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POHow to release a viewController and his view inside of an NSMutableArray viewControllers?
 

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  1. POHow to release a viewController and his view inside of an NSMutableArray viewControllers?
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    <p>I have a big problem with my memory management. A actually have a big magazine and every page it is render with his own PageViewController. My code it's totally based on PageControl sample of Apple Documentation, if you guys have seen sometime.</p> <p>So, in the viewDidLoad of my "MainViewController" I create a NSMutableArray = self.viewControllers full of NSNull objects. And I call my <code>[self loadScrollViewPage:page];</code> for my first and second pages. When the user navigate into more pages, I call (from scrollViewDidScroll) more load <code>[self loadScrollViewPage:nextPage];</code> as the App will be need it. Also I implement a <code>unloadScrollViewPage:page</code> 'cause the magazine is so big, that the memory will be out if I don't.</p> <p>So, this is my code:</p> <pre><code>- (void)loadScrollViewPage:(int)pageNumber { if ((pageNumber &lt; 0) || (pageNumber &gt;= [self.viewControllers count])) return; PageViewController *controller = [self.viewControllers objectAtIndex:pageNumber]; if ((NSNull *)controller == [NSNull null]) { controller = [[PageViewController alloc] initWithPage:[self.pages objectAtIndex:pageNumber]]; [self.viewControllers replaceObjectAtIndex:pageNumber withObject:controller]; [controller release]; } if (controller.view.superview == nil) { CGRect frame = mainpageScrollView.frame; frame.origin.x = 0; frame.origin.y = frame.size.height * pageNumber; controller.view.frame = frame; [mainpageScrollView addSubview:controller.view]; } } - (void)unloadScrollViewPage:(int)pageNumber { if ((pageNumber &lt; 0) || (pageNumber &gt;= [self.viewControllers count])) return; if ((NSNull *)[self.viewControllers objectAtIndex:pageNumber] != [NSNull null]) { [[[self.viewControllers objectAtIndex:pageNumber] view] removeFromSuperview]; [self.viewControllers removeObjectAtIndex:pageNumber]; [self.viewControllers replaceObjectAtIndex:pageNumber withObject:[NSNull null]]; } } </code></pre> <p>The problem is, no matter how many times I call <code>unloadScrollViewPage</code>, the memory still increment size when I call <code>loadScrollViewPage</code> and never decrement with <code>unloadScrollViewPage</code>. So, when the user is going in the 10 page (of 300 pages, lol?) the memory size of my App is of 100Mb and of course, it crash :(</p> <p>My questions are:</p> <ul> <li>Am I releasing memory correctly from my self.viewControllers NSMutableArray?</li> <li>The views of each controller that I put on they superview (the view of MainViewController) will release it when I removeObjectAtIndex:pageNumber from the self.viewControllers? If not, how can I do it? Is this my problem?</li> </ul> <p>Thanks in advanced.</p> <p><strong>EDIT:</strong></p> <p>Looks like <strong>Firoze Lafeer</strong> was right at the beginning, the problem was my UIImage memory management and my views retained. I just manage to removeFromSuperview each UIView. For the images, looks like using <code>[UIImage imageNamed]</code> it implements a cache (that release it when ios wants ¬¬). I just change the way using <code>[UIImage imageWithData:imageData];</code> which doesn't implements cache and all my objects are happy now. Thanks everybody. :)</p>
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