I have the following MXML:

<mx:Script>
    var someBoolean:Boolean = determineSomeCondition();
</mx:Script>

....

<foo:MyComponent somePropertyExpectingIDataRenderer="{
                                    someBoolean
                                    ? new Component1ThatImplementsIDataRenderer()
                                    : new Component2ThatImplementsIDataRenderer()
                                                     }">        
</foo:MyComponent>

I have also overridden the createChildren() function:

override protected function createChildren():void {
    super.createChildren();

    //do something with somePropertyExpectingIDataRenderer
}

My problem is: createChildren() is being called before the squiggly bracket logic is being evaluated, so in createChildren(), somePropertyExpectingIDataRenderer is null.

However if I pass the component via MXML like this:

<foo:MyComponent>
    <bar:somePropertyExpectingIDataRenderer>
        <baz:Component1ThatImplementsIDataRenderer/>
    </bar:somePropertyExpectingIDataRenderer>
</foo:MyComponent>

Then when createChildren() is called, that same property isn't null. Is this supposed to happen and if so, what other workarounds should I consider?