From: Albert Wagner <alwagner@...>
Date: 2002-07-07T08:37:32+09:00
Subject: Re: passing to objects at the bottom

On Saturday 06 July 2002 06:11 pm, Tom Sawyer wrote:
> i have a chain of objects such that one object contains another which
> contains another, and so on, down the line. the top object recieves a
> parameter which only the bottom most object in the chain is going to
> need. but how do i get it down there with out passing it through all the
> rest? and not using a global variable? for example:
>
<snip>
> how do i get a to Bottom without going through Middle, since Middle
> dosen't really need a. of course in my real program, i have about 4
> middles. does anyone have any better solutions to this problem?

I think the real answer would require more detail about what Top, Middle and  
Bottom are modeling.  Alan's answer would work for this example.  Also, 
refactoring so that Bottom is a subclass of Top that shares Top's accessors.  
It's hard to say without more info.