Retain/release of instance variables

[miket]

I have created a class which has instance variables that are other classes that I generated, so I have:

class1.h:

@interface class1 : NSObject {
   class2 *var2;
}

@property (nonatomic, retain) class2 *var2;

When I allocate and then release a class1 variable, it creates but then does not release var2 and I get a memory leak. However, if I use an NSString instance variable rather than a class2 instance variable, I don't get a memory leak...

Is this how Objective C is supposed to work? Is there some way I can make my class2 behave in a similar manner to NSString?

(I've got rid of the leak by adding [var2 release] to the class1 release method, and [var2 retain] to the class1 retain method... but I feel like I'm missing something else...??)

Thanks for any insight
Mike

[chicagosky]

I'm very new to this myself but it might have something to do with the "retain" clause you have in the property declaration. When an instance variable is created, the retain count is automatically incremented to 1, but the fact that you have retain in the property declaration could increment it by one more. A simple way to check could be by logging the retain count on this property in the dealloc method of your class.

[smasher]

You should add a [var2 release] in the dealloc method for your class. That will balance the retain from the property. If it's still leaking then post the code where you set var2.

Don't look at NSString to see how your classes will behave. NSStrings, especially static strings like @"this" do not always work like other classes. You should retain/release them just like any other class, but something different is going on under the hood.

[miket]

Thanks. I found that explicitly adding "release" on my variables seemed to clear it up. I was curious why it hadn't happened in my other cases. The comments here confirm my suspicions!

Thanks for the tips!

Mike