Function calling

Why are the simplest things so obscure in actionscript…

I would like to know, how do you call a function that is inside another movieclip?

Do global functions have to be declared on the root?

I’m trying to do a very simple thing, take the grid tutorial and apply it as a mask to an image. Everything works ok, now I would like to call the function that makes the grid after the pic has loaded.

So I have on the root:
mc_picholder
mc_boxholder <—This mc contains the function that makes little boxes

I can assign the mc_boxholder as a mask to the mc_picholder and this works fine.

Now say I have a function in mc_boxholder called makeboxes(), and I want to call it from the root once a pic has finished loading into mc_picholder.

All the functions to make the boxes are inside the mc_boxholder. I’ve tried declaring makeboxes as global, and calling it from the root, doesn’t work.

I’ve tried tried writing from root: mx_boxholder.makeboxes(), doesn’t work either…

Would appreciate any help on how to handle these types of situations where you need to call functions on different movieclips from different locations.