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    <p><code>updateResult</code> is an instance variable which prevents the object from being deallocated as it is retained by that block. </p> <p>In other words, you got a retain cycle. The object retains the block and the block retains the object.</p> <p>You will need to create a weak or unsafe_unretained reference to that instance and its variable for loosing that relationship.</p> <p>Add the following prior to your notification block:</p> <pre><code>__unsafe_unretained YouObjectClass *weakSelf = self; </code></pre> <p>or (in case you are on iOS5 and above)</p> <pre><code>__weak YouObjectClass *weakSelf = self; </code></pre> <p>Then, within that block, reference the object via that new weak reference:</p> <pre><code>[[NSNotificationCenter defaultCenter] addObserverForName:@"Update result"                                                   object:nil                                                    queue:nil                                               usingBlock:^(NSNotification *note) {                                                   weakSelf.updateResult = YES;                                               }]; </code></pre> <p>Please note that retain-cycles are not a bad thing per se. Sometimes you actually want them to happen. But those are instances where you are certain that the cycle will be broken after a specific time (e.g. Animation Blocks). The cycle is broken once the block has executed and is removed from the stack.</p>
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    1. COI have other blocks that call on methods like `[self updateType:@"someType"];` that have the same problem. Is a retain cycle also happening here? Also, can you be more specific on how to "create a weak or unsafe_unretained reference to that instance and its variable"? I'm still relatively new at this... Thanks!
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    2. COYes, that will also create a retain cycle. Sometimes such cycles are entirely fine - but only in cases where the block is guaranteed to execute. The retain-cycle will be broken once the block has finished its execution (e.g. animation blocks).
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    3. COThanks for being very helpful and clear. :)
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