title: Can Custom Setters Break KVO Pattern? Break Retain or Copy Pattern?
body: <p>In Objective-C, I wonder whether a custom setter will override the KVO support (willChangeValueForKey: and didChangeValueForKey;) and do I need to include calls to these explicitly in the custom setter?</p>
  
  <p>What about Retain and Copy? Would I need to explcitly include release and retain or copy in the setter for properties with Retain or Copy attributes (for non-ARC code)?</p>