Comments on: Using [Bindable] & ChangeWatcher in ActionScript-only classes

By: Thomas James

Thomas James — Thu, 10 Jun 2010 17:37:07 +0000

Yet if [Bindable] does not use any Flex framework in an ActionScript project in Flashdevelop or Flashbuilder this fails:

[code]package
{
import flash.display.Sprite;
import flash.events.EventDispatcher;
import flash.events.Event;

public class BindableTest extends Sprite
{
private var _maxFontSize:Number = 15;

public function BindableTest() {
this.maxFontSize = 100;
}

[Bindable(event="maxFontSizeChanged")]
public function get maxFontSize():Number {
trace(" max ");
return _maxFontSize;
}

public function set maxFontSize(value:Number):void {
_maxFontSize = value;
var eventObj:Event = new Event("maxFontSizeChanged");
dispatchEvent(eventObj);
}

}
}
[/code]

Any clues!?

By: Morgan Engel

Morgan Engel — Wed, 09 Dec 2009 00:12:18 +0000

You might consider using a get and set and then just appending the Bindable attribute on the get method. something like:

[Bindable]
public function get property():Object{}
public function set property(o:Object){}

Then you can dispatch listeners in your set and you can listen to them just fine in your AS3 code.

By: James

James — Tue, 14 Jul 2009 23:42:09 +0000

Thanks for the link & clarification Troy.

I guess I misunderstood what the Flex framework actually ‘was’ – and where the framework starts and stops with regards to visual / utilities classes.

By: Troy Gilbert

Troy Gilbert — Tue, 14 Jul 2009 20:30:25 +0000

That’s not actually correct. [Bindable] does not use any Flex Framework specific API (beyond the PropertyChangeEvent class), and the BindingUtils is similar. You do not have to derive from UIComponent or use this only in the context of MXML. I’d recommend watching the binding “deep dive” session from 360|Flex.