honoured IT Crowd fix of turning it off and on again works well enough!

I learned a lot about regular expressions during this project, Grant Skinner’s excellent RegExr was invaluable for debugging AS3 regular expressions.

Stay tuned, we’re working on a few other exciting web ideas that will be on the programme soon, Tweet @krishgm (our presenter Krishnan), @martincollett (me), @channel4news or @c4news (the studio)

David has a whole range of sensors on the roof of his house for just about every meteorological value you might imagine, he uploads data to the site every 4 seconds, and you can browse historical trends too. He’s even planning to add a webcam, great work!

Hello from Washington DC, where I’ve been directing our coverage for Channel 4 News and ITV news on Barack Obama’s inauguration day. I was working for most of the time on the roof of the Canadian Embassy, overlooking the Capitol building while the new president was being sworn in.

It was cold, sitting directing for 3 hours at -11C, it took most of the rest of the day to thaw out, but the superb view was great compensation.

Before I came out I (almost) finished off a word / snowcloud generator for Channel 4 News, it’s probably the bit of Flash programming I’m most pleased with, at the moment. Have a play, it indexes the most-used words back into the full text of Barack Obama’s inauguration speech, and lets you watch the video at the same time. I’ll be working on improving the look and feel when I get back to the UK…

<?xml version="1.0" encoding="utf-8"?>
<!--minimal Air example, communication with BlazeDS server database and messaging-->
<!--no extra server config needed inside Flex environment-->
<mx:WindowedApplication
        xmlns:mx="http://www.adobe.com/2006/mxml"
        backgroundColor="#FFFFFF"
        creationComplete="init()" width="837" height="660">
    <mx:Script>
        <![CDATA[
        	import mx.messaging.channels.PollingChannel;
        	import mx.messaging.events.ChannelFaultEvent;
        	import mx.messaging.FlexClient;
        	import mx.rpc.events.FaultEvent;
            import mx.messaging.Channel;
            import mx.messaging.ChannelSet;

            import mx.messaging.channels.AMFChannel;
			import mx.messaging.messages.AsyncMessage;
			import mx.messaging.messages.IMessage;
			import mx.messaging.Consumer;
			import mx.messaging.Producer;
			import mx.messaging.channels.StreamingAMFChannel;
			import mx.messaging.events.MessageEvent;
			import mx.messaging.events.ChannelEvent;
			import mx.messaging.FlexClient;
			import mx.rpc.remoting.RemoteObject;
			import com.carlcalderon.arthropod.Debug;			

			private var producer:Producer = new Producer();
            private var consumer:Consumer = new Consumer();
            private var blazeUrl:String = "http://192.168.1.201:8400/samples/messagebroker/"; //url of turnkey BlazeDS installation
            [Bindable]
			private var ro1:RemoteObject = new RemoteObject();
			private var ro2:RemoteObject = new RemoteObject();

            public function init():void
            {
            	Debug.clear();
	           	ro1.addEventListener(FaultEvent.FAULT, logFault);
            	ro2.addEventListener(FaultEvent.FAULT, logFault);

            	//config db...
                var cs:ChannelSet = new ChannelSet();
                var customChannel:Channel = new AMFChannel("my-amf", blazeUrl + "amf");
                cs.addChannel(customChannel);
                ro1.channelSet = cs;
                ro1.destination = "product";

                //config messages
                ro2.channelSet = cs; //same address as database
                //ro2.destination = "chat-room-service"; //this line not needed, why not?? (maybe defaults...)
                var myStreamingAMF:StreamingAMFChannel = new StreamingAMFChannel("my-streaming-amf", blazeUrl + "streamingamf");
				var myPollingAMF:AMFChannel = new AMFChannel("my-polling-amf", blazeUrl + "amfpolling");
				myPollingAMF.pollingEnabled = true;
				myPollingAMF.pollingInterval = 5000; //set long, so we can see when polling kicks in

				//next line from http://www.dcooper.org/Blog/client/index.cfm?mode=entry&amp;amp;amp;amp;amp;entry=8E1439AD-4E22-1671-58710DD528E9C2E7
				myPollingAMF.piggybackingEnabled = true; //makes quick response for a polling channel, only on sending machine though...
				var channelSet:ChannelSet = new ChannelSet();
				channelSet.addEventListener(ChannelEvent.CONNECT, channelConnected);
				channelSet.addChannel(myStreamingAMF); //looks like need to add streaming first, then polling, else doesn't work
				//channelSet.addChannel(myPollingAMF); //if you add polling, it only ever polls, doesn't stream
				consumer.channelSet = channelSet;
				producer.channelSet = channelSet;
				var name:String= "chat"; //this needs to be 'chat', listed as a destination in BlazeDS 'messaging-config.xml'
				consumer.destination = name;
				producer.destination = name;
				consumer.addEventListener(MessageEvent.MESSAGE, messageHandler);
				consumer.subscribe();
				Debug.log("client id: " + mx.messaging.FlexClient.getInstance().id);
            }

			private function send():void
			{
				Debug.log("send");
				var message:IMessage = new AsyncMessage();
				message.body.chatMessage = msg.text;
				producer.send(message);
				msg.text = "";
			}

			private function messageHandler(e:MessageEvent):void
			{
				Debug.log("receive");
				log.text += e.message.body.chatMessage + "\n";
			}
			private function channelConnected(e:ChannelEvent):void {
				Debug.log(e);
			}
			private function logFault(e:FaultEvent):void{
				Debug.log(e);
			}
        ]]>
    </mx:Script>

    <mx:DataGrid dataProvider="{ro1.getProducts.lastResult}" width="734.1666" height="326.9697"/>
    <mx:Button label="Get Data" click="ro1.getProducts()"/>
	<mx:Panel title="Chat" width="735.4546" height="249.01517">
		<mx:TextArea id="log" width="699.01514" height="162.42424"/>
		<mx:ControlBar>
			 <mx:TextInput id="msg" width="100%" enter="send()"/>
			 <mx:Button label="Send" click="send()"/>
		</mx:ControlBar>
	</mx:Panel>
</mx:WindowedApplication>