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POissue with NSOperationQueue, weakSelf and blocks
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copied!<p>I have the following code:</p> <pre><code> [[AHPinterestAPIClient sharedClient] getPath:requestURLPath parameters:nil success:^(AFHTTPRequestOperation *operation, id response) { [weakSelf.backgroundQueue_ addOperationWithBlock:^{ [self doSomeHeavyComputation]; [[NSOperationQueue mainQueue] addOperationWithBlock:^{ [weakSelf.collectionView_ setContentOffset:CGPointMake(0, 0)]; [weakSelf.collectionView_ reloadData]; [weakSelf.progressHUD_ hide:YES]; [[NSNotificationCenter defaultCenter] performSelector:@selector(postNotificationName:object:) withObject:@"UIScrollViewDidStopScrolling" afterDelay:0.3]; [weakSelf.progressHUD_ hide:YES]; }]; }]; } failure:^(AFHTTPRequestOperation *operation, NSError *error) { [weakSelf.progressHUD_ hide:YES]; [weakSelf.collectionView_.pullToRefreshView stopAnimating]; NSLog(@"Error fetching user data!"); NSLog(@"%@", error); }]; </code></pre> <p>For some reason this worked just fine in iOS 5, but not iOS 6 (it crashes). Now I am not going to ask about iOS 6 because it's still under NDA. What I want to know is, whether the code above is wrong? If yes how do I fix it. </p> <p>If I put the code inside the block outside of the mainQueue then it's fine. What I am trying to do here is to do the NSOperationQueue mainQueue only after the [self doSomeHeavyComputation] is done. So this is a dependency, how should I add this dependency?</p> <p>Update:</p> <p>Here's the crash log if it helps:</p> <p><img src="https://i.stack.imgur.com/SHa3E.png" alt="enter image description here"></p>

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