Singleton Class ArrayCollection within Flashbuilder (Mobile) empty?

Question

Hi,
I am currently trying to implememnt a Singleton Class in order to store a ArrayCollection of items that I can then access and manipulate across the lifecycle of my app. I have created the below Singleton Class that is designed to hold the ArrayCollection information:
package valueObjects
    import mx.collections.ArrayCollection;   
    [Bindable]
    public class Model
        private static var instance:Model = new Model();
        public var ids:ArrayCollection = new ArrayCollection();
        public function Model()
            if(instance)
                trace("New instance cannot be created. Use Singleton.getInstance()");
        public static function getInstance():Model
            return instance;
I have then created the following code on the Main Deafult page for my application so that the ArrayCollection is populated as soon as the app is initiated:
            import valueObjects.Model;           
            protected var models:Model = new Model();
                        private function loop():void
                var index:int;
                for( index = 0; index < compsCollection.length; index++ )
                    trace( "Element " + index + " is " +  compsCollection[index].comp_id );
                                models.ids.addItem(compsCollection[index].comp_id);
                    trace(models.ids.length);
The ArrayCollection in the Singleton Class is being populated as the trace statement that I have entered into the loop clearly shows the build of of data in the ArrayCollection. However then when I move to another view within the application I then try to access this ArrayCollection within the Singleton Class with the following code:
import valueObjects.Model;
protected var models:Model = Model.getInstance();
protected var test:ArrayCollection = new ArrayCollection();
protected function view1_viewActivateHandler(event:ViewNavigatorEvent):void
                var index:int;
                trace("Array Length =" + models.ids.length);
                for( index = 0; index < models.ids.length; index++ )
                    trace( "Element " + index + " is " + models.ids[index].comp_id );
                    test.addItem(models.ids[index].comp_id);
                testbox.text = test.toString();
Now the problem I am having is that when I try to access this ArrayCollection(ids) it appears to be empty for some reason. I have included a trace statement that also says that the length of the ArrayCollection is "0". Can anyone please help??

Answer 1

if your value object class change this
change this
public var ids:ArrayCollection = new ArrayCollection();
to
public static var ids:ArrayCollection = new ArrayCollection();
on your default page change this
models.ids.addItem(compsCollection[index].comp_id);
to
valueObjects.Model.ids.addItem(compsCollection[index].comp_id);
on your view change to something like this.
protected
function view1_viewActivateHandler():void
               //initialize="view1_viewActivateHandler();"
               var index:int;
               trace("Array Length =" + valueObjects.Model.ids.length);
               for( index = 0; index < valueObjects.Model.ids.length; index++ )
                    trace( "Element " + index + " is " + valueObjects.Model.ids[index].comp_id );
                    test.addItem(valueObjects.Model.ids[index].comp_id);
               //testbox.text = test.toString();
good luck let me know if you have any question i tested this and it worked like a charm for me.
Miguel