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copied!<p>I think you should heed the static analyser message in this case. Your pattern has potential problems.</p> <p>Specifically, when you return from the method invoked to do step 5, you are in a method of an object that may already have been deallocated. I interpret your pattern something like this:</p> <pre><code>// steps 1, 2, 3 -(void) methodThatCreatesObject { id theObj = [[TheObj alloc] init]; [theObj setDelegate: delegateObj]; // other stuff } </code></pre> <p>Note the above breaches the <a href="http://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/MemoryMgmt/Articles/mmRules.html" rel="nofollow">memory management rules</a></p> <pre><code>// step 4 - a method of theObj -(void) someMethod { [delegate notifyTaskCompleteFromObj: self]; // self points to an invalid object here. Doing anything with self results in EXC_BAD_ACCESS } </code></pre> <p>The above breaches an assumption stated in the memory management rules:</p> <blockquote> <p>A received object is normally guaranteed to remain valid within the method it was received in</p> </blockquote> <p>if we say <code>self</code> is a received object, which it is technically, since it is passed as a parameter on the stack.</p> <pre><code>// step 5 the delegate method defined in the delegate object -(void) notifyTaskCompleteFromObj: (TheObj*) anObj { // do stuff [anObj release]; } </code></pre> <p>The above also breaches the memory management rules.</p> <p>The normal pattern is to have a controller that owns both the delegate and the object that has the delegate (often the controller is itself the delegate). I think you should move to that pattern.</p>

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