Move child movie clip from one parent object to another

Question

Hi everyone,
I am somewhat new to AS3, and I'm having a hard time working out the most appropriate way to move a child movieclip between parent objects.
I'm creating a board-game type game wherein I've dynamically created an array of 'Square' movieclips, with no visual elements, which are arranged in a 10x10 rectangle on the stage. I then dynamically add the appropriate types of piece movieclips to the various squares with the addChild() method. In general, a square should only have one child piece at a time.
All of this works well for setting up the play area, but now I'm having an issue with moving a piece from one square to another. I want to have the user click a square with a piece on it, then click the destination square to move the piece. I have the logic for determining where a user can move any given piece to, but I don't know how to actually move the piece.
The pieces are all different class objects that extend both a base class I call Piece as well as the MovieClip class. The main issue is that when dynamically adding the various pieces to the squares, I don't provide them a unique name to access them later. I don't bother with unique names because I have no way of knowing which piece instance will be in a given square, so using getChildByName(name:String) isn't very useful.
So I can think of two routes that I can take: Making a getter/setter for the Square class that manages a private Piece property (as well as the adding and removing of the child piece to/from the parent square), or using getChildAt(index:int) to try to access the child piece.
I want to go with the first route as it seems to be the most maintainable to me. My problem is that I can't work out how to manage empty squares in this scenario. My instinct is to null to private _piece property of one square once I've moved the child piece instance to another square... but I'm fairly certain that the private property is a reference type, and nulling it out will null the actual piece object even after it's changed parents.
I'm sorry for the long description. I'm hoping that my lack of experience with as3 it what's causing my trouble, and that someone more well versed will know of the best way to handle this. Maybe I'm overthinking everything.
If something isn't clear, please feel free to ask me for clarification. I would appeciate any help that anyone may be able to offer.
Thanks!
- Scott

Answer 1

for a square with a child, you can use:
whateversquare.getChildAt(0);  // to reference whateversquare's only child.  although, if there are graphics in whateversquare, you may need to use getChildAt(1)
or, if you want to use a square class getter/setter, what's the problem?  an empty square will return null.