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POXCODE - iOS Memory leak that is driving me crazy I think it's NSNotificationCenter, but hoping fresh eyes can see what I can't
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copied!<p>The code here is a modal view launched from the RootViewController and is to display a video with a thumbnail filmstrip below the movie and then timed instructions bound to the movie.</p> <p>It all works, but there is a memory leak / lack of release that I just can't see for looking and having spent three days trying to fix it, the time has come to ask for help...</p> <p>If I disable the NSNotificationCenter by commenting it out (highlighted in the .m) I don't have any issues regarding memory and keep the timed text. But I also don't have any thumbnails. I have tried inserting [[NSNotificationCenter alloc] removeObserver:self]; at numerous points to see if that will get rid of it for me. But alas, to no avail.</p> <p>I have also tried releasing the 'backgroundTimer' but it's not overly impressed when I try to compile and run.</p> <p>In essence, the first time I load the modal view, there are no issues whatsoever and all seems great - However, if I close it with the -(IBAction)close:(id)sender; it seems something isn't releasing as the next time I launch the same page the memory usage increases by about 30% (roughly the amount that is used by the thumbnail generation) and increases by roughly the same amount each time I re-launch the modal view.</p> <p>Please bare in mind I am a newbie to this and the error is likely to a bloody stupid one to those of you in the know. But in the interest of getting this project done, I'll gladly take any abuse you fancy throwing at me. </p> <p>Plus, it's my birthday tomorrow and if I can get this sorted, it would (rather sadly) be the best gift I could have!</p> <p>Here's the code........</p> <p>.h</p> <pre><code>#import <UIKit/UIKit.h> #import <MediaPlayer/MPMoviePlayerController.h> #import "ImageViewWithTime.h" #import "CommentView.h" @interface SirloinVideoViewController_iPad : UIViewController { UIView *landscapeView; UIView *viewForMovie; MPMoviePlayerController *player; UILabel *onScreenDisplayLabel; UIScrollView *myScrollView; NSMutableArray *keyframeTimes; NSArray *shoutOutTexts; NSArray *shoutOutTimes; NSTimer *backgroundTimer; UIView *instructions; } -(IBAction)close:(id)sender; -(IBAction)textInstructions:(id)sender; @property (nonatomic, retain) IBOutlet UIView *instructions; @property (nonatomic, retain) NSTimer *theTimer; @property (nonatomic, retain) NSTimer *backgroundTimer; @property (nonatomic, retain) IBOutlet UIView *viewForMovie; @property (nonatomic, retain) MPMoviePlayerController *player; @property (nonatomic, retain) IBOutlet UILabel *onScreenDisplayLabel; @property (nonatomic, retain) IBOutlet UIScrollView *myScrollView; @property (nonatomic, retain) NSMutableArray *keyframeTimes; -(NSURL *)movieURL; - (void) playerThumbnailImageRequestDidFinish:(NSNotification*)notification; - (ImageViewWithTime *)makeThumbnailImageViewFromImage:(UIImage *)image andTimeCode:(NSNumber *)timecode; - (void)handleTapFrom:(UITapGestureRecognizer *)recognizer; @end </code></pre> <p>.m</p> <pre><code>#import "SirloinVideoViewController_iPad.h" #import "SirloinTextViewController.h" @implementation SirloinVideoViewController_iPad @synthesize theTimer, backgroundTimer, viewForMovie, player, onScreenDisplayLabel, myScrollView, keyframeTimes, instructions; - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil { self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]; if (self) { } return self; [nibNameOrNil release]; [nibBundleOrNil release]; } - (IBAction)close:(id)sender{ [self.parentViewController dismissModalViewControllerAnimated:YES]; [player stop]; [player release]; [theTimer invalidate]; [theTimer release]; [backgroundTimer invalidate]; [SirloinVideoViewController_iPad release]; } </code></pre> <p>—</p> <pre><code>-(IBAction)textInstructions:(id)sender { SirloinTextViewController *vController = [[SirloinTextViewController alloc] initWithNibName:nil bundle:nil]; [self presentModalViewController:vController animated:YES]; [vController release]; } - (void)viewDidLoad { [super viewDidLoad]; keyframeTimes = [[NSMutableArray alloc] init]; shoutOutTexts = [[NSArray arrayWithObjects: @"1. XXXXXXXXXXXX", @"2. XXXXXXXXXXXX", @"3. XXXXXXXXXXXX", @"4. XXXXXXXXXXXX", @"5. XXXXXXXXXXXX", @"6. XXXXXXXXXXXX" @"7. XXXXXXXXXXXX", @"8. XXXXXXXXXXXX", @"9. XXXXXXXXXXXX", @"10. XXXXXXXXXXXX", @"11. XXXXXXXXXXXX", @"12. XXXXXXXXXXXX", @"13. XXXXXXXXXXXX", @"14. XXXXXXXXXXXX", @"15. XXXXXXXXXXXX", nil] retain]; shoutOutTimes = [[NSArray arrayWithObjects: [[NSNumber alloc] initWithInt: 1], [[NSNumber alloc] initWithInt: 73], [[NSNumber alloc] initWithInt: 109], [[NSNumber alloc] initWithInt: 131], [[NSNumber alloc] initWithInt: 205], [[NSNumber alloc] initWithInt: 250], [[NSNumber alloc] initWithInt: 337], [[NSNumber alloc] initWithInt: 378], [[NSNumber alloc] initWithInt: 402], [[NSNumber alloc] initWithInt: 420], [[NSNumber alloc] initWithInt: 448], [[NSNumber alloc] initWithInt: 507], [[NSNumber alloc] initWithInt: 531], [[NSNumber alloc] initWithInt: 574], nil] retain]; self.player = [[MPMoviePlayerController alloc] init]; self.player.contentURL = [self movieURL]; self.player.view.frame = self.viewForMovie.bounds; self.player.view.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight; [self.viewForMovie addSubview:player.view]; backgroundTimer = [NSTimer scheduledTimerWithTimeInterval:0.5f target:self selector:@selector(timerAction:) userInfo:nil repeats:YES]; [self.view addSubview:self.myScrollView]; //I am pretty sure that this is the culprit - Just not sure why... [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(movieDurationAvailable:) name:MPMovieDurationAvailableNotification object:theTimer]; //Could be wrong, but when commented out I don't have the memory issues } </code></pre> <p>—</p> <pre><code>- (NSInteger)positionFromPlaybackTime:(NSTimeInterval)playbackTime { NSInteger position = 0; for (NSNumber *startsAt in shoutOutTimes) { if (playbackTime > [startsAt floatValue]) { ++position; } } return position; } -(NSURL *)movieURL { NSBundle *bundle = [NSBundle mainBundle]; NSString *moviePath = [bundle pathForResource:@"sirloin" ofType:@"m4v"]; if (moviePath) { return [NSURL fileURLWithPath:moviePath]; } else { return nil; } } NSTimeInterval lastCheckAt = 0.0; </code></pre> <hr> <pre><code>- (void)timerAction: theTimer { int count = [shoutOutTimes count]; NSInteger position = [self positionFromPlaybackTime:self.player.currentPlaybackTime]; NSLog(@"position is at %d", position); if (position > 0) { --position; } if (position < count) { NSNumber *timeObj = [shoutOutTimes objectAtIndex:position]; int time = [timeObj intValue]; NSLog(@"shout scheduled for %d", time); NSLog(@"last check was at %g", lastCheckAt); NSLog(@"current playback time is %g", self.player.currentPlaybackTime); if (lastCheckAt < time && self.player.currentPlaybackTime >= time) { NSString *shoutString = [shoutOutTexts objectAtIndex:position]; NSLog(@"shouting: %@", shoutString); CommentView *cview = [[CommentView alloc] initWithText:shoutString]; [self.instructions addSubview:cview]; [shoutString release]; } } lastCheckAt = self.player.currentPlaybackTime; } </code></pre> <hr> <pre><code>// Override to allow orientations other than the default portrait orientation. - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { return YES; } -(void)removeObserver:(NSObject *)observer forKeyPath:(NSString *)keyPath { [[NSNotificationCenter defaultCenter] removeObserver:MPMovieDurationAvailableNotification]; [[NSNotificationCenter defaultCenter] removeObserver:MPMoviePlayerThumbnailImageRequestDidFinishNotification]; [keyPath release]; } - (void) movieDurationAvailable:(NSNotification*)notification { float duration = [self.player duration]; [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(playerThumbnailImageRequestDidFinish:) name:MPMoviePlayerThumbnailImageRequestDidFinishNotification object:nil]; NSMutableArray *times = [[NSMutableArray alloc] init]; for(int i = 0; i < 20; i++) { float playbackTime = i * duration/20; [times addObject:[NSNumber numberWithInt:playbackTime]]; } [self.player requestThumbnailImagesAtTimes:times timeOption: MPMovieTimeOptionExact]; } </code></pre> <hr> <pre><code>- (void) playerThumbnailImageRequestDidFinish:(NSNotification*)notification { NSDictionary *userInfo = [notification userInfo]; NSNumber *timecode = [userInfo objectForKey: MPMoviePlayerThumbnailTimeKey]; UIImage *image = [userInfo objectForKey: MPMoviePlayerThumbnailImageKey]; ImageViewWithTime *imageView = [self makeThumbnailImageViewFromImage:image andTimeCode:timecode]; [myScrollView addSubview:imageView]; UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleTapFrom:)]; [tapRecognizer setNumberOfTapsRequired:1]; [imageView addGestureRecognizer:tapRecognizer]; [tapRecognizer release]; [image release]; [imageView release]; } - (void)handleTapFrom:(UITapGestureRecognizer *)recognizer { ImageViewWithTime *imageView = (ImageViewWithTime *) recognizer.view; self.player.currentPlaybackTime = [imageView.time floatValue]; } </code></pre> <hr> <pre><code>- (ImageViewWithTime *)makeThumbnailImageViewFromImage:(UIImage *)image andTimeCode:(NSNumber *)timecode { float timeslice = self.player.duration / 3.0; int pos = [timecode intValue] / (int)timeslice; float width = 75 * ((float)image.size.width / (float)image.size.height); self.myScrollView.contentSize = CGSizeMake((width + 2) * 13, 75); ImageViewWithTime *imageView = [[ImageViewWithTime alloc] initWithImage:image]; [imageView setUserInteractionEnabled:YES]; [imageView setFrame:CGRectMake(pos * width + 2, 0, width, 75.0f)]; imageView.time = [[NSNumber alloc] initWithFloat:(pos * timeslice)]; return imageView; [myScrollView release]; } - (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; } - (void)dealloc { [player release]; [viewForMovie release]; [onScreenDisplayLabel release]; [keyframeTimes release]; [instructions release]; [shoutOutTexts release]; [shoutOutTimes release]; [super dealloc]; } @end </code></pre> <p>This app is already out there heavily using UIWebView (which just plain sux) so I am trying to things right and do it properly.... Thanks in advance!</p>

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