Re: Multiple Inheritance
Re: Multiple Inheritance
- Subject: Re: Multiple Inheritance
- From: Lance Bland <email@hidden>
- Date: Tue, 1 Jan 2002 14:16:56 -0500
On Tuesday, January 1, 2002, at 01:11 PM, Gerriet M. Denkmann wrote:
I have two classes: MyCell and MyButtonCell. (Subclassed in the obvious
way).
Obvious? I assume you mean NSCell -> MyCell and NSButtonCell ->
MyButtonCell.
And there are several methods which are identical for both classes.
One - not very elegant - way would be to copy & paste the code for the
identical methods.
But surely there is a better way ?
You can:
1) Add a Category to NSCell with those methods defined in that category.
(Doesn't work if the methods need additional ivars).
2) Add a delegate ivar to both MyCell and MyButtonCell and make that
ivar an instance of a class that implements your common methods and
forward calls to the delegate.
3) Put the method definitions in a separate file and then place an
#include precompiler directive to include that file (and hence those
methods) into your classes at compile time. (don't use #import)
4) Write a program to duplicate the methods for any desired class (that
is what we ended up doing).
-lance
_______________________________________________
Lance Bland
System Administrator at VVI
mailto:email@hidden
http://www.vvi.com
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