method "hasKey" of MapFx cannot be triggered by flex data binding mechanism about as3-commons HOT 26 OPEN

A two in one report.

1. Flex apparently looks at the declared type of the bindable reference for 
binding information. In your case IMap (second check box) does not provide any 
bindable properties and is therefore ignored. If you switch your initializer to 
"preinitialize", the check boxes are selected properly. But this is not what 
you want, is it?

2. You are right, the Fx collections do not have binding tags at all. You may 
catch change events with pure ActionScript approach (addEventListener). I will 
consider your feature request in the next bigger update.

Thanks for your reply. Yes, i just want to use the inner binding mechanism to 
get the view updated. I think add the Bindable metadata tag in IMap is a good 
idea no matter the instance is Map or MapFx. When I bind to IMap and 
instantiate a MapFx, I just think the data binding should work because I do not 
instantiate a Map.

[deleted comment]

A work-around for the problem is to create a sub-interface of IMap which is 
annotated with [Bindable], like:

    [Bindable]
    public interface IMapBindable extends IMap{


    }

In addition you need a subclass of Map that dispatches a PropertyChangeEvent 
whenever the map changes.

As long as you declare the variable of type IMapBindable the bindings will work.

https://github.com/AS3Commons/as3commons-collections/wiki/Roadmap-1.4

Hey Guys are you able to fork the project on GitHub, perform changes and submit 
a pull request?

Finished.
https://github.com/hydra1983/as3commons-collections
I just implemented everything including in my patch.

Where's the bindable-tag? 
https://github.com/hydra1983/as3commons-collections/blob/master/src/org/as3commo
ns/collections/framework/IMap.as

Here :-)

https://github.com/hydra1983/as3commons-collections/blob/master/src/org/as3commo
ns/collections/framework/IMapFx.as

You need on IMap as well, there's no sense in IMapFx being Bindable and IMap 
not. Also, the bindable-tag is to be placed on everything which value's might 
change due to the collectionChange-event.

You need to place it on itemFor as well.

Each of the collections comes in two versions: A plain and a bindable. The 
reason is simply performance. The majority of use cases utilize non-bindable 
versions.

Ah, that's fine. I still want the bindable-tag on itemFor though.

[deleted comment]

..since I want to do this:

<mx:Label text="{myMap.itemFor('foo')}"/>

And myMap is populated by some asynchronous call.

latest solutions:
#remove IMapFx and IDuplicatesFx

#set [Bindable("collectionChanged")] for IMap and MapFx methods:
* function hasKey(key : *) : Boolean;
* function itemFor(key : *) : *;
* function keysToArray() : Array;

#set [Bindable("collectionChanged")] for IDuplicates and MapFx methods:
function count(item : *) : uint;

I think Jens want the IMap-interface free of bindable-tags for performance. 
Looks like you guys got this under control, looking forward to the next release.

Is there actually any performance hit if no one is binding to those methods?  
Certainly the implementation that supports binding will be less performant as 
it is dispatching events on changes, but I don't see how Binding tag on IMap 
interface actually is affected.

If no one is binding to the methods, they don't need to be bindable in the 
first place.

If you're going to support data binding, Flex goes through all methods 
annotated with Bindable when the event is dispatched and look for clients.

See this article on data binding issues: 
http://www.screenshot.at/blog/2009/04/18/databinding-under-the-hood-part-1-perfo
rmance/

And google "dive into data binding waters" for another presentation on the 
implementation on data bindings.

@hydra do you mind to check the updated versions using this performance check 
tool?

http://code.google.com/p/sibirjak/source/browse/trunk/#trunk%2Fasperform%2Fcom%2
Fsibirjak%2Fasperform

It should be not more effort than just replace the as3commons collections 
version.

So, it's better to create a separate IMapxFx interface to support data binding 
and keep the unbindable IMap? 

By the way, I looked into 
com.sibirjak.asperform.collectiontests.CollectionTests, shoud I run all the 
tests? 

How can I know there is no performance problem with the updated version?

this is the performance test results. I run it with flash builder with sdk 3.5 
and have -debug set to false.

the results are from the execution of "AS3CommonsTests"