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Signal in Service is null

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JeffW.

06 Aug, 2011 05:14 PM

hi,
I'm trying to dispatch a signal from a service that receives external OSC messages using a Tuio as3 lib, but the signal doesn't exist.
I'm using the latest RL and Signals extension.

In my ApplicationContext I added:
injector.mapSingleton(Receiver); signalCommandMap.mapSignalClass(ParseReceivedDataSignal,ParseReceivedDataCommand);

The signal class, which extends Signal:
public class ParseReceivedDataSignal extends Signal { public function ParseReceivedDataSignal() { super(OSCMessage); } }

In the Receiver class, which extends Actor and implements IOSCListener (from the Tuio lib), I inject the signal:
[Inject] public var parseReceivedDataSignal:ParseReceivedDataSignal;

and dispatch:
parseReceivedDataSignal.dispatch(oscmsg);

but the signal traces null.

I also wonder how the Receiver class would know about the Signal? But I based this on the RL Signals Cafe example here
http://joelhooks.com/2010/02/14/robotlegs-as3-signals-and-the-signa...
which seems to do the same.

thanks!
Jeff.

1. 1 Posted by pavel.fljot on 06 Aug, 2011 05:44 PM

   

   When do you try to access parseReceivedDataSignal? It will be available only after injection occurs, try to create [PostConstruct] public function onInjected():void{ should be available here }

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2. 2 Posted by neil on 06 Aug, 2011 05:45 PM

   

   I presume that you have mapped the Signal into the injector:
   injector.mapSingleton(ParseReceivedDataSignal);

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3. 3 Posted by JeffW. on 06 Aug, 2011 06:30 PM

   

   thanks for te quick reply:).

   I'd tried [PostConstruct] but no luck

   and I tried - but am not using now (cos i read it could cause problems)
   injector.mapSingleton(ParseReceivedDataSignal);

   Injecting and dispatching the same signal from a mediator class doesn't cause the same problems...

   I instantiate the service the same moment that I add the view of wich the mediator does diaptch the signal.

   Is it necessary to use an interface for a service?

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4. 4 Posted by JeffW. on 06 Aug, 2011 07:44 PM

   

   well, this is driving me crazy,
   so I stripped it down to its simplest form,
   see the attachment.

   I 'd be grateful if you can take a look to see what I'm missing here!

   • RobotLegsSignalsTestFlash.zip 151 KB
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5. 5 Posted by neil on 06 Aug, 2011 07:45 PM

   

   OK, but how are you mapping the Signal into the injector? your code does not show this

   You have to make sure that you map the same instance into the injector as you are mapping to the signalCommandMap

   var prdSignal:ISignal = new ParseReceivedDataSignal();

   injector mapValue(ParseReceivedDataSignal, prdSignal);

   injector.mapSingleton(Receiver);

   signalCommandMap.mapSignalClass(prdSignal,ParseReceivedDataCommand);

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6. 6 Posted by pavel.fljot on 06 Aug, 2011 07:51 PM

   

   Jeff,

   oh the thing is that no injection happens into your TestService. Instead of using "var testService:TestService = new TestService();" in this particular example you should at least write

   var testService:TestService = injector.getInstance(TestService) as TestService;
   

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7. 7 Posted by JeffW. on 06 Aug, 2011 07:59 PM

   

   ah great, it now works :)

   Thanks a lot, Pavel, I hadn't seen that way of injecting yet .

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8. 8 Posted by neil on 06 Aug, 2011 08:26 PM

   

   you can't just create the TestService as normal:

   var testService:TestService = new TestService();

           testService.startDispatching();
   

   you have to create it via the injector, either by using [Inject] or:

   var testService:TestService = injector.getInstance(TestService);

   and you will need to inject the Signal as per my previous post

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9. 9 Posted by neil on 06 Aug, 2011 08:27 PM

   

   oh, late to the party again I see :-/

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10. 10 Posted by JeffW. on 06 Aug, 2011 08:30 PM

    

    thanks anyway Neil :)

    It wasn't necessary for me to inject the signal the way you wrote, which btw gives an error because you can't pass an instance to the mapSignalClass method, which requires a Class name.

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11. 11 Posted by neil on 06 Aug, 2011 09:40 PM

    

    ah, there's another method mapoSignal...
    but as long as it works

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12. 12 Posted by JeffW. on 07 Aug, 2011 11:13 AM

    

    yes, it works, but the next step makes me wonder which way to go.

    So I'm receiving data now in the Receiver class, and I dispatch them with a Signal to a Command, which handles the data and sets resulting values in the Model. Now I want to dispatch these data from the Model, so that a Sender class can send osc packets, to which another app is listening.

    What sort of class should Sender be?
    I guess not a Service, because services normally only receive data and don't listen for evens/signals?
    I guess not a Mediator, because a mediator is normally hooked up to a view and the sender doens't need a view?
    Should I just use a command in which the data are sent?

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13. 13 Posted by pavel.fljot on 07 Aug, 2011 11:18 AM

    

    Jeff,

    I think Sender is basically a Service, and can be triggered by Command (so Command is mapped to Signal, which dispatches from Model on update).

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14. 14 Posted by JeffW. on 07 Aug, 2011 11:50 AM

    

    But then I'd need to listen for the Signal in the Service, right? Isn't that highly discouraged?
    Or do you mean that I should inject the Sender into the Command and call a method in Sender from the Command?

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15. 15 Posted by pavel.fljot on 07 Aug, 2011 11:56 AM

    

    Sender into Command

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16. 16 Posted by JeffW. on 07 Aug, 2011 03:23 PM

    

    got it, and it works, I guess this thread can be closed..

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17. 17 Posted by pavel.fljot on 07 Aug, 2011 07:27 PM

    

    Jeff,

    so you're doing some touch-screen development (TUIO)? Maybe you could join development https://github.com/fljot/Gestouch
    The TUIO protocol integration is on TODO list, but I haven't worked with that at all, don't have any hardware for that =(

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18. 18 Posted by JeffW. on 07 Aug, 2011 07:36 PM

    

    no, I'm using the as3 tuio library because it makes it easy to work with sending and receiving osc messages between Air and other apps...but thanks for suggesting the development participation.

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19. Ondina D.F. closed this discussion on 01 Nov, 2011 04:27 PM.