Problem
Accessing a child component in an Accordion view throws a null object reference error.
Solution
Access the components only after they are instantiated or change the creationPolicy property of the Accordion to all.
Detailed explanation
Child components creation is by default deferred in case of multiple view containers like Accordion, TabNavigator and ViewStack i.e. Accordion only creates direct descendants and waits for the user to access the views to create components in various views. This is done for better performance, which is a good thing because you don’t want all the child components to be created unless the user uses them right.
If you don’t want to wait till the user access the components and just want to access them, you can either change the creationPolicy property of the Accordion to all.
Note: Changing the creationPolicy to all is not recommended.
Please find more details at this URL http://livedocs.adobe.com/flex/3/html/layoutperformance_05.html
