Apache – The best Flex Framework you have used so far

I did a simple bootstrap similar to Borek (see below). I would love to get rid of the mxml file, but if I don't have it, I don't get any of the standard themes that come with Flex (haloclassic.swc, etc). Does anybody know how to do what Theo suggests and still have the standard themes applied?

Here's my simplified bootstrapping method:

main.mxml

<?xml version="1.0" encoding="utf-8"?>
<custom:ApplicationClass xmlns:custom="components.*"/>

ApplicationClass.as

package components {
    import mx.core.Application;
    import mx.events.FlexEvent;
    import flash.events.MouseEvent;
    import mx.controls.Alert;
    import mx.controls.Button;

    public class ApplicationClass extends Application {
        public function ApplicationClass () {
            addEventListener (FlexEvent.CREATION_COMPLETE, handleComplete);
        }
        private function handleComplete( event : FlexEvent ) : void {
            var button : Button = new Button();
            button.label = "My favorite button";
            button.styleName="halo"
            button.addEventListener(MouseEvent.CLICK, handleClick);
            addChild( button );
        }
        private function handleClick(e:MouseEvent):void {
            Alert.show("You clicked on the button!", "Clickity");
        }
    }
}

Here are the necessary updates to use it with Flex 4:

main.mxml

<?xml version="1.0" encoding="utf-8"?>
<local:MyApplication xmlns:fx="http://ns.adobe.com/mxml/2009" xmlns:local="components.*" />

MyApplication.as

package components {
    import flash.events.MouseEvent;
    import mx.controls.Alert;
    import mx.events.FlexEvent;
    import spark.components.Application;
    import spark.components.Button;

    public class MyApplication extends Application {
        public function MyApplication() {
              addEventListener(FlexEvent.CREATION_COMPLETE, creationHandler);
        }
        private function creationHandler(e:FlexEvent):void {
            var button : Button = new Button();
            button.label = "My favorite button";
            button.styleName="halo"
            button.addEventListener(MouseEvent.CLICK, handleClick);
            addElement( button );
        }
        private function handleClick(e:MouseEvent):void {
            Alert.show("You clicked it!", "Clickity!");
        }
    }
}

• How productive it is to program in Flex compared to the .Net + Silverlight?

Way more productive than Silverlight as it has a much richer and capable control library. Silverlight is rapidly gaining ground here though. I think by the time SL 4 comes out they will reach feature parity, maybe even SL 3.

• Any technical advantages over other frameworks?

If you can create it in Photoshop, you can pretty much do it in Flex with the help of the Flash drawing API. If you want to build very interesting data visualizations (tree/node diagrams, such as an org chart) you can do this Flex without a ton of work.

• Any disadvantages ?

There is no server-side component to ActionScript so you need to find a way to pass data between Flex and your backend, be it Java, .NET, PHP, etc. There are libraries out there to AMF remoting with just about any backend which makes it easy. But as far as the objects you pass between the two, you need to maintain both or use a code generation tool to create AS3 classes from your backend classes.

• Does it have any known scaling issues?

Flex is simply a presentation technology so this question doesn't really apply.

• What kind of web servers can it be hosted on?

Again, only a presentation technology. It compiles out to a SWF file that is loaded by the browser over HTTP and then executes inside of the Flash Player plugin.