Hi Jason, I hope you don't mind me addressing you of list. If you do, please ignore this message and I apologize to you!
I am trying to grasp the MVC pattern, but it is very hard for me. I am looking for a very simple example which explains the way it works. If you can help me with this, I would be very greatful. Thanks in advance. Kind regards Cor van Dooren The Netherlands -----Original Message----- From: flashcoders-boun...@chattyfig.figleaf.com [mailto:flashcoders-boun...@chattyfig.figleaf.com] On Behalf Of Merrill, Jason Sent: dinsdag 19 januari 2010 17:35 To: Flash Coders List Subject: RE: [Flashcoders] Using MVC for a site framework This is my opinion, I'm sure others will have their own that may differ (and probably recommend you check out some frameworks - though that can be a lot to tackle) : the controller would listen to the model to know when the data is ready and available. It would then tell the view to start building. The main class would hold the references to the model, view, controller, but would not command any classes to do anything really. You could have the view listen to the model as well and skip the controller doing it, but I like the view to be more decoupled than that. I usually try and keep most listeners in the controller where possible, though many end up in the view, depending on the situation. I never have listeners in the model though, only events that are dispatched. I actually have the model start and do it's own XML loading, but you could have the controller tell it to do that, just seems like an unnecessary step. Another thing I do is have a main class called MVC that extends Sprite or DisplayObject which initializes the model, view, controller, in order, dispatches an event when all three are initialized, and provides access to each via a singleton implementation. It allows me to access any part of a model, view, controller from any other part just by calling MVC.instance. Then it's just var _mvc:MVC = MVC.instancel; then _mvc.model.myprop or _mvc.view.update() or whatever. That class looks like this: package mvc { import events.MVCEvent; import events.view.ViewEvent; import events.controller.ControllerEvent; import events.model.ModelEvent; import mvc.controller.Controller; import mvc.model.Model; import mvc.view.View; import flash.display.Sprite; /** * ... * @author Jason Merrill - Bank of America */ public class MVC extends Sprite { public var view:View; public var model:Model; public var controller:Controller; private static var _instance:MVC; public function MVC() { if ( _instance != null ) { throw new Error( "Only one MVC instance should be instantiated. Use MVC.instance instead." ); } else { _instance = this; } } public function initialize():void { model = new Model(); view = new View(); controller = new Controller(); model.addEventListener(ModelEvent.INITIALIZED, onModelInitialized); controller.addEventListener(ControllerEvent.INITIALIZED, onControllerInitialized); view.addEventListener(ViewEvent.INITIALIZED, onViewInitialized); model.initialize(); } private function onModelInitialized(event:ModelEvent):void { model.removeEventListener(ModelEvent.INITIALIZED, onModelInitialized); view.initialize(); } private function onViewInitialized(event:ViewEvent):void { addChild(view); view.removeEventListener(ViewEvent.INITIALIZED, onViewInitialized); controller.initialize(); } private function onControllerInitialized(event:ControllerEvent):void { controller.removeEventListener(ControllerEvent.INITIALIZED, onControllerInitialized); dispatchEvent(new MVCEvent(MVCEvent.INITIALIZED)); } public static function get instance():MVC { if ( _instance == null ) { throw new Error( "MVC singleton instance not created yet." ); } return _instance; } } } Jason Merrill Bank of America Global Learning Learning & Performance Soluions Join the Bank of America Flash Platform Community and visit our Instructional Technology Design Blog (note: these are for Bank of America employees only) -----Original Message----- From: flashcoders-boun...@chattyfig.figleaf.com [mailto:flashcoders-boun...@chattyfig.figleaf.com] On Behalf Of allandt bik-elliott (thefieldcomic.com) Sent: Tuesday, January 19, 2010 11:09 AM To: Flash Coders List Subject: [Flashcoders] Using MVC for a site framework Hi guys I'm currently feeling my way through the o'reilly design patterns book and am going through the mvc design pattern as a way of dealing with (micro)site structures - dealing with opening and closing pages, loading data etc but i have a couple of questions that you guys will probably be able to answer... i have a config xml file that points to the data xml, site css and fonts.swf. I take it that the controller should have the responsibility of loading those files and storing the results in the model. However if i include the site structure in the data xml as i would usually do, which part of the triad should be instantiating the views to create the pages? The book is set up that the Main.as class would be instantiating the views and creating the site structure but that doesn't fit if the controller is loading the xml files into the model. I would guess that the controller would trawl the xml and instantiate the page views and add them to the model but i'm not 100% on this I'd really appreciate your time on this matter as I'd like to build a set of classes that work with more than one project thanks a _______________________________________________ Flashcoders mailing list Flashcoders@chattyfig.figleaf.com http://chattyfig.figleaf.com/mailman/listinfo/flashcoders _______________________________________________ Flashcoders mailing list Flashcoders@chattyfig.figleaf.com http://chattyfig.figleaf.com/mailman/listinfo/flashcoders No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.730 / Virus Database: 270.14.149/2631 - Release Date: 01/18/10 17:56:00 _______________________________________________ Flashcoders mailing list Flashcoders@chattyfig.figleaf.com http://chattyfig.figleaf.com/mailman/listinfo/flashcoders
