How to release MPMoviePlayerController?

Question

I have a couple of views that access the movie player. I've put the following code in a method in AppDelegate for these views. They send in the filename to play. The code works fine but I know a release is required somewhere. If I add the last line as a release or autorelease, the app will crash once the user presses done on the movieplayer.

MPMoviePlayerController *moviePlayer = [[MPMoviePlayerController alloc] 
                 initWithContentURL:[NSURL fileURLWithPath:moviePath]];
moviePlayer.movieControlMode = MPMovieControlModeDefault;
[moviePlayer play];
//[moviePlayer release];

I get this error:

objc[51051]: FREED(id): message videoViewController sent to freed object=0x1069b30

Program received signal: “EXC_BAD_INSTRUCTION”.

How should I be releasing the player?

Answer 1

What I've found is that the MPMoviePlayerController has to be sent the stop message before you can safely release it. So I do it in handlePlaybackEnd - first I stop it, then I autorelease it. Calling release doesn't seem to work too well:

- (void) moviePlayBackDidFinish : (NSNotification *) notification
{
  VideoPlayerController * player = notification.object;
  [player stop];
  [player autorelease];
}

The whole thing becomes a bit trickier in that the MPMoviePlayerPlaybackDidFinishNotification can get sent more than once, but calling stop/autorlease twice won't do you any good either. So you need to guard against that somehow.

Lastly, it seems to take a few iterations of the main run loop until you can safely create a new MPMoviePlayerController instance. If you do it too quickly, you'll get sound but no video. Great fun, huh?

Answer 2

To answer 4thSpace's comment on the answer above, you can remove the notification observer so you don't receive it multiple times:

- (void)moviePlayBackDidFinish:(NSNotification *)notification {
    MPMoviePlayerController *theMovie = [notification object];
    [[NSNotificationCenter defaultCenter] removeObserver:self
     name:MPMoviePlayerPlaybackDidFinishNotification
     object:theMovie];
    [theMovie stop];
    [theMovie release];
}

Answer 3

Stopping and releasing was not enough for me if the player did not reach to its end.

My solution is setting the "moviePlayer.initialPlaybackTime = -1 " at the "moviePlayBackDidFinish:" before releasing it:

-(void)playMovie: (NSString *)urlString{ movieURL = [NSURL URLWithString:urlString]; moviePlayer = [[MPMoviePlayerController alloc] initWithContentURL:movieURL]; moviePlayer.initialPlaybackTime = 0; [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(moviePlayBackDidFinish: ) name:MPMoviePlayerPlaybackDidFinishNotification object:moviePlayer] ;

moviePlayer.scalingMode = MPMovieScalingModeAspectFit; moviePlayer.movieControlMode = MPMovieControlModeDefault; moviePlayer.backgroundColor = [UIColor blackColor];

[moviePlayer play]; }

-(void)moviePlayBackDidFinish: (NSNotification*)notification{ [[NSNotificationCenter defaultCenter] removeObserver:self name:MPMoviePlayerPlaybackDidFinishNotification object:moviePlayer] ;

moviePlayer.initialPlaybackTime = -1;

[moviePlayer stop]; [moviePlayer release];

}

Answer 4

Hi all, I tried the above suggestions. still i can see a 16MB allocated , in INSTRUMENTS.... Is there anyone got a solution ?

UPDATE:

I found that the above suggestion will release the movieplayer instance. But the related cache is still maintained by framework ,w hich is around 16Mb in my app. I am playing a local movie file. Any suggestions ????

Answer 5

I had the same problem and I just realized I set the notification method with object:nil (it was a copy paste).

I was having multiple notifications although I shouldn't have had any notifications at all.

Here is my new notification set up code that fixed all (see the object:moviePlayer):

[[NSNotificationCenter defaultCenter] addObserver:self 
                           selector:@selector(moviePlaybackDidFinish:) 
                           name:MPMoviePlayerPlaybackDidFinishNotification 
                           object:moviePlayer]; 

Hope that helps. Now all my code is working properly.

Answer 6

for iphone os 3.2 you need to call [moviePlayer pause]; before calling [moviePlayer stop];

Answer 7

Wow thanks for the [moviePlayer pause]

Answer 8

moviePlayer.initialPlaybackTime = -1;

Thank You VM!

Answer 9

This seemed to reduce the memory significantly. However for IOS 4.1 it seems fine.

-(void) videoFinishedCallback:(NSNotification*)aNotification {

thePlayer = [aNotification object];
[[NSNotificationCenter defaultCenter]
 removeObserver:self
 name:MPMoviePlayerPlaybackDidFinishNotification
 object:thePlayer];

thePlayer.initialPlaybackTime = -1;

#if __IPHONE_OS_VERSION_MAX_ALLOWED >= 30200
    [thePlayer pause]; 
#endif

[thePlayer stop];
[thePlayer release];

}