Storing NSTimer objects in NSMutableDictionary

Question

Hi, using iphone sdk 4.o. I am attempting to store around 10 NSTimer object in a NSMutableDictionay and then index them by key. This is to save 10 diffent startTimer, stopTimer functions. I have done like this but am worried about memory leak issues

Is the below code safe, is it ok to copy timer objects into a dict. TimerList is a property of type NSMutableDictionary.

-(IBAction)startTimer:(NSNumber)identifier
{        
    NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:7
                       target:self selector:@selector(timerFireMethod:)
                       userInfo:nil  repeats:YES];    
    [self.TimerList setObject:timer forKey: identifier]; 
}


-(IBAction)stopTimer:(NSNumber)identifier
{        
    NSTimer* timer = [self.ReRegisterTimerList objectForKey: identifier];
    [timer invalidate];
    [self.TimerList setObject:nil forKey: identifier];  
}

-(void)timerFireMethod:(NSTimer*)theTimer
{    
    if (theTimer == [self.TimerList objectForKey:someKey])
    {
        found = true;
        // do something if its a certain timer                  
    }
}

Answer 1

Note that you take class-type instances by pointer, i.e. it should be NSNumber* not NSNumber.

Otherwise it looks fine to me - just remember the special consideration for -invalidate:

You must send this message from the thread on which the timer was installed.