Adobe Flash Builder (flex4): addChild() is not available in this class.

Question

I want to load an swf into a flex 4 application in order to use its classes.

var ldr:Loader=new Loader();
ldr.load(new URLRequest("file://path/to/fileswf"));
ldr.contentLoaderInfo.addEventListener(Event.INIT, loaded);
function loaded(evt:Event):void { addChild(ldr); }

I receive the error:

Error: addChild() is not available in this class. Instead, use addElement() or modify the skin, if you have one.
at spark.components.supportClasses::SkinnableComponent/addChild()[E:\dev\gumbo_beta2\frameworks\projects\spark\src\spark\components\supportClasses\SkinnableComponent.as:966]
at main/private:init/loaded()[C:\Documents and Settings\ufk\Adobe Flash Builder Beta 2\xpogames-toolkit-test\src\main.mxml:22]

If I change addChild() to addElement(), I receive the following compilation error:

1067: Implicit coercion of a value of type flash.display:Loader to an unrelated type mx.core:IVisualElement. main.mxml path/dir line 22 Flex Problem

Any ideas how to resolve this issue?

Answer 1

Create another container to place the displayObject in:

// container ( IVisualElement ) for DisplayObjects
var container:UIComponent = new UIComponent();
addElement( container );

// displayObject goes to container
var displayO:Sprite = new Sprite();
container.addChild( displayO );