Joel Hooks

the ViewStack is one of the most convenient containers for this type of interaction using a "page" paradigm.

Rogerio Kioshi wrote:Hi,

I'd like to know if it is possible to program games using Flex.

Thank you

Flex is used a lot for the surrounding GUI of games. Flex is generally not used for the "game loop" portion of games that requires higher performance. This is less true for say a card game then it is for a firts person shooter, of course. Checkout the Push Button Engine. Great platform for building games for the Flash Platform.

Shashank Agarwalg wrote:Flex and ColdFusion
Flex and java
Flex and .net

If i choose Flex with java which advantages i get.

Which mid-tier technology are the developers you work with more skilled at? Which makes more sense from a deployment standpoint for your project?

Java gives you all of the technology investments Adobe has put into that platform (Blaze DS/LCDS, Spring Integration, etc). That might be enough to say Java has the edge here. I've worked with dotnet, Java, Python, Ruby, and PHP mid-tiers with great success. Asking which is best is really hard to answer. It depends...

Anup Francis wrote:Authors,
What is your opinion on using AS3 signals?
Do you think its a better idea to go with signals for creating new apps?
I haven't come across the use of signals in any of the places I have worked.
Only came to know recently about it.
I read up on it and it seems to be good. But seriously, do you guys see it being a used a lot with respect to
event based communication?

I think Signals is an excellent solution to an obvious disfunction of events:

You can't express events via an interface

Signals allow you to observe messages emitted from a concrete instance through its interface. This is very powerful.

So when is it appropriate to use Signals? For me, I like to keep Signals on the application layer and don't use them as much in my visual components. When I am developing visual components I prefer them to follow standard Flash/Flex approaches. I use Signals in the Application tier in conjunction with Robotlegs (which has a lot of Signals support via plugin libraries and utilities).

This is my preference, but I know people that use Signals everywhere, including view components.

At the end of the day they are both Observer pattern implementations. Events are "normal" for Flash Platform development, and there is a lot to be said for that. Signals can allow for more expressive OOP, and there is a lot to be said for that as well. I use a mix with much success. Your mileage may vary ;)

Anup Francis wrote:From your personal experiences, which framework do you guys prefer to use most while creating Flex based applications?
RobotLegs, Mate, Swiz or Parsley.
I have worked with Mate previously and have found it be quite good.
I have also read through the documentation on RobotLegs and Parsley.
I like them both but I believe Parsley could be a more well rounded library with more features especially the Spicelib As3 library.
RobotLegs is a pretty small framework but easy to use and also has AS3 signals support.
I have never had a chance so far, to try out these 2 frameworks in a real world app.
So, would like to know what are your preferences regarding frameworks?

I use and contribute to Robotlegs (and chapter 19 of Flex 4 in Action has a large section on it). I also use Parsley and really like it.

Parsley is everything and the kitchen sink. It is heavy in a lot of ways and more complex because of the expansive features that it provides. This is good and bad as it adds to the complexity. The framework is ~20k lines of code itself. I really enjoy it and use it with the "Cairngorm 3" prescription for architecture applied with great success.

Robotlegs is a tiny single responsibility framework. It doesn't contain bells and whistles and provides a clear prescription for development. The framework (including SwiftSuspenders) is right around 2k lines of code. Why do I mention the lines of code? Because if you want to truly understand the framework you are using you should understand how it works. Robotlegs is much easier to wrap your brain around in that regard.

I honestly don't know which I would recommend over the other. Both are excellent and built by smart guys (Jens Halm and Shaun Smith). Robotlegs has more community which might mean better support via http://knowledge.robotlegs.org. I also like the way the RL community has taken to building utilities and libraries for RL. In this way, RL gets a lot of the functionality that Parsley has, but as modular building blocs instead of a monolithic framework. it is impossible to say which is appropriate for you. I say learn them both and build cool things with both. You can't go wrong!

Jeremy Anderson wrote:This is a good place to start... http://www.adobe.com/devnet/flex/videotraining.html?sdid=FCMWB

If you're really set on buying a book, I would pick up Flex 4 in Action. Then once you know the Flex basics, you should check out the most excellent book Flex on Java. ;)

I'm going to second this. I also recommend a strong understanding of Actionscript. Learning Flex by itself can lead to a "shallow" understanding of the underlying technology.

I *really* like IntelliJ Idea and 10 has some fantastic Flex/Flash features.

Visual Studio is world class. It is the IDE to beat. Resharper, Isolator, Rhino Mocks, VS itself. There are so many reasons it is an IDE to love. Adobe is working hard to improve Flash Builder, but I honestly don't think it will ever get to VS levels. This is more that it is built on Eclipse and not something I fault Adobe with.

Sonny Gill wrote:Like Joel, I also use IDEA for Flex 3 development. The new 9.0.* versions have very good support for Flex development.
The only thing it lacks is a visual layout designer. For all other tasks, the IDEA support for code completion, refactoring etc. is much better than Flex Builder.
Our team has Flex Builder licenses, but the only time I use it is when I need to do some trial-and-error visual design of a Flex screen.

Honestly I haven't actively used the Design Mode in a long time and don't really miss it. There was some speculation that it might be removed in the next cycle in favor of Flash Catalyst. It would certainly make it easier for Adobe to update the product. I think it is a bit of a nightmare :>

IDEA has quirks, but MAN it compiles fast and I love the FlexUnit integration.

Leonidas Savvides wrote:To learn Flex you start with scripting relative languages mxml, etc , or with learning the menus in Flash Builder? how you proceed after you startup? Learning Flex you must choose a server side scripting language from the ones you know very well, and use it by a way in Flex works? like JAVA if I am familiar with? if yes, your book what server side scripting language make use? If indeed, this is the case, what level of JAVA I must have, SE & EE & ME?

Learning the menus in Flash Builder won't get you very far. It is language driven, and while the IDE provides good support, core language/syntax knowledge is key. The good news is that Actionscript/MXML is relatively easy to learn with prior experience with other languages.

Praful Gupta wrote:Hello ... what are some of the main differences between Flex 3 vs Flex 4? like in terms of messaging mechanisms or data stores etc?

Thanks
Praful

The primary difference is in the component architecture. They have decoupled view components from there "skins" to provide a very nice separation of concerns (presentation vs logic). There hasn't been much (if any) updates in terms of the messaging or data stores.

Bill Johnston wrote:Thank you Paul.

I also realize that Adobe offers a Flexbuilder IDE (Eclipse based), but that Flex can be built without it, of course.

Do the authors of the book recommend - as Adobe does - using the Flexbuilder IDE?

Flash Builder 4 is an excellent IDE. I also regularly use IntelliJ Idea for Flex development with great success. They are still working out Flex 4 support, but it has advantages and would make a Java dev that uses it very happy. That said, Flash Builder is probably the easiest route to get started with Flex development.

jp roberts wrote:Will/can one use flex objects in a web page like one can use a dojo widget. Like just using a flex datagrid embedded on a web page and having the ability to communicate with it via javascript?

One thing about Flex is the size of the framework in the embedded swfs. It is rather large. However, Adobe provides the framework in signed runtime-shared-libraries (RSL) that are cached by the Flash Player. This means that if the visitor has already cached the RSLs then they don't need to retrieve the framework. It makes your SWFs acceptable in terms of size. As Dan says, communicating with the SWF via the ExternalInterface is really easy. The SWF object is a first-class JavaScript citizen. You can do some really cool things this way.

I'm not a big fan of Cairngorm, but have used PureMVC extensively. I'm a contributor to Robotlegs which borrows heavily from PureMVC for its MVCS implementation. The nice part of the non-ServiceLocator DI is that it provides for classes that are less coupled and easier to maintain/test. Generally speaking, I write a lot less code with Robotlegs than I did with PureMVC, which is nice as well.

So Cairngorm<PureMVC<Robotlegs :>

http://wiki.github.com/robotlegs/robotlegs-framework/best-practices

When it gets right down to it I think that process is the most important aspect of development. Give me Cairngorm with Agile Scrum any day over Robotlegs with a Waterfall process. Of course Agile Robotlegs is the best of both worlds.

Julien Castelain wrote:

I was wondering if Flex4 in action covers the usage of the Flex sdk's command line tools such as mxmlc, compc, fdb, asdoc and fcsh, as well as integrating them in java apps

Making use of the Flex SDK Compiler API for Java isn't covered in the book as it would be out of scope for the general audience and deal more with Java then with Flex. For the most part the assumption is that you are using Flash Builder.

Ravi Kiran V wrote:Hi ,


Read that there should be a Single Front Controller per application .

But how to manage this as my application is having number of Modules .

Is it good to have a FrontController per Module??

Please share your ideas.

In a modular application you generally have a shell. The shell facilitates the communication between modules via interfaces. So when considering modules as independent sub-applications, having a FrontController (this is a Cairngorm approach) for each module with a top-level shell FrontController is a good approach.