playing a sound, waiting it to finish playing and continue (iphone) - iphone

Question

i'm new with the iphone and objective c, so far, I have been able to code some small examples.
i would like to play a sound and, continue with rest of the code when the sample finishes playing, i.e:
printf("hello");
playASound["file.wav"];
printf("world");
actually i'm getting: print hello, play the file and print world at the same time
but
what i want is: print hello, play the file, print world...
so, the question is how do i get it?
thanks
btw. here is the playASound code:
-(void) playASound: (NSString *) file {
//Get the filename of the sound file:
NSString *path = [NSString stringWithFormat:#"%#/%#",
[[NSBundle mainBundle] resourcePath],
file];
SystemSoundID soundID;
//Get a URL for the sound file
NSURL *filePath = [NSURL fileURLWithPath:path isDirectory:NO];
AudioServicesCreateSystemSoundID((CFURLRef)filePath, &soundID);
//play the file
AudioServicesPlaySystemSound(soundID);
}

Answer 1

From the documentation:
Discussion This function plays a short
sound (30 seconds or less in
duration). Because sound might play
for several seconds, this function is
executed asynchronously. To know when
a sound has finished playing, call the
AudioServicesAddSystemSoundCompletion
function to register a callback
function.
So you'll need to break up your function into two pieces: a function that calls PlayASound and prints "Hello", and a function that is called by the system when the sound is finished playing and prints "World".
// Change PlayASound to return the SystemSoundID it created
-(SystemSoundID) playASound: (NSString *) file {
//Get the filename of the sound file:
NSString *path = [NSString stringWithFormat:#"%#/%#",
[[NSBundle mainBundle] resourcePath],
file];
SystemSoundID soundID;
//Get a URL for the sound file
NSURL *filePath = [NSURL fileURLWithPath:path isDirectory:NO];
AudioServicesCreateSystemSoundID((CFURLRef)filePath, &soundID);
//play the file
AudioServicesPlaySystemSound(soundID);
return soundID;
}
-(void)startSound
{
printf("Hello");
SystemSoundID id = [self playASound:#"file.wav"];
AudioServicesAddSystemSoundCompletion (
id,
NULL,
NULL,
endSound,
NULL
);
}
void endSound (
SystemSoundID ssID,
void *clientData
)
{
printf("world\n");
}
See also docs for AudioServicesAddSystemSoundCompletion and AudioServicesSystemSoundCompletionProc.