Hi Gareth,

Here's some answers assuming you subscribe to the gist of the MVC presentation I gave at WebDU last year

http://onair.adobe.com/blogs/videos/2007/05/01/webdu-easy-as-mvc-architecture-and-frameworks-for-non-believers-robin-hilliard/

On 01/04/2008, at 8:51 AM, Gareth Edwards wrote:

I have created a some what complicated services.as 

(EnterpriseServiceLocator) and I'm trying to give some limited control 

back to the end user, and allow them to select from a list of available 

AMFChannels. I almost have it all working, but have a couple of 

questions before I continue to finish the work in this area.

- Is it o.k for my Service Locator to access the Model locator?

Strictly speaking no, because the ServiceLocator is part of the business layer, and this would introduce a dependency on a particular model from your business layer (you could imagine the business layer being useful to many distinct Flex apps with different models).  That said the model changes the least out of the MVC players so in some situations where the model and service were very closely interdependent you could argue that this wasn't too great a loss.

- Is it o.k for my Service Locator to modify the values in the Model?

See above.

- How would you best manage your application to "WAIT" until various 
checks on the AMFChannels are done before doing anything further ?

I'd queue the requests, going with the philosophy that like DAOs on the server you are trying to hide the complexity of how the services work from the rest of the application.  As far as the command knows, it makes the asynchronous call and it just takes a while to come back while some tests are done.  In fact something like this happens anyway when Flash tests for the appropriate  cross domain file on the server before making an RPC call.

- Would it be better to create an Event / Command to do the required 
logic to determine the AMFChannels and then use this to set the Model, 
then have the service locator access the Model for read only?

I would be inclined to keep the details of the selected channel in the Service Locator or a service in the Service Locator and not in the model. 

- When the user selects an available AMFChannel, the system needs to 
move the selected Channel to the TOP of the ChannelSet
- I'm doing this by creating an array of AMFChannels, storing these 
in the Model, then reading them into the service locator and ChannelSet 
when required.
- How do I ensure no further actions take place until this update is 
done.

I'd add methods to the service to get lists of channel set names and select the channel - the rest of the app doesn't need to know that they're channel sets, just choices like "unsecure", "secure" or whatever you have.

You could queue the calls - the neatest way (maybe gold-plating, but cute and useful) to do this would be to create a Proxy subclass that decorated your service and queued up function calls that it would play back when you set an enabled property to true.  This is like the access control proxy pattern.  There might be something in the SDK that does this already.

HTH,

Robin

	ROBIN HILLIARD Chief Executive Officer robin@rocketboots.com.au RocketBoots Pty Ltd Level 11 189 Kent Street Sydney NSW 2001 Phone +61 2 9323 2507 Facsimile +61 2 9323 2501 Mobile +61 418 414 341 www.rocketboots.com.au

 

I have created a some what complicated services.as
(EnterpriseServiceLocator) and I'm trying to give some limited control
back to the end user, and allow them to select from a list of available
AMFChannels. I almost have it all working, but have a couple of
questions before I continue to finish the work in this area.

- Is it o.k for my Service Locator to access the Model locator?
- Is it o.k for my Service Locator to modify the values in the Model?
- How would you best manage your application to "WAIT" until various
checks on the AMFChannels are done before doing anything further ?
- Would it be better to create an Event / Command to do the required
logic to determine the AMFChannels and then use this to set the Model,
then have the service locator access the Model for read only?
- When the user selects an available AMFChannel, the system needs to
move the selected Channel to the TOP of the ChannelSet
     - I'm doing this by creating an array of AMFChannels, storing these
in the Model, then reading them into the service locator and ChannelSet
when required.
     - How do I ensure no further actions take place until this update is
done.

I know that I can achieve what I need one way or another, but would like
more opinions on the best way to do this.

Cheers
Gareth.

Hi All,

Can any one guide me on how to fetch values from the "additionalCompilerArguments" property from the "compiler" tag in ".actionScriptProperties" on the fly, i.e.) via programming or by using any inbuilt action script to fetch the value programmatically..

Actually my requirement is to populate the compiler argument's -locale value dynamically on the fly without placing these locale values during  compile time.

 
Cheers,
Madhu K

Madhu K
 
Email : Madhu.Kma@... 
 
 
Please do not print this email unless it is absolutely necessary. Spread environmental awareness.

Hi,

Senario:
1) view-1 dispatches an event.
2) model properyt-1 gets modified within the command's execute method
3) now due to the data binding, all the views will be updated which
have used data binding with model property-1.

I want to control that view-1 don't receive the binding call because
this view itself dispatched the event.

Regards,
Ahmed

Hi There,

Could any one please help me with some good study materials or tutorial links describing about
all the configuration files like services-config.xml, remoting-config.xml, proxy-config.xml, messaging-config.xml,
data-management-config.xml, etc in a Flex project (implementing Cairngorm framework) when deploying it as a web application.

Thanks in advance for your time and help.
 
Cheers,
Madhu K
Please do not print this email unless it is absolutely necessary. Spread environmental awareness.

 
 

In general in Cairngorm you maintain state in the model and have the
view listen to changes to the state and react accordingly.  So add a
variable to your model locator loggedIn:Boolean.  Then have your login
 screen listen to changes in the variable either via a ChangeWatcher
or Binding, and clear the controls when it goes false.

--- In cairngorm-devel@yahoogroups.com <mailto:cairngorm-devel%40yahoogroups.com> , "malik_robinson"
<Malik_Robinson@...> wrote:
>
> Hi,
>
> I have a class called LogoutCommand.as, code snippet below:
>
> public class LogoutCommand implements ICommand {
>
>          public var modelLocator:ViewModelLocator =
> ViewModelLocator.getInstance();
>
>          public function LogoutCommand() {
>
>          }
>
>          public function execute(event:CairngormEvent):void {
>
>              modelLocator.workflowState = ViewModelLocator.LOGIN_SCREEN;
>              modelLocator.loginBoxMessage = "You have been logged out!";
>
>          }
>
>
>
>      }
>
> The above code works fine, but when the screen changes back to the login
> screen, the username and password fields are still filled in with the
> users' original entries.
>
>   On logout, I would like those fields to be cleared.  I am unsure
on how
> I would access the fields from my Command Class.  The syntax should be
> simple, I think I am struggling with "accessibility" and knowing how to
> interact with an object in a different file or whatever...
>
> On my "LoginScreen.mxml" file I have this control:      <mx:TextInput
> id="username" width="180"/>   I should be able to set its text or value
> property to empty string or something, just not sure how to do that from
> the Command Class if that makes sense.
>
> Any help appreciated...
>
> -
>

 
    

In general in Cairngorm you maintain state in the model and have the
view listen to changes to the state and react accordingly.  So add a
variable to your model locator loggedIn:Boolean.  Then have your login
  screen listen to changes in the variable either via a ChangeWatcher
or Binding, and clear the controls when it goes false.

--- In cairngorm-devel@yahoogroups.com, "malik_robinson"
<Malik_Robinson@...> wrote:
>
> Hi,
>
> I have a class called LogoutCommand.as, code snippet below:
>
> public class LogoutCommand implements ICommand {
>
>          public var modelLocator:ViewModelLocator =
> ViewModelLocator.getInstance();
>
>          public function LogoutCommand() {
>
>          }
>
>          public function execute(event:CairngormEvent):void {
>
>              modelLocator.workflowState = ViewModelLocator.LOGIN_SCREEN;
>              modelLocator.loginBoxMessage = "You have been logged out!";
>
>          }
>
>
>
>      }
>
> The above code works fine, but when the screen changes back to the login
> screen, the username and password fields are still filled in with the
> users' original entries.
>
>   On logout, I would like those fields to be cleared.  I am unsure
on how
> I would access the fields from my Command Class.  The syntax should be
> simple, I think I am struggling with "accessibility" and knowing how to
> interact with an object in a different file or whatever...
>
> On my "LoginScreen.mxml" file I have this control:      <mx:TextInput
> id="username" width="180"/>   I should be able to set its text or value
> property to empty string or something, just not sure how to do that from
> the Command Class if that makes sense.
>
> Any help appreciated...
>
> -
>

Try this little AIR app I whipped up. Should make your life a bit
easier when creating a pile of VO's.

http://www.dgrigg.com/post.cfm/10/17/2007/Value-object-creator

Derrick
--------------
Derrick Grigg
www.dgrigg.com

I've been doing database/Flash/Flex integration for a long time and
have never seen anything that can create actionscript VO stub code  of
database records. I created a tool a few years ago at an old job where
you could essentially do that, give it a comma separated list of
columns and it would create the stub code. Maybe it's time to rebuild
the app in AIR.

Derrick
--------------
Derrick Grigg
www.dgrigg.com

 
 

Back in July Eric Feminella blogged about:

AIR Cairngorm (AIR extensions for Cairngorm)
http://www.ericfeminella.com/blog/category/apollo/page/4/

How can we get updates into the core Cairngorm code base?  I am asking most immediately regarding updates along the lines of the extensions that Eric has developed and made available at the link above for working with the new Adobe AIR services.

             Thanks,

              g
 
    

hi folks.

Just wondering, does anyone know of an eclipse (or anything else in
fact) tool for automatically creating VOs from MySQL tables?

It's just such a pain of a jop having to copy it all by hand, and also
another place where errors can creep in.

In fact it wouldn't even need to creat propper actionScript code, just
something like it that I could then change into the propper format.

The project I'm currentl;y working on is a recoding of a system that
was originally written in access and SQL. so the Database is already
there (since converted in MySQL) and there are loads of tables and
making all the VOs is becomming a real pain.

any ideas anyone?

cheers
glenn.

Hi,

Wonder if anyone might be able to help me...

I've recently started using LCDS2.5 and managed to get a demo app
working, connecting to our app database etc.

I then tried to port our existing app into LCDS, which is a Cairngorm
app, and tried to translate one of the existing web services to a
remoteObject instead - coincidentally (well not really!) the
remoteObject I managed to get working in my 'demo'.

The problem is, however, that the remoteObject never seems to get invoked.

The Services.mxml contains:

<mx:RemoteObject
         id="dbService"
         destination="database"
         showBusyCursor="true">

    <mx:method name="executeSQL"/>
</mx:RemoteObject>

And the delegate looks like this:

package com.db.storage.business
{
  import mx.rpc.IResponder;
  import com.adobe.cairngorm.business.ServiceLocator;
  import mx.rpc.events.FaultEvent;
  import mx.rpc.events.ResultEvent;
  import mx.rpc.AbstractOperation;
  import mx.rpc.AsyncToken;

  public class DSDelegate
  {
   private var responder:IResponder;
   private var service:Object;

   public function DSDelegate(responder:IResponder)
   {
    this.service = ServiceLocator.getInstance().getRemoteObject(
"dbService" );
    this.responder = responder;
   }

   public function executeSQL(query:String):void {
    var call:AsyncToken = service.executeSQL( query.toUpperCase() );
    call.addResponder( responder );
   }
  }
}


In debug, the DSDelegate function is invoked and the executeSQL is
also invoked but nothing ever seems to get fired (or, of course,
returned). I don't think the remoteObject is being fired at all since
there's no console message indicating that it is (I have the log set
to show all activity).

The remoting-config.xml is identical to the non-cairngorm demo that
works as is all of the java side code - the only thing that's changed
is that I've tried to introduce Cairngorm to the equation.

I know this is hard to comment on without being closer to the codeline
but I was just hoping someone here would have a suggestion - we
basically have until friday to get this working properly or else we're
going to most likely abandon using LiveCycle Data Services entirely -
our experience so far with the product has been pretty miserable -
this is pretty much the final straw. I'd like to push on with it
because it *should* offer us some nice new functionality, particularly
the ability to produce PDF files displaying flex charts in them - but
there's a limit to how long you can try to keep the flame burning!

So anyway, all help, comments, suggestions etc gratefully received!

Thanks,

Jamie.

No, this syntax error was made in cut&paste process.

Well, the problem is - as soon as I reference my first web service
from the delegate (and SURE, this web service is already wsdl-loaded!)
the other services are trying to connect to their WSDL-s (which are
empty strings at that time).
If I reference this service from some ASMX, the whole thing doesn't
happen.

No, this syntax error was made in cut&paste process.

Well, the problem is - as soon as I reference my first web service
from the delegate (and SURE, this web service is already wsdl-loaded!)
the other services are trying to connect to their WSDL-s (which are
empty strings at that time).
If I reference this service from some ASMX, the whole thing doesn't
happen.

Hi Danko,

Are you sure its trying to load up the other WSDLs?

service = ServiceLocator.getInstance
> ().getWebService"publicWebService") as WebService; // this is the
> line which brings up error

has an error, as its missing a ( I have updated it below

service = ServiceLocator.getInstance
> ().getWebService("publicWebService") as WebService; // this is the
> line which brings up error

Not sure if this is a cut and paste error on your behalf... or your
problem...

Regards

Mark

--- In cairngorm-devel@yahoogroups.com, "Danko Kozar"
<danko_kozar@...> wrote:
>
> I've got a problem with ServiceLocator, and that problem didn't
> exist until my today's Flex & Cairngorm upgrade (to Hotfix 2 +
> Cairngorm 2.2).
>
> Context:
> --------
> In my <mx:ServiceLocator> I've got 3 web services defined, one of
> which is a public one (the others are protected). "Public" means
> it's not secured on the server and contains only "login(user, pass)"
> method (and it has a known URL in the application start). After the
> successfull login, the login method returns WSDL URLs of all other
> web services.
>
> Problem:
> --------
> The problem is that a service locator IMMEDIATE LOADS ALL WSDL-s of
> it's (web service) children. But: this happens only when the
> ServiceLocator is referenced FROM THE DELEGATE CLASS (using 'service
> = ServiceLocator.getInstance().getWebService("publicWebService") as
> WebService;'). When it is referenced from the main page, this
> problem doesn't exist. Of course, these other web services doesn't
> have proper WSDL-s assigned yet, so I got an error.
>
> Note: I HAVE TO reference the web service from the delegates since I
> have to invoke web service methods from that delegates.
>
> Since I didn't quite understand what's going on here, please give me
> some advice. Thanks!
>
> Code:
> -----
>
> public class LoginDelegate
>     {
>     private var responder: IResponder;
>     private var service: WebService;
>
>     public function LoginDelegate(responder: IResponder)
>     {
>         service = ServiceLocator.getInstance
> ().getWebService"publicWebService") as WebService; // this is the
> line which brings up error
>         this.responder = responder;
>     }
>
>     public function login(user:String, pass:String):void
>     {
>  var token:AsyncToken = service.Login(user, pass);
>  token.resultHandler = this.onResult;
>  token.faultHandler = this.onFault;
>     }
>
>     //-----------------------
>     protected function onResult(event:ResultEvent):void
>     {
>         responder.result(event);
>     }
>     protected function onFault(event:FaultEvent):void
>     {
>         responder.fault(event);
>     }
> }
>
> Error Detail:
> -------------
> TypeError: Error #1009: Cannot access a property or method of a null
> object reference.
>  at business::Services/__mainWebService_fault()
>  at
> flash.events::EventDispatcher/flash.events:EventDispatcher::dispatchE
> ventFunction()
>  at flash.events::EventDispatcher/dispatchEvent()
>  at mx.rpc::AbstractService/dispatchEvent()
>  at mx.rpc.soap.mxml::WebService/dispatchEvent()
>  at mx.rpc.soap::WebService/loadWSDL()
>  at com.adobe.cairngorm.business::WebServices/register()
>  at
> com.adobe.cairngorm.business::ServiceLocator/get ::webServices()
>  at com.adobe.cairngorm.business::ServiceLocator/getWebService
> ()
>  at business::LoginDelegate$iinit()
>  at command::LoginCommand/execute()
>  at
> com.adobe.cairngorm.control::FrontController/com.adobe.cairngorm.cont
> rol:FrontController::executeCommand()
>  at
> flash.events::EventDispatcher/flash.events:EventDispatcher::dispatchE
> ventFunction()
>  at flash.events::EventDispatcher/dispatchEvent()
>  at
> com.adobe.cairngorm.control::CairngormEventDispatcher/dispatchEvent()
>  at component.form::LoginForm/::login()
>  at component.form::LoginForm/::validateMe()
>  at component.form::LoginForm/__loginButton_click()
>

I've got a problem with ServiceLocator, and that problem didn't
exist until my today's Flex & Cairngorm upgrade (to Hotfix 2 +
Cairngorm 2.2).

Context:
--------
In my <mx:ServiceLocator> I've got 3 web services defined, one of
which is a public one (the others are protected). "Public" means
it's not secured on the server and contains only "login(user, pass)"
method (and it has a known URL in the application start). After the
successfull login, the login method returns WSDL URLs of all other
web services.

Problem:
--------
The problem is that a service locator IMMEDIATE LOADS ALL WSDL-s of
it's (web service) children. But: this happens only when the
ServiceLocator is referenced FROM THE DELEGATE CLASS (using 'service
= ServiceLocator.getInstance().getWebService("publicWebService") as
WebService;'). When it is referenced from the main page, this
problem doesn't exist. Of course, these other web services doesn't
have proper WSDL-s assigned yet, so I got an error.

Note: I HAVE TO reference the web service from the delegates since I
have to invoke web service methods from that delegates.

Since I didn't quite understand what's going on here, please give me
some advice. Thanks!

Code:
-----

public class LoginDelegate
     {
     private var responder: IResponder;
     private var service: WebService;

     public function LoginDelegate(responder: IResponder)
     {
         service = ServiceLocator.getInstance
().getWebService"publicWebService") as WebService; // this is the
line which brings up error
         this.responder = responder;
     }

     public function login(user:String, pass:String):void
     {
	 var token:AsyncToken = service.Login(user, pass);
	 token.resultHandler = this.onResult;
	 token.faultHandler = this.onFault;
     }

     //-----------------------
     protected function onResult(event:ResultEvent):void
     {
         responder.result(event);
     }
     protected function onFault(event:FaultEvent):void
     {
         responder.fault(event);
     }
}

Error Detail:
-------------
TypeError: Error #1009: Cannot access a property or method of a null
object reference.
	 at business::Services/__mainWebService_fault()
	 at
flash.events::EventDispatcher/flash.events:EventDispatcher::dispatchE
ventFunction()
	 at flash.events::EventDispatcher/dispatchEvent()
	 at mx.rpc::AbstractService/dispatchEvent()
	 at mx.rpc.soap.mxml::WebService/dispatchEvent()
	 at mx.rpc.soap::WebService/loadWSDL()
	 at com.adobe.cairngorm.business::WebServices/register()
	 at
com.adobe.cairngorm.business::ServiceLocator/get ::webServices()
	 at com.adobe.cairngorm.business::ServiceLocator/getWebService
()
	 at business::LoginDelegate$iinit()
	 at command::LoginCommand/execute()
	 at
com.adobe.cairngorm.control::FrontController/com.adobe.cairngorm.cont
rol:FrontController::executeCommand()
	 at
flash.events::EventDispatcher/flash.events:EventDispatcher::dispatchE
ventFunction()
	 at flash.events::EventDispatcher/dispatchEvent()
	 at
com.adobe.cairngorm.control::CairngormEventDispatcher/dispatchEvent()
	 at component.form::LoginForm/::login()
	 at component.form::LoginForm/::validateMe()
	 at component.form::LoginForm/__loginButton_click()

A Command represents a user action and a Delegate represents a service call 

I agree the chainable events are quite useful, however its not that
useful if you have 2 buttons, like a save and refresh, which both
trigger Cairngorm Events... If the user in their wisdom presses one
directly after the other the call on the delegate causes issue...