Cocos2D 2.1: “Delegate” deprecated in iOS 6. How do I set the delegate for this AVAudioSession?

Question

Started a Cocos2D 2.1 template (with no physics engine) in Xcode 4.5, targeted for iOS 6 and iPad. In the CDAudioManager.m file, the following code...

AVAudioSession* session = [AVAudioSession sharedInstance];
session.delegate = self;  // Which is what is automatically generated by the template.

...generates the following warning...

"delegate deprecated:  first deprecated in iOS 6"

So I go to the apple developer documentation, and it says under "delegate," "Deprecated in iOS 6.0. Use the notifications described in the Notifications section of this class instead."

http://developer.apple.com/library/ios/#documentation/AVFoundation/Reference/AVAudioSession_ClassReference/DeprecationAppendix/AppendixADeprecatedAPI.html#//apple_ref/occ/instp/AVAudioSession/delegate

Problem is, it looks to me like all we're trying to do--forgive my inexperience--is set the delegate for the AVAudioSession to the CDAudioManager instance itself. How do the notifications accomplish this? Or am I just wrong about the goal of the above code?

Answer 1

The error you are running into is in this block of code

AVAudioSession* session = [AVAudioSession sharedInstance];
session.delegate = self;// <-------- DEPRECATED IN IOS 6.0

To silence the warning change those 2 lines to this:

[[AVAudioSession sharedInstance] setActive:YES error:nil];

Hope this helps.

Answer 2

Instead of using delegate use notification for handling as follows

[AVAudioSession sharedInstance];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(interruption:) name:AVAudioSessionInterruptionNotification object:nil];

 - (void) interruption:(NSNotification*)notification
   {
    NSDictionary *interuptionDict = notification.userInfo;

    NSUInteger interuptionType = (NSUInteger)[interuptionDict valueForKey:AVAudioSessionInterruptionTypeKey];

   if (interuptionType == AVAudioSessionInterruptionTypeBegan)
        [self beginInterruption];

    else if (interuptionType == AVAudioSessionInterruptionTypeEnded)
        [self endInterruption];
}

Answer 3

I found a poast about this on the Cocos2D-iPhone.org forums. While I don't fully understand it--but I'm working on it--it did seem to take care of the problem, at least temporarily. What he did was write this method in the CDAudioManger.m file:

-(void) releaseBufferForFile:(NSString *) filePath {
    int bufferId = [self bufferForFile:filePath create:NO];
    if (bufferId != kCDNoBuffer) {
        [soundEngine unloadBuffer:bufferId];
        [loadedBuffers removeObjectForKey:filePath];
        NSNumber *freedBufferId = [[NSNumber alloc] initWithInt:bufferId];
        [freedBufferId autorelease];
        [freedBuffers addObject:freedBufferId];
    }
}
@end

- (void) interruption:(NSNotification*)notification
{
    NSDictionary *interuptionDict = notification.userInfo;
            NSNumber* interuptionTypeValue = [dict valueForKey:AVAudioSessionInterruptionTypeKey];
    NSUInteger interuptionType = [interuptionTypeValue intValue];

    if (interuptionType == AVAudioSessionInterruptionTypeBegan)
        [self beginInterruption];
#if __CC_PLATFORM_IOS >= 40000
    else if (interuptionType == AVAudioSessionInterruptionTypeEnded)
        [self endInterruptionWithFlags:(NSUInteger)[interuptionDict valueForKey:AVAudioSessionInterruptionOptionKey]];
#else
    else if (interuptionType == AVAudioSessionInterruptionTypeEnded)
        [self endInterruption];
#endif
}

Then he replaced:

AVAudioSession *session = [AVAudioSession sharedInstance];
session.delegate = self;

with this:

[AVAudioSession sharedInstance];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(interruption:) name:AVAudioSessionInterruptionNotification object:nil];

Here's the link: http://www.cocos2d-iphone.org/forum/topic/49956

If and when I develop a better understand of what this code is doing, I'll be sure to edit this post.

Answer 4

I haven't tested this but according to this post: http://www.cocos2d-iphone.org/forums/topic/cdaudiomanager-line-402-delegate-is-deprecated/#post-390211

float osVersion = [[UIDevice currentDevice].systemVersion floatValue];
if (osVersion >=6.0)
{
[AVAudioSession sharedInstance];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(interruption:) name:AVAudioSessionInterruptionNotification object:nil];
}
else
{
AVAudioSession* session = [AVAudioSession sharedInstance];
session.delegate = self;
}

I.e. throw different code runtime depending on iOS version.

Now, my app is iOS 6.0+ only anyway so I'll just go with:

[AVAudioSession sharedInstance];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(interruption:) name:AVAudioSessionInterruptionNotification object:nil];

And cross my thumbs.