Overwriting Setters for Retain Properties

Is there any way to avoid this kind of code when overwriting the default setter for a retain property?

-(void)setMasterViewCon开发者_开发百科troller:(UIViewController *)newMaster {
    [newMaster retain];
    [masterViewController release];
    masterViewController = newMaster;

    // do custom stuff on set
}

Is there any way to access the default setter, something like:

-(void)setMasterViewController:(UIViewController *)newMaster {
    [defaultSetMasterViewController:newMaster];
    // do custom stuff
}

This would keep the code DRYer. The way I'm doing it currently, the fact that it's a retain property is mentioned twice.

CoreData generates primitive setters, but in general there's no such affordance. You may be able to replace custom setters with key-value observing in some cases, but the solution to your specific question is probably "use ARC" if you can limit support to 10.6+/4.3+. It will handle the retain/release stuff on your behalf.

Not really, because the setter has to perform the actual setting. You could try doing this using key-value observing if you want to keep the original setter.

However... Yes, if you're using ARC! If you have a @property (strong), then when you simply say masterViewController = newMaster ARC will use objc_storeStrong, which:

Performs the complete sequence for assigning to a __strong object of non-block type. Equivalent to the following code:

id objc_storeStrong(id *object, id value) {
  value = [value retain];
  id oldValue = *object;
  *object = value;
  [oldValue release];
  return value;
}