iPhone: How to play a sound at a particular time?

I have written the following code:

-(void)runTimer
{
    myTicker=[NSTimer scheduledTimerWithTimeInterval:0.5 target:self selector:@selector(showActivity) userInfo:nil repeats开发者_开发百科:YES];
    myTicker = [NSTimer scheduledTimerWithTimeInterval:60.00 target:self selector:@selector(vibrate) userInfo:nil repeats:YES];
}

-(void)showActivity
{
    NSDateFormatter *formatter =
                  [[[NSDateFormatter alloc] init] autorelease];
            NSDate *date = [NSDate date];
        [formatter setTimeStyle:NSDateFormatterMediumStyle];
         [timerLabel setText:[formatter stringFromDate:date]];
}
-(void) vibrate{
AudioServicesPlaySystemSound (kSystemSoundID_Vibrate);

}

I want to play an audio file instead of vibrating the iPhone. Is that possible?

Tangential to the main question but the method called by the timer selector should be of the form...

-(void) aribtaryMethodName:(NSTimer *) theTimer;

...or it may not be called properly. It's selector should look like this:

myTicker=[NSTimer scheduledTimerWithTimeInterval:0.5 target:self selector:@selector(aribtaryMethodName:) userInfo:nil repeats:YES];

Check Apple's sample project BubbleLevel. You want the SoundEffect.h and SoundEffect.m into your project and then just call:

mySound = [[SoundEffect alloc]
    initWithContentsOfFile:[mainBundle pathForResource:@"mySound"
    ofType:@"aif"]];
[mySound play];    

Warning: I was able to play only AIF sounds converted via iTunes. Anything else failed, including CAF files. In short: import your whatever sound into iTunes (drag'n'drop), change export to AIF format and then export the file.

Yes. Assume you have a .caf file, you can play it with

SystemSoundID sound_id;
AudioServicesCreateSystemSoundID(NSURL_of_your_caf_file, &sound_id);
...
AudioServicesPlaySystemSound(sound_id);

To play music you may want to use AVAudioPlayer instead.

Sure. See AVAudioPlayer class.

-(IBAction)slider1Changed:(id)sender
{
    [timer invalidate];
    float sliderValue=slider1.value;
    int totalSecond=(int)sliderValue;
    time=totalSecond;
    int sec= totalSecond %60;
    int min= (totalSecond -sec)/60;
    sliderValue=(float)totalSecond;
    runTime.text=[NSString stringWithFormat:@"%d:%.2d",min,sec];
    [slider1 setValue:sliderValue];
    timer =   [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(timerChanged) userInfo:nil repeats:YES];

    // to play the audio from particular time duration
    [player setCurrentTime:totalSecond];
}

-(void)timerChanged
{
   int totalSecond=[player duration];

   float slider1Time=(float)time;
   if (time <= totalSecond) {
      int sec= time %60;
      int min= (time -sec)/60;
      runTime.text=[NSString stringWithFormat:@"%d:%.2d",min,sec];
      [slider1 setValue:slider1Time];
   }
   else
   {
      [player stop];
      [timer invalidate];
   }
   time +=1;

}