Accessing objects on stage

programming flash
1

Hello all,

Could someone explain me the concept of objects at the stage? How I would access them.

For example: I’ve made 3 classes, in one of them I made an container that contains a Circle. In another class I want to access them. So I know the structure of the stage is now as follow:

stage
_ container
____ circle

First I thought about giving the container a name so I could access it with getChildByName(). Only when I try stage.getChildByName() I get the error that I cannot access a property or method of a null object reference.

Thanks in advance